allow build once more
[oweals/gnunet.git] / src / transport / plugin_transport_wlan.c
index f184ff47aeaa217fcc09dbe5d03762066c5f0d89..51c6d3053d8cd499715711c44d3f2a519651bd4f 100644 (file)
 #include "plugin_transport_wlan.h"
 #include "gnunet_common.h"
 #include "gnunet_crypto_lib.h"
+#include "gnunet_fragmentation_lib.h"
+//#include "wlan/ieee80211.h"
+//#include  <netinet/ip.h>
+
+#include <string.h>
 
 #define PROTOCOL_PREFIX "wlan"
 
 /**
  * Max size of packet from helper
  */
-#define WLAN_MTU 3000
+#define WLAN_MTU 1450
 
 /**
  * Time until retransmission of a fragment in ms
  */
 #define FRAGMENT_TIMEOUT GNUNET_TIME_UNIT_SECONDS
 
+/**
+ * max size of fragment queue
+ */
 #define FRAGMENT_QUEUE_SIZE 10
+/**
+ * max messages in fragment queue per session/client
+ */
+#define FRAGMENT_QUEUE_MESSAGES_OUT_PER_SESSION 1
+
+/**
+ * max messages in fragment queue per MAC
+ */
+#define FRAGMENT_QUEUE_MESSAGES_OUT_PER_MACENDPOINT 1
 
+/**
+ * time until message in in queue
+ */
+#define MESSAGE_IN_TIMEOUT GNUNET_TIME_UNIT_SECONDS
+
+/**
+ * max messages in in queue
+ */
+#define MESSAGES_IN_QUEUE_SIZE 10
+/**
+ * max messages in in queue per session/client
+ */
+#define MESSAGES_IN_DEFRAG_QUEUE_PER_MAC 1
+/**
+ * scaling factor for hello beacon
+ */
 #define HALLO_BEACON_SCALING_FACTOR 900
 
 #define DEBUG_wlan GNUNET_NO
+#define DEBUG_wlan_retransmission GNUNET_NO
+#define DEBUG_wlan_ip_udp_packets_on_air GNUNET_NO
 
 #define MESSAGE_LENGHT_UNKNOWN -1
-#define NO_MESSAGE_OR_MESSAGE_FINISHED -2
-
+//#define NO_MESSAGE_OR_MESSAGE_FINISHED -2
+/**
+ * size of log for recently used incomming messages id
+ */
+#define MESSAGE_ID_BACKLOG_SIZE 5
 /**
  * After how long do we expire an address that we
  * learned from another peer if it is not reconfirmed
  */
 #define LEARNED_ADDRESS_EXPIRATION GNUNET_TIME_relative_multiply (GNUNET_TIME_UNIT_HOURS, 6)
 
+#define IEEE80211_ADDR_LEN      6               /* size of 802.11 address */
+
+#define IEEE80211_FC0_VERSION_MASK              0x03
+#define IEEE80211_FC0_VERSION_SHIFT             0
+#define IEEE80211_FC0_VERSION_0                 0x00
+#define IEEE80211_FC0_TYPE_MASK                 0x0c
+#define IEEE80211_FC0_TYPE_SHIFT                2
+#define IEEE80211_FC0_TYPE_MGT                  0x00
+#define IEEE80211_FC0_TYPE_CTL                  0x04
+#define IEEE80211_FC0_TYPE_DATA                 0x08
+
+/*
+ * Structure of an internet header, naked of options.
+ */
+struct iph
+{
+#if __BYTE_ORDER == __LITTLE_ENDIAN
+  unsigned int ip_hl :4; /* header length */
+  unsigned int ip_v :4; /* version */
+#endif
+#if __BYTE_ORDER == __BIG_ENDIAN
+  unsigned int ip_v:4; /* version */
+  unsigned int ip_hl:4; /* header length */
+#endif
+  u_int8_t ip_tos; /* type of service */
+  u_short ip_len; /* total length */
+  u_short ip_id; /* identification */
+  u_short ip_off; /* fragment offset field */
+#define IP_RF 0x8000                    /* reserved fragment flag */
+#define IP_DF 0x4000                    /* dont fragment flag */
+#define IP_MF 0x2000                    /* more fragments flag */
+#define IP_OFFMASK 0x1fff               /* mask for fragmenting bits */
+  u_int8_t ip_ttl; /* time to live */
+  u_int8_t ip_p; /* protocol */
+  u_short ip_sum; /* checksum */
+  struct in_addr ip_src, ip_dst; /* source and dest address */
+};
+
+struct udphdr
+{
+  u_int16_t source;
+  u_int16_t dest;
+  u_int16_t len;
+  u_int16_t check;
+};
+
+/*
+ * generic definitions for IEEE 802.11 frames
+ */
+struct ieee80211_frame
+{
+  u_int8_t i_fc[2];
+  u_int8_t i_dur[2];
+  u_int8_t i_addr1[IEEE80211_ADDR_LEN];
+  u_int8_t i_addr2[IEEE80211_ADDR_LEN];
+  u_int8_t i_addr3[IEEE80211_ADDR_LEN];
+  u_int8_t i_seq[2];
+#if DEBUG_wlan_ip_udp_packets_on_air
+u_int8_t llc[4];
+struct iph ip;
+struct udphdr udp;
+#endif
+}GNUNET_PACKED;
 /**
  * Initial handshake message for a session.
  */
@@ -91,31 +192,28 @@ struct Plugin
   struct GNUNET_TRANSPORT_PluginEnvironment *env;
 
   /**
-   * List of open sessions. head
+   * List of open connections. head
    */
-  struct Sessionqueue *sessions;
+  struct MacEndpoint * mac_head;
 
   /**
-   * List of open sessions. tail
+   * List of open connections. tail
    */
-  struct Sessionqueue *sessions_tail;
+  struct MacEndpoint * mac_tail;
 
   /**
-   * Number of sessions
+   * Number of connections
    */
-
-  int session_count;
+  unsigned int mac_count;
 
   /**
    * encapsulation of data from the local wlan helper program
    */
-
   struct GNUNET_SERVER_MessageStreamTokenizer * suid_tokenizer;
 
   /**
-   * encapsulation of packets received
+   * encapsulation of packets received from the wlan helper
    */
-
   struct GNUNET_SERVER_MessageStreamTokenizer * data_tokenizer;
 
   /**
@@ -170,13 +268,13 @@ struct Plugin
 
   /**
    * Sessions currently pending for transmission
-   * to this peer, if any.
+   * to a peer, if any.
    */
-  struct Sessionqueue * pending_Sessions;
+  struct Sessionqueue * pending_Sessions_head;
 
   /**
    * Sessions currently pending for transmission
-   * to this peer (tail), if any.
+   * to a peer (tail), if any.
    */
   struct Sessionqueue * pending_Sessions_tail;
 
@@ -186,39 +284,42 @@ struct Plugin
   unsigned int pendingsessions;
 
   /**
-   * Messages in the fragmentation queue, head
+   * Messages in the sending queues
    */
-
-  struct FragmentMessage * pending_Fragment_Messages_head;
+  int pending_Fragment_Messages;
 
   /**
-   * Messages in the fragmentation queue, tail
+   * messages ready for send, head
    */
-
-  struct FragmentMessage * pending_Fragment_Messages_tail;
-
+  struct FragmentMessage_queue * sending_messages_head;
   /**
-   * number of pending fragment message
+   * messages ready for send, tail
    */
-
-  unsigned int pending_fragment_messages;
-
+  struct FragmentMessage_queue * sending_messages_tail;
   /**
    * time of the next "hello-beacon"
    */
-
   struct GNUNET_TIME_Absolute beacon_time;
 
   /**
-   * queue to send acks for received fragments
+   * queue to send acks for received fragments (head)
    */
-
   struct AckSendQueue * ack_send_queue_head;
 
+  /**
+   * queue to send acks for received fragments (tail)
+   */
   struct AckSendQueue * ack_send_queue_tail;
 
+  /**
+   * Tracker for bandwidth limit
+   */
+  struct GNUNET_BANDWIDTH_Tracker tracker;
 };
 
+/**
+ * Struct to store data if file write did not accept the whole packet
+ */
 struct Finish_send
 {
   struct Plugin * plugin;
@@ -230,7 +331,7 @@ struct Finish_send
 /**
  * Queue of sessions, for the general session queue and the pending session queue
  */
-
+//TODO DOXIGEN
 struct Sessionqueue
 {
   struct Sessionqueue * next;
@@ -239,27 +340,43 @@ struct Sessionqueue
 };
 
 /**
- * Queue of ack received for messages send
+ * Queue of fragmented messages, for the sending queue of the plugin
  */
-
-struct AckQueue
+//TODO DOXIGEN
+struct FragmentMessage_queue
 {
-  struct AckQueue * next;
-  struct AckQueue * prev;
-  int fragment_num; //TODO change it to offset if better
+  struct FragmentMessage_queue * next;
+  struct FragmentMessage_queue * prev;
+  struct FragmentMessage * content;
 };
 
 /**
  * Queue for the fragments received
  */
-
-struct RecQueue
+//TODO DOXIGEN
+struct Receive_Fragment_Queue
 {
-  struct RecQueue * next;
-  struct RecQueue * prev;
+  struct Receive_Fragment_Queue * next;
+  struct Receive_Fragment_Queue * prev;
   uint16_t num;
   const char * msg;
   uint16_t size;
+  struct Radiotap_rx rxinfo;
+};
+
+//TODO DOXIGEN
+struct MacEndpoint_id_fragment_triple
+{
+  struct MacEndpoint * endpoint;
+  uint32_t message_id;
+  struct FragmentMessage * fm;
+};
+
+//TODO DOXIGEN
+struct Plugin_Session_pair
+{
+  struct Plugin * plugin;
+  struct Session * session;
 };
 
 /**
@@ -268,11 +385,19 @@ struct RecQueue
  */
 struct PendingMessage
 {
+  /**
+   * dll next
+   */
+  struct PendingMessage * next;
+  /**
+   * dll prev
+   */
+  struct PendingMessage * prev;
 
   /**
    * The pending message
    */
-  char *msg;
+  struct WlanHeader *msg;
 
   /**
    * Size of the message
@@ -301,24 +426,38 @@ struct PendingMessage
 /**
  * Queue for acks to send for fragments recived
  */
-//TODO comments
 struct AckSendQueue
 {
 
+  /**
+   * next ack in the ack send queue
+   */
   struct AckSendQueue * next;
+  /**
+   * previous ack in the ack send queue
+   */
   struct AckSendQueue * prev;
-
-  struct Session * session;
+  /**
+   * pointer to the session this ack belongs to
+   */
+  struct MacEndpoint * endpoint;
   /**
    * ID of message, to distinguish between the messages, picked randomly.
    */
-  uint32_t message_id GNUNET_PACKED;
+  uint32_t message_id;
 
   /**
-   * Offset or number of this fragment, for fragmentation/segmentation (design choice, TBD)
+   * msg to send
    */
-  uint16_t fragment_off_or_num GNUNET_PACKED;
-
+  struct GNUNET_MessageHeader * hdr;
+  /**
+   * pointer to the ieee wlan header
+   */
+  struct ieee80211_frame * ieeewlanheader;
+  /**
+   * pointer to the radiotap header
+   */
+  struct Radiotap_Send * radioHeader;
 };
 
 /**
@@ -334,7 +473,12 @@ struct Session_light
   /**
    * peer mac address
    */
-  uint8_t addr[6];
+  struct MacAddress addr;
+
+  /**
+   * mac endpoint
+   */
+  struct MacEndpoint * macendpoint;
 };
 
 /**
@@ -349,15 +493,16 @@ struct Session
   struct SessionHeader header;
 
   /**
-   * Pointer to the global plugin struct.
+   * Message currently pending for transmission
+   * to this peer, if any. head
    */
-  struct Plugin *plugin;
+  struct PendingMessage * pending_message_head;
 
   /**
    * Message currently pending for transmission
-   * to this peer, if any.
+   * to this peer, if any. tail
    */
-  struct PendingMessage *pending_message;
+  struct PendingMessage * pending_message_tail;
 
   /**
    * To whom are we talking to (set to our identity
@@ -365,42 +510,6 @@ struct Session
    */
   struct GNUNET_PeerIdentity target;
 
-  /**
-   * encapsulation of the receive data
-   */
-  //struct GNUNET_SERVER_MessageStreamTokenizer * receive_token;
-
-  /**
-   * offset of the next fragment for the receive_token, -1 means last message finished
-   */
-
-  //int rec_offset;
-
-  /**
-   * size of the message received,
-   * MESSAGE_LENGHT_UNKNOWN means that the size is not known,
-   * NO_MESSAGE_OR_MESSAGE_FINISHED means no message received
-   */
-
-  int rec_size;
-
-  /**
-   * Sorted queue with the fragments received; head
-   */
-
-  struct RecQueue * frag_head;
-
-  /**
-   * Sorted queue with the fragments received; tail
-   */
-
-  struct RecQueue * frag_tail;
-
-  /**
-   * peer mac address
-   */
-  char addr[6];
-
   /**
    * Address of the other peer (either based on our 'connect'
    * call or on our 'accept' call).
@@ -414,379 +523,387 @@ struct Session
   struct GNUNET_TIME_Absolute last_activity;
 
   /**
-   * current number for message incoming, to distinguish between the messages
-   */
-  uint32_t message_id_in;
-
-  /**
-   * current number for message outgoing, to distinguish between the messages
+   * peer connection
    */
-  uint32_t message_id_out;
+  struct MacEndpoint * mac;
 
   /**
-   * does this session have a message in the fragment queue
+   * count of messages in the fragment out queue for this session
    */
 
-  int has_fragment;
+  int fragment_messages_out_count;
 
 };
 
 /**
- * Struct for Messages in the fragment queue
+ * Struct to represent one network card connection
  */
-
-struct FragmentMessage
+struct MacEndpoint
 {
   /**
-   * Session this message belongs to
+   * Pointer to the global plugin struct.
    */
-
-  struct Session *session;
-
+  struct Plugin *plugin;
   /**
-   * This is a doubly-linked list.
+   * Struct to hold the session reachable over this mac; head
    */
-  struct FragmentMessage *next;
-
+  struct Sessionqueue * sessions_head;
   /**
-   * This is a doubly-linked list.
+   * Struct to hold the session reachable over this mac; tail
    */
-  struct FragmentMessage *prev;
-
+  struct Sessionqueue * sessions_tail;
   /**
-   * The pending message
+   * Messages currently sending
+   * to a peer, if any.
    */
-  char *msg;
+  struct FragmentMessage * sending_messages_head;
 
   /**
-   * Timeout value for the pending message.
+   * Messages currently sending
+   * to a peer (tail), if any.
    */
-  struct GNUNET_TIME_Absolute timeout;
-
+  struct FragmentMessage * sending_messages_tail;
   /**
-   * Timeout value for the pending fragments.
-   * Stores the time when the next msg fragment ack has to be received
+   * dll next
    */
-  struct GNUNET_TIME_Absolute next_ack;
-
+  struct MacEndpoint *next;
   /**
-   * Sorted queue with the acks received for fragments; head
+   * dll prev
    */
-
-  struct AckQueue * head;
+  struct MacEndpoint *prev;
 
   /**
-   * Sorted queue with the acks received for fragments; tail
+   * peer mac address
    */
-
-  struct AckQueue * tail;
+  struct MacAddress addr;
 
   /**
-   * Size of the message
+   * Defrag context for this mac endpoint
    */
-  size_t message_size;
+  struct GNUNET_DEFRAGMENT_Context * defrag;
 
   /**
-   * pos / next fragment number in the message, for fragmentation/segmentation,
-   * some acks can be missing but there is still time
+   * count of messages in the fragment out queue for this mac endpoint
    */
-  uint32_t message_pos;
-
-};
 
-/**
- * Header for messages which need fragmentation
- */
-struct WlanHeader
-{
+  int fragment_messages_out_count;
 
-  struct GNUNET_MessageHeader header;
+  //TODO DOXIGEN
+  uint8_t rate;
+  uint16_t tx_power;
+  uint8_t antenna;
 
   /**
-   * checksum/error correction
+   * Duplicates received
    */
-  uint32_t crc GNUNET_PACKED;
+  int dups;
 
   /**
-   * To whom are we talking to (set to our identity
-   * if we are still waiting for the welcome message)
+   * Fragments received
    */
-  struct GNUNET_PeerIdentity target;
-
-// followed by payload
+  int fragc;
 
+  /**
+   * Acks received
+   */
+  int acks;
 };
 
 /**
- * Header for messages which need fragmentation
+ * Struct for Messages in the fragment queue
  */
-struct FragmentationHeader
-{
 
-  struct GNUNET_MessageHeader header;
+struct FragmentMessage
+{
 
   /**
-   * To whom are we talking to (set to our identity
-   * if we are still waiting for the welcome message)
+   * Session this message belongs to
    */
-  // struct GNUNET_PeerIdentity target GNUNET_PACKED;
+
+  struct Session *session;
 
   /**
-   * ID of message, to distinguish between the messages, picked randomly.
+   * This is a doubly-linked list.
    */
-  uint32_t message_id GNUNET_PACKED;
+  struct FragmentMessage *next;
 
   /**
-   * Offset or number of this fragment, for fragmentation/segmentation (design choice, TBD)
+   * This is a doubly-linked list.
    */
-  uint16_t fragment_off_or_num GNUNET_PACKED;
+  struct FragmentMessage *prev;
 
   /**
-   * CRC of fragment (for error checking)
+   * Timeout value for the pending message.
    */
-  uint16_t message_crc GNUNET_PACKED;
+  struct GNUNET_TIME_Absolute timeout;
 
-/**
- * Flags
- * // 0x1 ack => Use two different message types in header.type! (FRAG_MESSAGE; FRAG_ACK)
- * // 0x2 has data (not only ack)
- * // 0x4 last fragment of message
- * // 0x8 new message
- */
-//  uint32_t flags GNUNET_PACKED;
+  /**
+   * Fragmentation context
+   */
+  struct GNUNET_FRAGMENT_Context * fragcontext;
 
-/**
- * checksum/error correction
- */
-// uint32_t crc GNUNET_PACKED;
+  /**
+   * Fragment to send
  */
+  char * frag;
 
-// followed by payload unless ACK
+  /**
+   * size of message
+   */
+  size_t size;
 
+  /**
+   * pointer to the ieee wlan header
+   */
+  struct ieee80211_frame * ieeewlanheader;
+  /**
+   * pointer to the radiotap header
+   */
+  struct Radiotap_Send * radioHeader;
 };
 
-int
-getRadiotapHeader(struct RadiotapHeader * Header);
-
-int
-getWlanHeader(struct IeeeHeader * Header,const char * to_mac_addr,
-    struct Plugin * plugin);
-
-static int
-wlan_plugin_address_suggested(void *cls, const void *addr, size_t addrlen);
-
-uint16_t
-getcrc16(const char *msgbuf, size_t msgbuf_size);
-
 static void
 do_transmit(void *cls, const struct GNUNET_SCHEDULER_TaskContext *tc);
-
-static void
-check_fragment_queue(struct Plugin * plugin);
-
-uint32_t
-getcrc32(const char *msgbuf, size_t msgbuf_size);
-
 static void
-free_rec_frag_queue(struct Session * session);
+free_session(struct Plugin * plugin, struct Sessionqueue * queue,
+    int do_free_macendpoint);
+static struct MacEndpoint *
+create_macendpoint(struct Plugin *plugin, const struct MacAddress *addr);
 
-static void
-wlan_data_helper(void *cls, struct Session_light * session_light,
-    const struct GNUNET_MessageHeader * hdr);
+/**
+ * Generates a nice hexdump of a memory area.
+ *
+ * \param  mem     pointer to memory to dump
+ * \param  length  how many bytes to dump
+ */
+void
+hexdump(void *mem, unsigned length)
+{
+  char line[80];
+  char *src = (char*) mem;
 
-static void
-wlan_process_helper(void *cls, void *client,
-    const struct GNUNET_MessageHeader *hdr);
+  printf(
+      "dumping %u bytes from %p\r\n"
+        "       0  1  2  3  4  5  6  7  8  9  A  B  C  D  E  F    0123456789ABCDEF\r\n",
+      length, src);
+  unsigned i;
+  int j;
 
-static void
-finish_sending(void *cls, const struct GNUNET_SCHEDULER_TaskContext *tc);
+  for (i = 0; i < length; i += 16, src += 16)
+    {
+      char *t = line;
 
-static void
-wlan_data_massage_handler(struct Plugin * plugin,
-    struct Session_light * session_light,
-    const struct GNUNET_MessageHeader * hdr);
+      t += sprintf(t, "%04x:  ", i);
+      for (j = 0; j < 16; j++)
+        {
+          if (i + j < length)
+            t += sprintf(t, "%02X", src[j] & 0xff);
+          else
+            t += sprintf(t, "  ");
+          t += sprintf(t, j % 2 ? " " : "-");
+        }
 
-static const char *
-wlan_plugin_address_to_string(void *cls, const void *addr, size_t addrlen);
+      t += sprintf(t, "  ");
+      for (j = 0; j < 16; j++)
+        {
+          if (i + j < length)
+            {
+              if (isprint((unsigned char)src[j]))
+                t += sprintf(t, "%c", src[j]);
+              else
+                t += sprintf(t, ".");
+            }
+          else
+            {
+              t += sprintf(t, " ");
+            }
+        }
 
-/**
- * get the next message number, at the moment just a random one
- * @return returns the next valid message-number for sending packets
- */
-uint32_t
-get_next_message_id()
-{
-  return GNUNET_CRYPTO_random_u32(GNUNET_CRYPTO_QUALITY_NONCE, UINT32_MAX);
+      t += sprintf(t, "\r\n");
+      printf("%s", line);
+    }
 }
 
 /**
- * start next message number generator
- * (not necessary at the moment)
+ * Function to find a MacEndpoint with a specific mac addr
+ * @param plugin pointer to the plugin struct
+ * @param addr pointer to the mac address
+ * @param create_new GNUNET_YES if a new end point should be created
+ * @return
  */
-void
-start_next_message_id()
+static struct MacEndpoint *
+get_macendpoint(struct Plugin *plugin, const struct MacAddress *addr,
+    int create_new)
 {
-  //GNUNET_CRYPTO_random_init;
-}
+  struct MacEndpoint * queue = plugin->mac_head;
+  while (queue != NULL)
+    {
+      GNUNET_assert (queue->sessions_head != NULL);
+      if (memcmp(addr, &queue->addr, sizeof(struct MacAddress)) == 0)
+        return queue; /* session found */
+      queue = queue->next;
+    }
+
+  if (create_new == GNUNET_YES)
+    {
+      return create_macendpoint(plugin, addr);
+    }
+  else
+    {
+      return NULL;
+    }
 
+}
 /**
- * search for a session with the addr
+ * search for a session with the addr and peer id
  *
  * @param plugin pointer to the plugin struct
  * @param addr pointer to the mac address of the peer
+ * @param peer pointer to the peerid
  * @return returns the session
  */
-
 static struct Session *
-search_session(struct Plugin *plugin, const uint8_t * addr)
+search_session(struct Plugin *plugin, const struct MacEndpoint * endpoint,
+    const struct GNUNET_PeerIdentity * peer)
 {
-  struct Sessionqueue * queue = plugin->sessions;
-  struct Sessionqueue * lastitem = NULL;
+  GNUNET_assert(endpoint != NULL);
+  struct Sessionqueue * queue = endpoint->sessions_head;
 
-  //just look at all the session for the needed one
   while (queue != NULL)
     {
-      // content is never NULL
       GNUNET_assert (queue->content != NULL);
-      char * addr2 = queue->content->addr;
-      if (memcmp(addr, addr2, 6) == 0)
-        {
-          //sesion found
-          return queue->content;
-        }
-      // try next
-      lastitem = queue;
+      if (memcmp(peer, &queue->content->target,
+          sizeof(struct GNUNET_PeerIdentity)) == 0)
+        return queue->content; /* session found */
       queue = queue->next;
     }
   return NULL;
 }
 
 /**
- * create a new session
+ * Function called for a quick conversion of the binary address to
+ * a numeric address.  Note that the caller must not free the
+ * address and that the next call to this function is allowed
+ * to override the address again.
  *
- * @param plugin pointer to the plugin struct
- * @param addr pointer to the mac address of the peer
- * @return returns the session
+ * @param cls closure
+ * @param addr binary address
+ * @param addrlen length of the address
+ * @return string representing the same address
  */
-
-static struct Session *
-create_session(struct Plugin *plugin, const uint8_t * addr)
+static const char*
+wlan_plugin_address_to_string(void *cls, const void *addr, size_t addrlen)
 {
-  struct Sessionqueue * queue = GNUNET_malloc (sizeof (struct Sessionqueue));
-
-  GNUNET_CONTAINER_DLL_insert_tail(plugin->sessions, plugin->sessions_tail, queue);
+  static char ret[40];
+  const struct MacAddress *mac;
 
-  queue->content = GNUNET_malloc (sizeof (struct Session));
-  queue->content->plugin = plugin;
-  memcpy(queue->content->addr, addr, 6);
-  queue->content->message_id_out = get_next_message_id();
-  queue->content->has_fragment = 0;
-  queue->content->rec_size = NO_MESSAGE_OR_MESSAGE_FINISHED;
+  if (addrlen != sizeof(struct MacAddress))
+    {
+      GNUNET_break (0);
+      return NULL;
+    }
+  mac = addr;
+  GNUNET_snprintf(ret, sizeof(ret), "%s Mac-Address %X:%X:%X:%X:%X:%X",
+      PROTOCOL_PREFIX, mac->mac[0], mac->mac[1], mac->mac[2], mac->mac[3],
+      mac->mac[4], mac->mac[5]);
+  return ret;
+}
+
+/**
+ * create a new session
+ *
+ * @param plugin pointer to the plugin struct
+ * @param addr pointer to the mac endpoint of the peer
+ * @return returns the session
+ */
+
+static struct Session *
+create_session(struct Plugin *plugin, struct MacEndpoint * endpoint,
+    const struct GNUNET_PeerIdentity * peer)
+{
+  GNUNET_assert(endpoint != NULL);
+  struct Sessionqueue * queue = GNUNET_malloc (sizeof (struct Sessionqueue));
 
-  plugin->session_count++;
+  GNUNET_CONTAINER_DLL_insert_tail(endpoint->sessions_head, endpoint->sessions_tail, queue);
+
+  queue->content = GNUNET_malloc (sizeof (struct Session));
+  queue->content->mac = endpoint;
+  memcpy(&(queue->content->target), peer, sizeof(struct GNUNET_PeerIdentity));
 
 #if DEBUG_wlan
-      GNUNET_log(GNUNET_ERROR_TYPE_DEBUG,
-          "New session %p with %s\n", queue->content ,wlan_plugin_address_to_string(NULL,addr, 6));
+  GNUNET_log(GNUNET_ERROR_TYPE_DEBUG, "New session %p with endpoint %p: %s\n",
+      queue->content, endpoint,
+      wlan_plugin_address_to_string(NULL, endpoint->addr.mac, 6));
 #endif
 
   return queue->content;
 }
 
 /**
- * get Session from address, create if no session exists
+ * Get session from address, create if no session exists
  *
  * @param plugin pointer to the plugin struct
  * @param addr pointer to the mac address of the peer
+ * @param peer pointer to the peerid
  * @return returns the session
  */
-//TODO add other possibilities to find the right session (are there other?)
 static struct Session *
-get_Session(struct Plugin *plugin, const uint8_t * addr)
+get_session(struct Plugin *plugin, const struct MacAddress *addr,
+    const struct GNUNET_PeerIdentity * peer)
 {
-  struct Session * session = search_session(plugin, addr);
+  struct MacEndpoint * mac;
+  mac = get_macendpoint(plugin, addr, GNUNET_YES);
+  struct Session * session = search_session(plugin, mac, peer);
+
   if (session != NULL)
-    {
-      return session;
-    }
-  // new session
-  return create_session(plugin, addr);
-
-  /* -- not needed, layer above already has it--
-   //queue welcome message for new sessions, not realy needed
-   //struct WelcomeMessage welcome;
-   struct PendingMessage *pm;
-   pm = GNUNET_malloc (sizeof (struct PendingMessage));
-   pm->msg = GNUNET_malloc(GNUNET_HELLO_size(* (plugin->env->our_hello)));
-   pm->message_size = GNUNET_HELLO_size(* (plugin->env->our_hello));
-   //welcome.header.size = htons (GNUNET_HELLO_size(* (plugin->env->our_hello)));
-   //welcome.header.type = htons (GNUNET_MESSAGE_TYPE_WLAN_ADVERTISEMENT);
-   //welcome.clientIdentity = *plugin->env->my_identity;
-   memcpy ( (pm->msg), * plugin->env->our_hello, GNUNET_HELLO_size(* (plugin->env->our_hello)));
-   pm->timeout = GNUNET_TIME_UNIT_FOREVER_ABS;
-   queue->content->pending_message = pm;
-   plugin->pendingsessions ++;
-   GNUNET_CONTAINER_DLL_insert_tail(plugin->pending_Sessions, plugin->pending_Sessions_tail, queue);
-
-   check_fragment_queue(plugin);
-   */
+    return session;
+  return create_session(plugin, mac, peer);
 }
 
 /**
  * Queue the session to send data
+ * checks if there is a message pending
+ * checks if this session is not allready in the queue
+ * @param plugin pointer to the plugin
+ * @param session pointer to the session to add
  */
-//TODO doxigen
 static void
-queue_Session(struct Plugin *plugin, struct Session * session)
+queue_session(struct Plugin *plugin, struct Session * session)
 {
-  struct Sessionqueue * queue = plugin->pending_Sessions;
-  struct Sessionqueue * lastitem = NULL;
+  struct Sessionqueue * queue = plugin->pending_Sessions_head;
 
-  while (queue != NULL)
+  if (session->pending_message_head != NULL)
     {
-      // content is never NULL
-      GNUNET_assert (queue->content != NULL);
-      // is session already in queue?
-      if (session == queue->content)
+      while (queue != NULL)
         {
-          return;
+          // content is never NULL
+          GNUNET_assert (queue->content != NULL);
+          // is session already in queue?
+          if (session == queue->content)
+            {
+              return;
+            }
+          // try next
+          queue = queue->next;
         }
-      // try next
-      lastitem = queue;
-      queue = queue->next;
-    }
-
-  // Session is not in the queue
 
-  queue = GNUNET_malloc (sizeof (struct Sessionqueue));
-  queue->content = session;
+      // Session is not in the queue
 
-  //insert at the tail
-  GNUNET_CONTAINER_DLL_insert_after (plugin->pending_Sessions,
-      plugin->pending_Sessions_tail,
-      plugin->pending_Sessions_tail, queue);
-  plugin->pendingsessions++;
-
-}
+      queue = GNUNET_malloc (sizeof (struct Sessionqueue));
+      queue->content = session;
 
-//TODO doxigen
-static void
-free_acks(struct FragmentMessage * fm)
-{
-  struct AckQueue * fq;
-  while (fm->head != NULL)
-    {
-      fq = fm->head;
-      GNUNET_CONTAINER_DLL_remove(fm->head, fm->tail, fq);
-      GNUNET_free(fq);
+      //insert at the tail
+      GNUNET_CONTAINER_DLL_insert_tail(plugin->pending_Sessions_head,
+          plugin->pending_Sessions_tail, queue);
+      plugin->pendingsessions++;
     }
-  //needed?
-  fm->head = NULL;
-  fm->tail = NULL;
+
 }
 
-//TODO doxigen
 /**
  * Function to schedule the write task, executed after a delay
+ * @param cls pointer to the plugin struct
+ * @param tc GNUNET_SCHEDULER_TaskContext pointer
  */
 static void
 delay_fragment_task(void *cls, const struct GNUNET_SCHEDULER_TaskContext *tc)
@@ -794,7 +911,7 @@ delay_fragment_task(void *cls, const struct GNUNET_SCHEDULER_TaskContext *tc)
   struct Plugin * plugin = cls;
   plugin->server_write_delay_task = GNUNET_SCHEDULER_NO_TASK;
 
-  if (tc->reason == GNUNET_SCHEDULER_REASON_SHUTDOWN)
+  if (0 != (tc->reason & GNUNET_SCHEDULER_REASON_SHUTDOWN))
     return;
 
   // GNUNET_TIME_UNIT_FOREVER_REL is needed to clean up old msg
@@ -806,118 +923,142 @@ delay_fragment_task(void *cls, const struct GNUNET_SCHEDULER_TaskContext *tc)
     }
 }
 
-//TODO doxigen
 /**
  * Function to calculate the time of the next periodic "hello-beacon"
+ * @param plugin pointer to the plugin struct
  */
+
 static void
 set_next_beacon_time(struct Plugin * const plugin)
 {
   //under 10 known peers: once a second
-  if (plugin->session_count < 10)
+  if (plugin->mac_count < 10)
     {
       plugin->beacon_time = GNUNET_TIME_absolute_add(
-          GNUNET_TIME_absolute_get(), GNUNET_TIME_relative_multiply(
-              GNUNET_TIME_UNIT_SECONDS, HALLO_BEACON_SCALING_FACTOR));
+          GNUNET_TIME_absolute_get(),
+          GNUNET_TIME_relative_multiply(GNUNET_TIME_UNIT_SECONDS,
+              HALLO_BEACON_SCALING_FACTOR));
     }
   //under 30 known peers: every 10 seconds
-  else if (plugin->session_count < 30)
+  else if (plugin->mac_count < 30)
     {
       plugin->beacon_time = GNUNET_TIME_absolute_add(
-          GNUNET_TIME_absolute_get(), GNUNET_TIME_relative_multiply(
-              GNUNET_TIME_UNIT_SECONDS, 10 * HALLO_BEACON_SCALING_FACTOR));
+          GNUNET_TIME_absolute_get(),
+          GNUNET_TIME_relative_multiply(GNUNET_TIME_UNIT_SECONDS,
+              10 * HALLO_BEACON_SCALING_FACTOR));
     }
   //over 30 known peers: once a minute
   else
     {
       plugin->beacon_time = GNUNET_TIME_absolute_add(
-          GNUNET_TIME_absolute_get(), GNUNET_TIME_relative_multiply(
-              GNUNET_TIME_UNIT_MINUTES, HALLO_BEACON_SCALING_FACTOR));
+          GNUNET_TIME_absolute_get(),
+          GNUNET_TIME_relative_multiply(GNUNET_TIME_UNIT_MINUTES,
+              HALLO_BEACON_SCALING_FACTOR));
     }
 }
 
-//TODO doxigen
-struct GNUNET_TIME_Relative
-get_next_frag_timeout(struct FragmentMessage * fm)
-{
-  return GNUNET_TIME_relative_min(GNUNET_TIME_absolute_get_remaining(
-      fm->next_ack), GNUNET_TIME_absolute_get_remaining(fm->timeout));
-}
-
-//TODO doxigen
-/**
- * Function to get the timeout value for acks for this session
- */
-
-struct GNUNET_TIME_Relative
-get_ack_timeout(struct FragmentMessage * fm)
-{
-  return FRAGMENT_TIMEOUT;
-}
-
 /**
  * Function to set the timer for the next timeout of the fragment queue
  * @param plugin the handle to the plugin struct
  */
+
 static void
-check_next_fragment_timeout(struct Plugin * const plugin)
+set_next_send(struct Plugin * const plugin)
 {
-  struct FragmentMessage * fm;
   struct GNUNET_TIME_Relative next_send;
 
-  next_send = GNUNET_TIME_absolute_get_remaining(plugin->beacon_time);
-
   //cancel old task
   if (plugin->server_write_delay_task != GNUNET_SCHEDULER_NO_TASK)
     {
       GNUNET_SCHEDULER_cancel(plugin->server_write_delay_task);
       plugin->server_write_delay_task = GNUNET_SCHEDULER_NO_TASK;
     }
-  fm = plugin->pending_Fragment_Messages_head;
-
-  GNUNET_assert(plugin->server_write_delay_task == GNUNET_SCHEDULER_NO_TASK);
 
   //check if some acks are in the queue
   if (plugin->ack_send_queue_head != NULL)
     {
-      next_send = GNUNET_TIME_relative_get_zero();
+      next_send = GNUNET_TIME_UNIT_ZERO;
     }
+
   //check if there are some fragments in the queue
-  else if (fm != NULL)
+  else if (plugin->sending_messages_head != NULL)
+    {
+      next_send = GNUNET_TIME_UNIT_ZERO;
+    }
+  else
+    {
+      next_send = GNUNET_TIME_absolute_get_remaining(plugin->beacon_time);
+    }
+
+#if DEBUG_wlan
+
+  GNUNET_log(GNUNET_ERROR_TYPE_DEBUG, "Next packet is send in: %u\n",
+      next_send.rel_value);
+
+#endif
+
+  if (next_send.rel_value == GNUNET_TIME_UNIT_ZERO.rel_value)
+    {
+      if (plugin->server_write_task == GNUNET_SCHEDULER_NO_TASK)
+        {
+          plugin->server_write_task = GNUNET_SCHEDULER_add_write_file(
+              GNUNET_TIME_UNIT_FOREVER_REL, plugin->server_stdin_handle,
+              &do_transmit, plugin);
+        }
+    }
+  else
     {
-      next_send
-          = GNUNET_TIME_relative_min(next_send, get_next_frag_timeout(fm));
+      if (plugin->server_write_delay_task == GNUNET_SCHEDULER_NO_TASK)
+        {
+          plugin->server_write_delay_task = GNUNET_SCHEDULER_add_delayed(
+              next_send, &delay_fragment_task, plugin);
+        }
     }
-  plugin->server_write_delay_task = GNUNET_SCHEDULER_add_delayed(next_send,
-      &delay_fragment_task, plugin);
 }
 
-//TODO doxigen
 /**
  * Function to get the next queued Session, removes the session from the queue
+ * @param plugin pointer to the plugin struct
+ * @return pointer to the session found, returns NULL if there is now session in the queue
  */
-
 static struct Session *
-get_next_queue_Session(struct Plugin * plugin)
+get_next_queue_session(struct Plugin * plugin)
 {
   struct Session * session;
   struct Sessionqueue * sessionqueue;
   struct Sessionqueue * sessionqueue_alt;
   struct PendingMessage * pm;
-  sessionqueue = plugin->pending_Sessions;
+  sessionqueue = plugin->pending_Sessions_head;
+
   while (sessionqueue != NULL)
     {
       session = sessionqueue->content;
-      pm = session->pending_message;
+
+      GNUNET_assert(session != NULL);
+      pm = session->pending_message_head;
+
+#if DEBUG_wlan
+      if (pm == NULL)
+        {
+          GNUNET_log(GNUNET_ERROR_TYPE_ERROR,
+              "pending message is empty, should not happen. session %p\n",
+              session);
+        }
+#endif
+
+      GNUNET_assert(pm != NULL);
 
       //check for message timeout
       if (GNUNET_TIME_absolute_get_remaining(pm->timeout).rel_value > 0)
         {
           //check if session has no message in the fragment queue
-          if (!session->has_fragment)
+          if ((session->mac->fragment_messages_out_count
+              < FRAGMENT_QUEUE_MESSAGES_OUT_PER_MACENDPOINT)
+              && (session->fragment_messages_out_count
+                  < FRAGMENT_QUEUE_MESSAGES_OUT_PER_SESSION))
             {
               plugin->pendingsessions--;
-              GNUNET_CONTAINER_DLL_remove (plugin->pending_Sessions,
+              GNUNET_CONTAINER_DLL_remove (plugin->pending_Sessions_head,
                   plugin->pending_Sessions_tail, sessionqueue);
               GNUNET_free(sessionqueue);
 
@@ -930,8 +1071,8 @@ get_next_queue_Session(struct Plugin * plugin)
         }
       else
         {
+          GNUNET_CONTAINER_DLL_remove(session->pending_message_head, session->pending_message_tail, pm);
 
-          session->pending_message = NULL;
           //call the cont func that it did not work
           if (pm->transmit_cont != NULL)
             pm->transmit_cont(pm->transmit_cont_cls, &(session->target),
@@ -939,50 +1080,22 @@ get_next_queue_Session(struct Plugin * plugin)
           GNUNET_free(pm->msg);
           GNUNET_free(pm);
 
-          sessionqueue_alt = sessionqueue;
-          sessionqueue = sessionqueue->next;
-          plugin->pendingsessions--;
-          GNUNET_CONTAINER_DLL_remove (plugin->pending_Sessions,
-              plugin->pending_Sessions_tail, sessionqueue_alt);
-
-          GNUNET_free(sessionqueue_alt);
+          if (session->pending_message_head == NULL)
+            {
+              sessionqueue_alt = sessionqueue;
+              sessionqueue = sessionqueue->next;
+              plugin->pendingsessions--;
+              GNUNET_CONTAINER_DLL_remove (plugin->pending_Sessions_head,
+                  plugin->pending_Sessions_tail, sessionqueue_alt);
 
+              GNUNET_free(sessionqueue_alt);
+            }
         }
 
     }
   return NULL;
 }
 
-/**
- * Function to sort the message into the message fragment queue
- * @param plugin the plugin struct
- * @param fm message to sort into the queue
- */
-static void
-sort_fragment_into_queue(struct Plugin * plugin, struct FragmentMessage * fm)
-{
-  struct FragmentMessage * fm2;
-  //sort into the list at the right position
-
-  fm2 = plugin->pending_Fragment_Messages_head;
-
-  while (fm2 != NULL)
-    {
-      if (GNUNET_TIME_absolute_get_difference(fm2->next_ack, fm->next_ack).rel_value
-          == 0)
-        {
-          break;
-        }
-      else
-        {
-          fm2 = fm2->next;
-        }
-    }
-
-  GNUNET_CONTAINER_DLL_insert_after(plugin->pending_Fragment_Messages_head,
-      plugin->pending_Fragment_Messages_tail,fm2,fm);
-}
-
 /**
  * frees the space of a message in the fragment queue (send queue)
  * @param plugin the plugin struct
@@ -991,171 +1104,212 @@ sort_fragment_into_queue(struct Plugin * plugin, struct FragmentMessage * fm)
 static void
 free_fragment_message(struct Plugin * plugin, struct FragmentMessage * fm)
 {
+  struct Session * session = fm->session;
+  struct MacEndpoint * endpoint = session->mac;
+  struct FragmentMessage_queue * fmq;
+  struct FragmentMessage_queue * fmq_next;
+
   if (fm != NULL)
     {
-      free_acks(fm);
-      GNUNET_free_non_null(fm->msg);
-      GNUNET_CONTAINER_DLL_remove (plugin->pending_Fragment_Messages_head,
-          plugin->pending_Fragment_Messages_tail, fm);
+      fmq = plugin->sending_messages_head;
+      while (fmq != NULL)
+        {
+          fmq_next = fmq->next;
+          if (fmq->content == fm)
+            {
+              GNUNET_CONTAINER_DLL_remove(plugin->sending_messages_head,plugin->sending_messages_tail, fmq);
+              GNUNET_free(fmq);
+            }
+          fmq = fmq_next;
+        }
+
+      (session->mac->fragment_messages_out_count)--;
+      session->fragment_messages_out_count--;
+      plugin->pending_Fragment_Messages--;
+      GNUNET_CONTAINER_DLL_remove(endpoint->sending_messages_head,endpoint->sending_messages_tail, fm);
+      GNUNET_FRAGMENT_context_destroy(fm->fragcontext);
       GNUNET_free(fm);
-      plugin->pending_fragment_messages--;
-      check_fragment_queue(plugin);
 
+      queue_session(plugin, session);
 #if DEBUG_wlan
-          GNUNET_log(GNUNET_ERROR_TYPE_DEBUG, "Pending fragment messages: %u\n", plugin->pending_fragment_messages);
+      GNUNET_log(GNUNET_ERROR_TYPE_DEBUG,
+          "Free pending fragment messages %p, session %p\n", fm, session);
 #endif
     }
 }
 
 /**
- * Function to check if there is some space in the fragment queue
- * inserts a message if space is available
- * @param plugin the plugin struct
+ * function to fill the radiotap header
+ * @param plugin pointer to the plugin struct
+ * @param endpoint pointer to the endpoint
+ * @param header pointer to the radiotap header
+ * @return GNUNET_YES at success
  */
-
-static void
-check_fragment_queue(struct Plugin * plugin)
+static int
+getRadiotapHeader(struct Plugin * plugin, struct MacEndpoint * endpoint,
+    struct Radiotap_Send * header)
 {
-  struct Session * session;
-  struct FragmentMessage * fm;
-  struct GNUNET_PeerIdentity pid;
 
-  struct PendingMessage * pm;
-
-  if (plugin->pending_fragment_messages < FRAGMENT_QUEUE_SIZE)
+  if (endpoint != NULL)
     {
-      session = get_next_queue_Session(plugin);
-      if (session != NULL)
-        {
-          pm = session->pending_message;
-          session->pending_message = NULL;
-          session->has_fragment = 1;
-          GNUNET_assert(pm != NULL);
-
-          fm = GNUNET_malloc(sizeof(struct FragmentMessage));
-          fm->message_size = pm->message_size;
-          fm->msg = pm->msg;
-          fm->session = session;
-          fm->timeout.abs_value = pm->timeout.abs_value;
-          fm->message_pos = 0;
-          fm->next_ack = GNUNET_TIME_absolute_get();
-
-          if (pm->transmit_cont != NULL) {
-            pid = session->target;
-            pm->transmit_cont(pm->transmit_cont_cls, &pid,
-                GNUNET_OK);
-#if DEBUG_wlan
-              GNUNET_log(GNUNET_ERROR_TYPE_DEBUG, "called pm->transmit_cont for %p\n", session);
-#endif
-            }
-          else
-            {
-#if DEBUG_wlan
-              GNUNET_log(GNUNET_ERROR_TYPE_DEBUG, "no pm->transmit_cont for %p\n", session);
-#endif
-            }
-          GNUNET_free(pm);
-
-          sort_fragment_into_queue(plugin, fm);
-          plugin->pending_fragment_messages++;
-
-          //generate new message id
-          session->message_id_out = get_next_message_id();
-
-          //check if timeout changed
-          check_next_fragment_timeout(plugin);
-        }
+      header->rate = endpoint->rate;
+      header->tx_power = endpoint->tx_power;
+      header->antenna = endpoint->antenna;
+    }
+  else
+    {
+      header->rate = 255;
+      header->tx_power = 0;
+      header->antenna = 0;
     }
+
+  return GNUNET_YES;
 }
 
 /**
- * Funktion to check if all fragments where send and the acks received
- * frees the space if finished
- * @param plugin the plugin struct
- * @param fm the message to check
+ * function to generate the wlan hardware header for one packet
+ * @param Header address to write the header to
+ * @param to_mac_addr address of the recipient
+ * @param plugin pointer to the plugin struct
+ * @return GNUNET_YES if there was no error
  */
-static void
-check_finished_fragment(struct Plugin * plugin, struct FragmentMessage * fm)
+static int
+getWlanHeader(struct ieee80211_frame * Header,
+    const struct MacAddress * to_mac_addr, struct Plugin * plugin,
+    unsigned int size)
 {
-  struct AckQueue * ack;
-  int counter = 0;
-
-  if (fm->message_size >= (WLAN_MTU - sizeof(struct FragmentationHeader))
-      * fm->tail->fragment_num)
+  uint16_t * tmp16;
+  const int rate = 11000000;
+
+  Header->i_fc[0] = IEEE80211_FC0_TYPE_DATA;
+  Header->i_fc[1] = 0x00;
+  memcpy(&Header->i_addr3, &mac_bssid, sizeof(mac_bssid));
+  memcpy(&Header->i_addr2, plugin->mac_address.mac, sizeof(plugin->mac_address));
+  memcpy(&Header->i_addr1, to_mac_addr, sizeof(struct MacAddress));
+
+  tmp16 = (uint16_t*) Header->i_dur;
+  *tmp16 = (uint16_t) htole16((size * 1000000) / rate + 290);
+
+#if DEBUG_wlan_ip_udp_packets_on_air
+  uint crc = 0;
+  uint16_t * x;
+  int count;
+  Header->ip.ip_dst.s_addr = *((uint32_t*) &to_mac_addr->mac[2]);
+  Header->ip.ip_src.s_addr = *((uint32_t*) &plugin->mac_address.mac[2]);
+  Header->ip.ip_v = 4;
+  Header->ip.ip_hl = 5;
+  Header->ip.ip_p = 17;
+  Header->ip.ip_ttl = 1;
+  Header->ip.ip_len = htons(size + 8);
+  Header->ip.ip_sum = 0;
+  x =(uint16_t *) &Header->ip;
+  count = sizeof(struct iph);
+  while (count > 1)
     {
-      ack = fm->head;
-      counter = 0;
-      //check if all acks are present
-      while (ack != NULL)
-        {
-          if (counter == ack->fragment_num)
-            {
-              counter++;
-              ack = ack->next;
-            }
-          else
-            {
-              //ack is missing
-              return;
-            }
-        }
-      fm->session->has_fragment = 0;
-      free_fragment_message(plugin, fm);
+      /* This is the inner loop */
+      crc += (unsigned short) * x++;
+      count -= 2;
+    }
+  /* Add left-over byte, if any */
+  if( count > 0 )
+  crc += * (unsigned char *) x;
+  crc = (crc & 0xffff) + (crc >> 16);
+  Header->ip.ip_sum = htons(~ (unsigned short) crc);
+  Header->llc[0] = 6;
+  Header->llc[1] = 6;
+  Header->udp.len = htons(size - sizeof(struct ieee80211_frame));
 
-#if DEBUG_wlan
-      GNUNET_log(GNUNET_ERROR_TYPE_DEBUG, "Finished a fragmented message\n");
 #endif
 
+  return GNUNET_YES;
+}
+
+/**
+ * 32bit CRC
+ *
+ * @param msgbuf pointer tor the data
+ * @param msgbuf_size size of the data
+ *
+ * @return 32bit crc value
+ */
+
+uint32_t
+getcrc32(const char *msgbuf, size_t msgbuf_size)
+{
 
-      check_next_fragment_timeout(plugin);
+  return GNUNET_CRYPTO_crc32_n(msgbuf, msgbuf_size);;
+}
 
-    }
+/**
+ * 16bit CRC
+ *
+ * @param msgbuf pointer tor the data
+ * @param msgbuf_size size of the data
+ *
+ * @return 16bit crc value
+ */
+
+uint16_t
+getcrc16(const char *msgbuf, size_t msgbuf_size)
+{
+  //TODO calc some crc
+  return 0;
 }
 
 /**
- * Function to set the next fragment number
- * @param fm use this FragmentMessage
+ * function to add a fragment of a message to send
+ * @param cls FragmentMessage this message belongs to
+ * @param hdr pointer to the start of the message
  */
 
 void
-set_next_message_fragment_pos(struct FragmentMessage * fm)
+add_message_for_send(void *cls, const struct GNUNET_MessageHeader *hdr)
 {
-  struct AckQueue * akt = NULL;
-  //check if retransmit is needed
-  if (GNUNET_TIME_absolute_get_remaining(fm->next_ack).rel_value == 0)
-    {
 
-      // be positive and try again later :-D
-      fm->next_ack = GNUNET_TIME_relative_to_absolute(get_ack_timeout(fm));
-      // find first missing fragment
+  struct FragmentMessage * fm = cls;
+  struct FragmentMessage_queue * fmqueue;
 
-      fm->message_pos = 0;
-    }
+  GNUNET_assert(cls != NULL);
+  GNUNET_assert(fm->frag == NULL);
+  struct MacEndpoint * endpoint = fm->session->mac;
+  struct Plugin * plugin = endpoint->plugin;
+  struct GNUNET_MessageHeader * msgheader;
+  struct GNUNET_MessageHeader * msgheader2;
+  uint16_t size;
 
-  akt = fm->head;
-  //test if ack 0 (or X) was already received
-  while (akt != NULL)
-    {
-      //if fragment is present, take next
-      if (akt->fragment_num == fm->message_pos)
-        {
-          fm->message_pos++;
-        }
-      //next ack is bigger then the fragment number
-      //in case there is something like this: (acks) 1, 2, 5, 6, ...
-      //and we send 3 again, the next number should be 4
-      else if (akt->fragment_num > fm->message_pos)
-        {
-          break;
-        }
+#if DEBUG_wlan_retransmission
+  GNUNET_log(GNUNET_ERROR_TYPE_DEBUG,
+      "Adding fragment of message %p to send, session %p, endpoint %p\n", fm,
+      fm->session, endpoint);
+#endif
 
-      akt = akt->next;
+  size = sizeof(struct GNUNET_MessageHeader) + sizeof(struct Radiotap_Send)
+      + sizeof(struct ieee80211_frame) + ntohs(hdr->size);
+  fm->frag = GNUNET_malloc(size);
+  fm->size = size;
 
-    }
+  msgheader = (struct GNUNET_MessageHeader *) fm->frag;
+  msgheader->size = htons(size);
+  msgheader->type = htons(GNUNET_MESSAGE_TYPE_WLAN_HELPER_DATA);
 
+  fm->radioHeader = (struct Radiotap_Send*) &msgheader[1];
+  fm->ieeewlanheader = (struct ieee80211_frame*) &fm->radioHeader[1];
+  msgheader2 = (struct GNUNET_MessageHeader*) &fm->ieeewlanheader[1];
+  memcpy(msgheader2, hdr, ntohs(hdr->size));
+
+  fmqueue = GNUNET_malloc(sizeof(struct FragmentMessage_queue));
+  fmqueue->content = fm;
+
+  GNUNET_CONTAINER_DLL_insert_tail(plugin->sending_messages_head,
+      plugin->sending_messages_tail, fmqueue);
+  set_next_send(plugin);
 }
 
-void
+/**
+ * function to send a hallo beacon
+ * @param plugin pointer to the plugin struct
+ */
+static void
 send_hello_beacon(struct Plugin * plugin)
 {
 
@@ -1163,90 +1317,39 @@ send_hello_beacon(struct Plugin * plugin)
   GNUNET_log(GNUNET_ERROR_TYPE_DEBUG, "Sending hello beacon\n");
 #endif
 
-   uint16_t size = 0;
-   ssize_t bytes;
-   struct GNUNET_MessageHeader * msgheader = NULL;
-   struct IeeeHeader * ieeewlanheader = NULL;
-   struct RadiotapHeader * radioHeader = NULL;
-   struct GNUNET_MessageHeader * msgheader2 = NULL;
-
-   GNUNET_assert(sizeof(struct WlanHeader) + GNUNET_HELLO_size(
-   *(plugin->env->our_hello)) <= WLAN_MTU);
-   size = sizeof(struct GNUNET_MessageHeader) + sizeof(struct RadiotapHeader)
-   + sizeof(struct IeeeHeader) + sizeof(struct GNUNET_MessageHeader)
-   + GNUNET_HELLO_size(*(plugin->env->our_hello));
-
-   msgheader = GNUNET_malloc(size);
-   msgheader->size = htons(size);
-   msgheader->type = htons(GNUNET_MESSAGE_TYPE_WLAN_HELPER_DATA);
-
-   radioHeader = (struct RadiotapHeader*) &msgheader[1];
-   getRadiotapHeader(radioHeader);
-   ieeewlanheader = (struct IeeeHeader*) &radioHeader[1];
-   getWlanHeader(ieeewlanheader, bc_all_mac, plugin);
-
-   msgheader2 = (struct GNUNET_MessageHeader*) &ieeewlanheader[1];
-   msgheader2->size = htons(GNUNET_HELLO_size(*(plugin->env->our_hello))
-   + sizeof(struct GNUNET_MessageHeader));
-
-   msgheader2->type = htons(GNUNET_MESSAGE_TYPE_WLAN_ADVERTISEMENT);
-   memcpy(&msgheader2[1], *plugin->env->our_hello, GNUNET_HELLO_size(
-   *(plugin->env->our_hello)));
-
-   bytes = GNUNET_DISK_file_write(plugin->server_stdin_handle, msgheader, size);
-
-   if (bytes == GNUNET_SYSERR)
-   {
-   GNUNET_log(GNUNET_ERROR_TYPE_ERROR,
-   _("Error writing to wlan healper. errno == %d, ERROR: %s\n"),
-   errno, strerror(errno));
-
-   }
-   GNUNET_assert(bytes != GNUNET_SYSERR);
-   GNUNET_assert(bytes == size);
-   GNUNET_free(msgheader);
-
-  set_next_beacon_time(plugin);
-  check_next_fragment_timeout(plugin);
-}
-
-static void
-send_ack(struct Plugin * plugin, struct AckSendQueue * ack)
-{
-
-  uint16_t size = 0;
+  uint16_t size;
   ssize_t bytes;
-  struct GNUNET_MessageHeader * msgheader = NULL;
-  struct IeeeHeader * ieeewlanheader = NULL;
-  struct RadiotapHeader * radioHeader = NULL;
-  struct FragmentationHeader * msgheader2 = NULL;
-
-  GNUNET_assert(sizeof(struct FragmentationHeader) <= WLAN_MTU);
-
-#if DEBUG_wlan
-  GNUNET_log(GNUNET_ERROR_TYPE_DEBUG,
-      "Sending ack for message_id %u with fragment number %u\n",
-      ack->message_id, ack->fragment_off_or_num);
-#endif
+  uint16_t hallo_size;
+  struct GNUNET_MessageHeader * msgheader;
+  struct ieee80211_frame * ieeewlanheader;
+  struct Radiotap_Send * radioHeader;
+  struct GNUNET_MessageHeader * msgheader2;
+
+  hallo_size = GNUNET_HELLO_size(*(plugin->env->our_hello));
+  GNUNET_assert(sizeof(struct WlanHeader) + hallo_size <= WLAN_MTU);
+  size = sizeof(struct GNUNET_MessageHeader) + sizeof(struct Radiotap_Send)
+      + sizeof(struct ieee80211_frame) + sizeof(struct GNUNET_MessageHeader)
+      + hallo_size;
 
-  size = sizeof(struct GNUNET_MessageHeader) + sizeof(struct RadiotapHeader)
-      + sizeof(struct IeeeHeader) + sizeof(struct FragmentationHeader);
   msgheader = GNUNET_malloc(size);
   msgheader->size = htons(size);
   msgheader->type = htons(GNUNET_MESSAGE_TYPE_WLAN_HELPER_DATA);
 
-  radioHeader = (struct RadiotapHeader*) &msgheader[1];
-  getRadiotapHeader(radioHeader);
-  ieeewlanheader = (struct IeeeHeader*) &radioHeader[1];
-  getWlanHeader(ieeewlanheader, ack->session->addr, plugin);
+  radioHeader = (struct Radiotap_Send*) &msgheader[1];
+  getRadiotapHeader(plugin, NULL, radioHeader);
+  ieeewlanheader = (struct ieee80211_frame*) &radioHeader[1];
+  getWlanHeader(ieeewlanheader, &bc_all_mac, plugin, size);
+
+  msgheader2 = (struct GNUNET_MessageHeader*) &ieeewlanheader[1];
+  msgheader2->size = htons(
+      GNUNET_HELLO_size(*(plugin->env->our_hello))
+          + sizeof(struct GNUNET_MessageHeader));
 
-  msgheader2 = (struct FragmentationHeader*) &ieeewlanheader[1];
-  msgheader2->header.size = htons(sizeof(struct FragmentationHeader));
-  msgheader2->header.type = htons(GNUNET_MESSAGE_TYPE_WLAN_FRAGMENT_ACK);
-  msgheader2->message_id = htonl(ack->message_id);
-  msgheader2->fragment_off_or_num = htons(ack->fragment_off_or_num);
+  msgheader2->type = htons(GNUNET_MESSAGE_TYPE_WLAN_ADVERTISEMENT);
+  memcpy(&msgheader2[1], *plugin->env->our_hello, hallo_size);
 
   bytes = GNUNET_DISK_file_write(plugin->server_stdin_handle, msgheader, size);
+
   if (bytes == GNUNET_SYSERR)
     {
       GNUNET_log(GNUNET_ERROR_TYPE_ERROR,
@@ -1257,228 +1360,197 @@ send_ack(struct Plugin * plugin, struct AckSendQueue * ack)
   GNUNET_assert(bytes != GNUNET_SYSERR);
   GNUNET_assert(bytes == size);
   GNUNET_free(msgheader);
-  check_next_fragment_timeout(plugin);
+
+  set_next_beacon_time(plugin);
+  set_next_send(plugin);
 }
 
 /**
- * Function called when wlan helper is ready to get some data
+ * function to add an ack to send it for a received fragment
+ * @param cls MacEndpoint this ack belongs to
+ * @param msg_id id of the message
+ * @param hdr pointer to the hdr where the ack is stored
  *
- * @param cls closure
- * @param tc GNUNET_SCHEDULER_TaskContext
  */
 
 static void
-do_transmit(void *cls, const struct GNUNET_SCHEDULER_TaskContext *tc)
+add_ack_for_send(void *cls, uint32_t msg_id,
+    const struct GNUNET_MessageHeader *hdr)
 {
 
-  struct Plugin * plugin = cls;
-  plugin->server_write_task = GNUNET_SCHEDULER_NO_TASK;
-
-  if (tc->reason == GNUNET_SCHEDULER_REASON_SHUTDOWN)
-    return;
+  struct AckSendQueue * ack;
 
-  struct Session * session = NULL;
-  struct FragmentMessage * fm = NULL;
-  struct IeeeHeader * ieeewlanheader = NULL;
-  struct RadiotapHeader * radioHeader = NULL;
-  struct GNUNET_MessageHeader * msgheader = NULL;
+  GNUNET_assert(cls != NULL);
+  struct MacEndpoint * endpoint = cls;
+  struct Plugin * plugin = endpoint->plugin;
+  struct GNUNET_MessageHeader * msgheader;
+  struct GNUNET_MessageHeader * msgheader2;
+  uint16_t size;
 
-  struct FragmentationHeader fragheader;
-  struct FragmentationHeader * fragheaderptr = NULL;
-  struct Finish_send * finish = NULL;
-  struct AckSendQueue * ack;
-  uint16_t size = 0;
-  ssize_t bytes;
-  const char * copystart = NULL;
-  uint16_t copysize = 0;
-  uint copyoffset = 0;
+  size = sizeof(struct GNUNET_MessageHeader) + sizeof(struct Radiotap_Send)
+      + sizeof(struct ieee80211_frame) + ntohs(hdr->size)
+      + sizeof(struct AckSendQueue);
 
-  if (plugin->ack_send_queue_head != NULL)
-    {
-      ack = plugin->ack_send_queue_head;
-      GNUNET_CONTAINER_DLL_remove(plugin->ack_send_queue_head,
-          plugin->ack_send_queue_tail, ack);
-      send_ack(plugin, ack);
-      GNUNET_free(ack);
-      return;
-    }
+  ack = GNUNET_malloc(size);
+  ack->message_id = msg_id;
+  ack->endpoint = endpoint;
 
-  //test if a "hello-beacon" has to be send
-  if (GNUNET_TIME_absolute_get_remaining(plugin->beacon_time).rel_value == 0)
-    {
-      send_hello_beacon(plugin);
+  size = sizeof(struct GNUNET_MessageHeader) + sizeof(struct Radiotap_Send)
+      + sizeof(struct ieee80211_frame) + ntohs(hdr->size);
 
-      return;
+  msgheader = (struct GNUNET_MessageHeader *) &ack[1];
+  ack->hdr = (struct GNUNET_MessageHeader *) &ack[1];
+  msgheader->size = htons(size);
+  msgheader->type = htons(GNUNET_MESSAGE_TYPE_WLAN_HELPER_DATA);
 
-    }
+  ack->radioHeader = (struct Radiotap_Send*) &msgheader[1];
+  ack->ieeewlanheader = (struct ieee80211_frame*) &(ack->radioHeader)[1];
+  msgheader2 = (struct GNUNET_MessageHeader*) &(ack->ieeewlanheader)[1];
+  memcpy(msgheader2, hdr, ntohs(hdr->size));
 
-  fm = plugin->pending_Fragment_Messages_head;
-  if (fm != NULL)
-    {
-      session = fm->session;
-      GNUNET_assert(session != NULL);
+  GNUNET_CONTAINER_DLL_insert_tail(plugin->ack_send_queue_head,
+      plugin->ack_send_queue_tail, ack);
 
-      // test if message timed out
-      if (GNUNET_TIME_absolute_get_remaining(fm->timeout).rel_value == 0)
-        {
-#if DEBUG_wlan
-          GNUNET_log(GNUNET_ERROR_TYPE_DEBUG, "message timeout\n");
+#if DEBUG_wlan_retransmission
+  GNUNET_log(GNUNET_ERROR_TYPE_DEBUG,
+      "Adding ack with message id %u to send, AckSendQueue %p, endpoint %p\n",
+      msg_id, ack, endpoint);
 #endif
-          free_acks(fm);
-          GNUNET_assert(plugin->pending_fragment_messages > 0);
-          plugin->pending_fragment_messages--;
-          GNUNET_CONTAINER_DLL_remove(plugin->pending_Fragment_Messages_head,
-              plugin->pending_Fragment_Messages_tail, fm);
 
-          GNUNET_free(fm->msg);
+  set_next_send(plugin);
+}
 
-          GNUNET_free(fm);
-          check_fragment_queue(plugin);
-        }
-      else
+/**
+ * Function to check if there is some space in the fragment queue
+ * inserts a message if space is available
+ * @param plugin the plugin struct
+ */
+
+static void
+check_fragment_queue(struct Plugin * plugin)
+{
+  struct Session * session;
+  struct FragmentMessage * fm;
+  struct GNUNET_PeerIdentity pid;
+
+  struct PendingMessage * pm;
+
+  if (plugin->pending_Fragment_Messages < FRAGMENT_QUEUE_SIZE)
+    {
+      session = get_next_queue_session(plugin);
+      if (session != NULL)
         {
+          pm = session->pending_message_head;
+          GNUNET_CONTAINER_DLL_remove(session->pending_message_head, session->pending_message_tail, pm);
+          session->mac->fragment_messages_out_count++;
+          session->fragment_messages_out_count++;
+          plugin->pending_Fragment_Messages++;
+          GNUNET_assert(pm != NULL);
 
-          //if (fm->message_size > WLAN_MTU)
-          // {
-          size += sizeof(struct FragmentationHeader);
-
-          set_next_message_fragment_pos(fm);
-
-          copyoffset = (WLAN_MTU - sizeof(struct FragmentationHeader))
-              * fm->message_pos;
-          fragheader.fragment_off_or_num = htons(fm->message_pos);
-          fragheader.message_id = htonl(session->message_id_out);
-          GNUNET_assert(copyoffset < fm->message_size);
-          copystart = fm->msg + copyoffset;
-          copysize = GNUNET_MIN(fm->message_size - copyoffset,
-              WLAN_MTU - sizeof(struct FragmentationHeader));
-          fragheader.header.size = htons(copysize
-              + sizeof(struct FragmentationHeader));
-          fragheader.header.type = htons(GNUNET_MESSAGE_TYPE_WLAN_FRAGMENT);
-
-          /* }
-           else
-           {
-           // there is no need to split
-           copystart = fm->msg;
-           copysize = fm->message_size;
-           }*/
+          fm = GNUNET_malloc(sizeof(struct FragmentMessage));
+          fm->session = session;
+          fm->timeout.abs_value = pm->timeout.abs_value;
+          fm->frag = NULL;
+          fm->fragcontext = GNUNET_FRAGMENT_context_create(plugin->env->stats,
+              WLAN_MTU, &plugin->tracker, GNUNET_TIME_UNIT_SECONDS,
+              &(pm->msg->header), &add_message_for_send,
+              fm);
+          GNUNET_CONTAINER_DLL_insert_tail(session->mac->sending_messages_head,session->mac->sending_messages_tail,fm);
 
+          if (pm->transmit_cont != NULL)
+            {
+              pid = session->target;
+              pm->transmit_cont(pm->transmit_cont_cls, &pid, GNUNET_OK);
 #if DEBUG_wlan
-          GNUNET_log(
-              GNUNET_ERROR_TYPE_DEBUG,
-              "Sending GNUNET_MESSAGE_TYPE_WLAN_FRAGMENT with message_id %u with fragment number %i, size: %u, time until timeout %u\n",
-              session->message_id_out, fm->message_pos, copysize
-                  + sizeof(struct FragmentationHeader),
-              GNUNET_TIME_absolute_get_remaining(fm->timeout));
+              GNUNET_log(GNUNET_ERROR_TYPE_DEBUG,
+                  "called pm->transmit_cont for %p\n", session);
 #endif
-
-          size += copysize;
-          size += sizeof(struct RadiotapHeader) + sizeof(struct IeeeHeader)
-              + sizeof(struct GNUNET_MessageHeader);
-          msgheader = GNUNET_malloc(size);
-          msgheader->size = htons(size);
-          msgheader->type = htons(GNUNET_MESSAGE_TYPE_WLAN_HELPER_DATA);
-
-          radioHeader = (struct RadiotapHeader*) &msgheader[1];
-          getRadiotapHeader(radioHeader);
-
-          ieeewlanheader = (struct IeeeHeader *) &radioHeader[1];
-          getWlanHeader(ieeewlanheader, fm->session->addr, plugin);
-
-          //could be faster if content is just send and not copyed before
-          //fragmentheader is needed
-          //if (fm->message_size > WLAN_MTU)
-          // {
-          fragheader.message_crc = htons(getcrc16(copystart, copysize));
-          memcpy(&ieeewlanheader[1], &fragheader,
-              sizeof(struct FragmentationHeader));
-          fragheaderptr = (struct FragmentationHeader *) &ieeewlanheader[1];
-          memcpy(&fragheaderptr[1], copystart, copysize);
-          /* }
-           else
-           {
-           memcpy(&ieeewlanheader[1], copystart, copysize);
-           }*/
-
-          bytes = GNUNET_DISK_file_write(plugin->server_stdin_handle,
-              msgheader, size);
-          if (bytes == GNUNET_SYSERR)
+            }
+          else
             {
-              GNUNET_log(
-                  GNUNET_ERROR_TYPE_ERROR,
-                  _("Error writing to wlan healper. errno == %d, ERROR: %s\n"),
-                  errno, strerror(errno));
-
+#if DEBUG_wlan
+              GNUNET_log(GNUNET_ERROR_TYPE_DEBUG,
+                  "no pm->transmit_cont for %p\n", session);
+#endif
             }
-          GNUNET_assert(bytes != GNUNET_SYSERR);
+          GNUNET_free(pm);
 
-          if (bytes != size)
+          if (session->pending_message_head != NULL)
             {
-              finish = GNUNET_malloc(sizeof( struct Finish_send));
-              finish->plugin = plugin;
-              finish->msgheader = (char *) msgheader + bytes;
-              finish->size = size - bytes;
-              finish->msgstart = msgheader;
-
-              GNUNET_assert(plugin->server_write_task == GNUNET_SCHEDULER_NO_TASK);
+              //requeue session
+              queue_session(plugin, session);
+            }
 
-              plugin->server_write_task = GNUNET_SCHEDULER_add_write_file(
-                  GNUNET_TIME_UNIT_FOREVER_REL, plugin->server_stdin_handle,
-                  &finish_sending, finish);
+        }
+    }
 
-            }
-          else
-            {
-              GNUNET_assert(bytes == size);
+  //check if timeout changed
+  set_next_send(plugin);
+}
 
-              GNUNET_free(msgheader);
-              check_next_fragment_timeout(plugin);
-            }
+/**
+ * Function to send an ack, does not free the ack
+ * @param plugin pointer to the plugin
+ * @param ack pointer to the ack to send
+ */
+static void
+send_ack(struct Plugin * plugin, struct AckSendQueue * ack)
+{
 
-          //check if this was the last fragment of this message, if true then queue at the end of the list
-          if (copysize + copyoffset >= fm->message_size)
-            {
-              GNUNET_assert(copysize + copyoffset == fm->message_size);
+  ssize_t bytes;
 
-              GNUNET_CONTAINER_DLL_remove (plugin->pending_Fragment_Messages_head,
-                  plugin->pending_Fragment_Messages_tail, fm);
+#if DEBUG_wlan
+  GNUNET_log(GNUNET_ERROR_TYPE_DEBUG,
+      "Sending ack for message_id %u for mac endpoint %p, size %u\n",
+      ack->message_id, ack->endpoint,
+      ntohs(ack->hdr->size) - sizeof(struct Radiotap_Send));
+#endif
 
-              GNUNET_CONTAINER_DLL_insert_tail(plugin->pending_Fragment_Messages_head,
-                  plugin->pending_Fragment_Messages_tail, fm);
-              // if fragments have opimized timeouts
-              //sort_fragment_into_queue(plugin,fm);
+  getRadiotapHeader(plugin, ack->endpoint, ack->radioHeader);
+  getWlanHeader(ack->ieeewlanheader, &ack->endpoint->addr, plugin,
+      ntohs(ack->hdr->size));
 
-            }
+  bytes = GNUNET_DISK_file_write(plugin->server_stdin_handle, ack->hdr,
+      ntohs(ack->hdr->size));
+  if (bytes == GNUNET_SYSERR)
+    {
+      GNUNET_log(GNUNET_ERROR_TYPE_ERROR,
+          _("Error writing to wlan healper. errno == %d, ERROR: %s\n"),
+          errno, strerror(errno));
 
-        }
-      return;
     }
-  GNUNET_log(GNUNET_ERROR_TYPE_WARNING,
-      "do_transmit did nothing, should not happen!\n");
+  GNUNET_assert(bytes != GNUNET_SYSERR);
+  GNUNET_assert(bytes == ntohs(ack->hdr->size));
+  set_next_send(plugin);
 }
 
+/**
+ * function to finish a sending if not all could have been writen befor
+ * @param cls pointer to the Finish_send struct
+ * @param tc TaskContext
+ */
 static void
 finish_sending(void *cls, const struct GNUNET_SCHEDULER_TaskContext *tc)
 {
-  struct Finish_send * finish;
+  struct Finish_send * finish = cls;
   struct Plugin * plugin;
   ssize_t bytes;
 
-  finish = cls;
   plugin = finish->plugin;
-
   plugin->server_write_task = GNUNET_SCHEDULER_NO_TASK;
 
+  if (0 != (GNUNET_SCHEDULER_REASON_SHUTDOWN & tc->reason))
+    {
+      GNUNET_free (finish->msgstart);
+      GNUNET_free (finish);
+      return;
+    }
   bytes = GNUNET_DISK_file_write(plugin->server_stdin_handle,
       finish->msgheader, finish->size);
-  GNUNET_assert(bytes != GNUNET_SYSERR);
+  GNUNET_assert (bytes != GNUNET_SYSERR);
 
-  GNUNET_assert(plugin->server_write_task == GNUNET_SCHEDULER_NO_TASK);
   if (bytes != finish->size)
     {
-
-      finish->plugin = plugin;
       finish->msgheader = finish->msgheader + bytes;
       finish->size = finish->size - bytes;
       plugin->server_write_task = GNUNET_SCHEDULER_add_write_file(
@@ -1489,66 +1561,140 @@ finish_sending(void *cls, const struct GNUNET_SCHEDULER_TaskContext *tc)
     {
       GNUNET_free(finish->msgstart);
       GNUNET_free(finish);
-      check_next_fragment_timeout(plugin);
+      set_next_send(plugin);
     }
-
 }
 
-int
-getRadiotapHeader(struct RadiotapHeader * Header)
-{
-  return GNUNET_YES;
-}
-;
-
 /**
- * function to generate the wlan hardware header for one packet
- * @param Header address to write the header to
- * @param to_mac_addr address of the recipient
- * @param plugin pointer to the plugin struct
- * @return GNUNET_YES if there was no error
+ * Function called when wlan helper is ready to get some data
+ *
+ * @param cls closure
+ * @param tc GNUNET_SCHEDULER_TaskContext
  */
-
-int
-getWlanHeader(struct IeeeHeader * Header,const char * const to_mac_addr,
-    struct Plugin * plugin)
+static void
+do_transmit(void *cls, const struct GNUNET_SCHEDULER_TaskContext *tc)
 {
-  memcpy(&Header->mac2, macbc, sizeof(macbc));
-  memcpy(&Header->mac3, plugin->mac_address.mac, sizeof(plugin->mac_address));
-  memcpy(&Header->mac1, to_mac_addr, sizeof(plugin->mac_address));
-  return GNUNET_YES;
-}
+  struct Plugin * plugin = cls;
 
-/**
- * 32bit CRC
- *
- * @param msgbuf pointer tor the data
- * @param msgbuf_size size of the data
- *
- * @return 32bit crc value
- */
+  plugin->server_write_task = GNUNET_SCHEDULER_NO_TASK;
+  if (0 != (tc->reason & GNUNET_SCHEDULER_REASON_SHUTDOWN))
+    return;
 
-uint32_t
-getcrc32(const char *msgbuf, size_t msgbuf_size)
-{
-  //TODO calc some crc
-  return 0;
+  struct Session * session;
+  struct FragmentMessage * fm;
+  struct Finish_send * finish;
+  struct FragmentMessage_queue * fmq;
+  struct AckSendQueue * ack;
+  ssize_t bytes;
+
+  if (plugin->ack_send_queue_head != NULL)
+    {
+      ack = plugin->ack_send_queue_head;
+      GNUNET_CONTAINER_DLL_remove(plugin->ack_send_queue_head,
+          plugin->ack_send_queue_tail, ack);
+      send_ack(plugin, ack);
+      GNUNET_free(ack);
+      return;
+    }
+
+  //test if a "hello-beacon" has to be send
+  if (GNUNET_TIME_absolute_get_remaining(plugin->beacon_time).rel_value == 0)
+    {
+      send_hello_beacon(plugin);
+      return;
+    }
+
+  if (plugin->sending_messages_head != NULL)
+    {
+      fmq = plugin->sending_messages_head;
+      fm = fmq->content;
+      GNUNET_CONTAINER_DLL_remove(plugin->sending_messages_head,plugin->sending_messages_tail,fmq);
+      GNUNET_free(fmq);
+
+      session = fm->session;
+      GNUNET_assert(session != NULL);
+
+#if DEBUG_wlan
+      GNUNET_log(
+          GNUNET_ERROR_TYPE_DEBUG,
+          "Sending GNUNET_MESSAGE_TYPE_WLAN_FRAGMENT for fragment message %p, size: %u\n",
+          fm, fm->size);
+#endif
+
+      getRadiotapHeader(plugin, session->mac, fm->radioHeader);
+      getWlanHeader(fm->ieeewlanheader, &(fm->session->mac->addr), plugin,
+          fm->size);
+
+      bytes = GNUNET_DISK_file_write(plugin->server_stdin_handle, fm->frag,
+          fm->size);
+      if (bytes == GNUNET_SYSERR)
+        {
+          GNUNET_log(GNUNET_ERROR_TYPE_ERROR,
+              _("Error writing to wlan healper. errno == %d, ERROR: %s\n"),
+              errno, strerror(errno));
+
+        }
+      GNUNET_assert(bytes != GNUNET_SYSERR);
+
+      if (bytes != fm->size)
+        {
+          finish = GNUNET_malloc(sizeof( struct Finish_send));
+          finish->plugin = plugin;
+          finish->msgheader = fm->frag + bytes;
+          finish->size = fm->size - bytes;
+          finish->msgstart = (struct GNUNET_MessageHeader *) fm->frag;
+
+          GNUNET_assert(plugin->server_write_task == GNUNET_SCHEDULER_NO_TASK);
+
+          plugin->server_write_task = GNUNET_SCHEDULER_add_write_file(
+              GNUNET_TIME_UNIT_FOREVER_REL, plugin->server_stdin_handle,
+              &finish_sending, finish);
+          fm->frag = NULL;
+        }
+      else
+        {
+          GNUNET_free(fm->frag);
+          fm->frag = NULL;
+          set_next_send(plugin);
+        }
+      GNUNET_FRAGMENT_context_transmission_done (fm->fragcontext);
+      return;
+    }
+
+  GNUNET_log(GNUNET_ERROR_TYPE_WARNING,
+      "do_transmit did nothing, should not happen!\n");
 }
 
 /**
- * 16bit CRC
- *
- * @param msgbuf pointer tor the data
- * @param msgbuf_size size of the data
+ * Another peer has suggested an address for this
+ * peer and transport plugin.  Check that this could be a valid
+ * address.  If so, consider adding it to the list
+ * of addresses.
  *
- * @return 16bit crc value
+ * @param cls closure
+ * @param addr pointer to the address
+ * @param addrlen length of addr
+ * @return GNUNET_OK if this is a plausible address for this peer
+ *         and transport
  */
-
-uint16_t
-getcrc16(const char *msgbuf, size_t msgbuf_size)
+static int
+wlan_plugin_address_suggested(void *cls, const void *addr, size_t addrlen)
 {
-  //TODO calc some crc
-  return 0;
+  //struct Plugin *plugin = cls;
+
+  /* check if the address is plausible; if so,
+   add it to our list! */
+
+  GNUNET_assert(cls !=NULL);
+  //FIXME mitm is not checked
+  //Mac Address has 6 bytes
+  if (addrlen == 6)
+    {
+      /* TODO check for bad addresses like multicast, broadcast, etc */
+      return GNUNET_OK;
+    }
+
+  return GNUNET_SYSERR;
 }
 
 /**
@@ -1560,7 +1706,7 @@ getcrc16(const char *msgbuf, size_t msgbuf_size)
  * @param priority how important is the message
  * @param msgbuf the message to transmit
  * @param msgbuf_size number of bytes in 'msgbuf'
- * @param timeout when should we time out 
+ * @param timeout when should we time out
  * @param session which session must be used (or NULL for "any")
  * @param addr the address to use (can be NULL if the plugin
  *                is "on its own" (i.e. re-use existing TCP connection))
@@ -1585,10 +1731,8 @@ wlan_plugin_send(void *cls, const struct GNUNET_PeerIdentity * target,
     GNUNET_TRANSPORT_TransmitContinuation cont, void *cont_cls)
 {
   struct Plugin * plugin = cls;
-  struct PendingMessage * newmsg = NULL;
-  struct WlanHeader * wlanheader = NULL;
-  //struct GNUNET_MessageHeader * innermsg =
-   //    (struct GNUNET_MessageHeader *) msgbuf;
+  struct PendingMessage * newmsg;
+  struct WlanHeader * wlanheader;
 
   //check if msglen > 0
   GNUNET_assert(msgbuf_size > 0);
@@ -1598,7 +1742,7 @@ wlan_plugin_send(void *cls, const struct GNUNET_PeerIdentity * target,
     {
       if (wlan_plugin_address_suggested(plugin, addr, addrlen) == GNUNET_OK)
         {
-          session = get_Session(plugin, addr);
+          session = get_session(plugin, addr, target);
         }
       else
         {
@@ -1608,44 +1752,37 @@ wlan_plugin_send(void *cls, const struct GNUNET_PeerIdentity * target,
         }
     }
 
-#if DEBUG_wlan
-  GNUNET_log(
-      GNUNET_ERROR_TYPE_DEBUG,
-      "wlan_plugin_send got %u bytes data, packet says it has %u bytes for %.2X:%.2X:%.2X:%.2X:%.2X:%.2X\n",
-      msgbuf_size, ntohs(innermsg->size), session->addr[0], session->addr[1],
-      session->addr[2], session->addr[3], session->addr[4], session->addr[5]);
-#endif
-
-  //TODO target "problem" not solved
-  session->target = *target;
-
   //queue message:
-  //first queue session
-  queue_Session(plugin, session);
 
   //queue message in session
   //test if there is no other message in the "queue"
   //FIXME: to many send requests
-  //GNUNET_assert (session->pending_message == NULL);
-  if (session->pending_message != NULL)
+  if (session->pending_message_head != NULL)
     {
-      newmsg = session->pending_message;
+      newmsg = session->pending_message_head;
       GNUNET_log(
           GNUNET_ERROR_TYPE_ERROR,
-          "wlan_plugin_send: a pending message is already in the queue for this client\n remaining time to send this message is %u\n",
-          GNUNET_TIME_absolute_get_remaining(newmsg->timeout).rel_value);
-      return -1;
+          "wlan_plugin_send: a pending message is already in the queue for this client\n remaining time to send this message is %u, queued fragment messages for this mac connection %u\n",
+          GNUNET_TIME_absolute_get_remaining(newmsg->timeout).rel_value,
+          session->mac->fragment_messages_out_count);
     }
 
   newmsg = GNUNET_malloc(sizeof(struct PendingMessage));
-  (newmsg->msg) = GNUNET_malloc(msgbuf_size + sizeof(struct WlanHeader));
-  wlanheader = (struct WlanHeader *) newmsg->msg;
+  newmsg->msg = GNUNET_malloc(msgbuf_size + sizeof(struct WlanHeader));
+  wlanheader = newmsg->msg;
   //copy msg to buffer, not fragmented / segmented yet, but with message header
   wlanheader->header.size = htons(msgbuf_size + sizeof(struct WlanHeader));
   wlanheader->header.type = htons(GNUNET_MESSAGE_TYPE_WLAN_DATA);
   memcpy(&(wlanheader->target), target, sizeof(struct GNUNET_PeerIdentity));
-  wlanheader->crc = htonl(getcrc32(msgbuf, msgbuf_size));
+  memcpy(&(wlanheader->source), plugin->env->my_identity,
+      sizeof(struct GNUNET_PeerIdentity));
+  wlanheader->crc = 0;
   memcpy(&wlanheader[1], msgbuf, msgbuf_size);
+  wlanheader->crc = htonl(
+      getcrc32((char*) wlanheader, msgbuf_size + sizeof(struct WlanHeader)));
+  //GNUNET_log(GNUNET_ERROR_TYPE_INFO, "Wlan message Header crc: %u, %u\n",getcrc32((char*) wlanheader, msgbuf_size + sizeof(struct WlanHeader)), wlanheader->crc);
+  //hexdump(newmsg->msg, msgbuf_size + sizeof(struct WlanHeader));
+
   newmsg->transmit_cont = cont;
   newmsg->transmit_cont_cls = cont_cls;
   newmsg->timeout = GNUNET_TIME_relative_to_absolute(timeout);
@@ -1654,7 +1791,16 @@ wlan_plugin_send(void *cls, const struct GNUNET_PeerIdentity * target,
 
   newmsg->message_size = msgbuf_size + sizeof(struct WlanHeader);
 
-  session->pending_message = newmsg;
+  GNUNET_CONTAINER_DLL_insert_tail(session->pending_message_head, session->pending_message_tail, newmsg);
+
+#if DEBUG_wlan
+  GNUNET_log(GNUNET_ERROR_TYPE_DEBUG,
+      "New message for %p with size (incl wlan header) %u added\n", session,
+      newmsg->message_size);
+#endif
+
+  //queue session
+  queue_session(plugin, session);
 
   check_fragment_queue(plugin);
   //FIXME not the correct size
@@ -1662,20 +1808,105 @@ wlan_plugin_send(void *cls, const struct GNUNET_PeerIdentity * target,
 
 }
 
-//TODO doxigen
-static struct FragmentMessage *
-get_fragment_message_from_session(struct Session * session)
+/**
+ * function to free a mac endpoint
+ * @param plugin pointer to the plugin struct
+ * @param endpoin pointer to the MacEndpoint to free
+ */
+static void
+free_macendpoint(struct Plugin * plugin, struct MacEndpoint * endpoin)
 {
-  struct FragmentMessage * fm = session->plugin->pending_Fragment_Messages_head;
+  struct Sessionqueue * sessions;
+  struct Sessionqueue * sessions_next;
+  GNUNET_assert(endpoin != NULL);
+
+  sessions = endpoin->sessions_head;
+  while (sessions != NULL)
+    {
+      sessions_next = sessions->next;
+      free_session(plugin, sessions, GNUNET_NO);
+      sessions = sessions_next;
+    }
+
+  GNUNET_CONTAINER_DLL_remove(plugin->mac_head,plugin->mac_tail,endpoin);
+  GNUNET_free(endpoin);
+
+}
+
+/**
+ * function to free a session
+ * @param plugin pointer to the plugin
+ * @param queue pointer to the sessionqueue element to free
+ * @param free_macendpoint if GNUNET_YES and mac endpoint would be empty, free mac endpoint
+ */
+static void
+free_session(struct Plugin * plugin, struct Sessionqueue * queue,
+    int do_free_macendpoint)
+{
+  struct Sessionqueue * pendingsession;
+  struct Sessionqueue * pendingsession_tmp;
+  struct PendingMessage * pm;
+  struct MacEndpoint * endpoint;
+  struct FragmentMessage * fm;
+  struct FragmentMessage * fmnext;
+  int check = 0;
+
+  GNUNET_assert(queue != NULL);
+  GNUNET_assert(queue->content != NULL);
+
+  //session found
+  //is this session pending for send
+  pendingsession = plugin->pending_Sessions_head;
+  while (pendingsession != NULL)
+    {
+      pendingsession_tmp = pendingsession->next;
+      if (pendingsession->content == queue->content)
+        {
+          plugin->pendingsessions--;
+          GNUNET_CONTAINER_DLL_remove (plugin->pending_Sessions_head,
+              plugin->pending_Sessions_tail,
+              pendingsession);
+          GNUNET_free(pendingsession);
+
+          GNUNET_assert (check == 0);
+          check = 1;
+        }
+      pendingsession = pendingsession_tmp;
+    }
+
+  endpoint = queue->content->mac;
+  fm = endpoint->sending_messages_head;
   while (fm != NULL)
     {
-      if (fm->session == session)
+      fmnext = fm->next;
+      if (fm->session == queue->content)
         {
-          return fm;
+          free_fragment_message(plugin, fm);
         }
-      fm = fm->next;
+      fm = fmnext;
     }
-  return NULL;
+
+  // remove PendingMessage
+  pm = queue->content->pending_message_head;
+  while (pm != NULL)
+    {
+      GNUNET_CONTAINER_DLL_remove(queue->content->pending_message_head,queue->content->pending_message_tail,pm);
+      GNUNET_free(pm->msg);
+      GNUNET_free(pm);
+      pm = queue->content->pending_message_head;
+    }
+
+  GNUNET_CONTAINER_DLL_remove(endpoint->sessions_head ,
+      endpoint->sessions_tail,
+      queue);
+
+  if (endpoint->sessions_head == NULL && do_free_macendpoint == GNUNET_YES)
+    {
+      free_macendpoint(plugin, endpoint);
+    }
+  GNUNET_free(queue->content);
+  GNUNET_free(queue);
+  check_fragment_queue(plugin);
 }
 
 /**
@@ -1690,58 +1921,29 @@ static void
 wlan_plugin_disconnect(void *cls, const struct GNUNET_PeerIdentity *target)
 {
   struct Plugin *plugin = cls;
-  struct Sessionqueue * queue = plugin->sessions;
-  struct Sessionqueue * pendingsession = plugin->pending_Sessions;
-  struct PendingMessage * pm = NULL;
-  struct FragmentMessage * fm;
-
+  struct Sessionqueue * queue;
+  struct Sessionqueue * queue_next;
+  struct MacEndpoint * endpoint = plugin->mac_head;
+  struct MacEndpoint * endpoint_next;
   // just look at all the session for the needed one
-  while (queue != NULL)
+  while (endpoint != NULL)
     {
-      // content is never NULL
-      GNUNET_assert (queue->content != NULL);
-      if (memcmp(target, &(queue->content->target),
-          sizeof(struct GNUNET_PeerIdentity)) == 0)
+      queue = endpoint->sessions_head;
+      endpoint_next = endpoint->next;
+      while (queue != NULL)
         {
-          //session found
-          //is this session pending for send
-          while (pendingsession != NULL)
-            {
-              if (pendingsession->content == queue->content)
-                {
-                  plugin->pendingsessions--;
-                  GNUNET_CONTAINER_DLL_remove (plugin->pending_Sessions,
-                      plugin->pending_Sessions_tail, pendingsession);
-                  GNUNET_free(pendingsession);
-                  break;
-                }
-              pendingsession = pendingsession->next;
-            }
-
-          //is something of this session in the fragment queue?
-          fm = get_fragment_message_from_session(queue->content);
-          free_fragment_message(plugin, fm);
-
-          //dispose all received fragments
-          free_rec_frag_queue(queue->content);
-
-          // remove PendingMessage
-          pm = queue->content->pending_message;
-          if (pm != NULL)
+          // content is never NULL
+          GNUNET_assert (queue->content != NULL);
+          queue_next = queue->next;
+          if (memcmp(target, &(queue->content->target),
+              sizeof(struct GNUNET_PeerIdentity)) == 0)
             {
-              GNUNET_free_non_null(pm->msg);
-              GNUNET_free(pm);
+              free_session(plugin, queue, GNUNET_YES);
             }
-
-          GNUNET_free(queue->content);
-          GNUNET_CONTAINER_DLL_remove(plugin->sessions, plugin->sessions_tail, queue);
-          GNUNET_free(queue);
-          plugin->session_count--;
-
-          return;
+          // try next
+          queue = queue_next;
         }
-      // try next
-      queue = queue->next;
+      endpoint = endpoint_next;
     }
 }
 
@@ -1771,260 +1973,17 @@ wlan_plugin_address_pretty_printer(void *cls, const char *type,
   //GNUNET_assert(cls !=NULL);
   if (addrlen != 6)
     {
-      /* invalid address (MAC addresses have 6 bytes) */
-      GNUNET_break (0);
+      /* invalid address (MAC addresses have 6 bytes) */GNUNET_break (0);
       asc(asc_cls, NULL);
       return;
     }
   input = (const unsigned char*) addr;
-  GNUNET_snprintf(ret, sizeof(ret), "%s Mac-Address %.2X:%.2X:%.2X:%.2X:%.2X:%.2X",
-      PROTOCOL_PREFIX, input[0], input[1], input[2], input[3], input[4],
-      input[5]);
+  GNUNET_snprintf(ret, sizeof(ret),
+      "%s Mac-Address %.2X:%.2X:%.2X:%.2X:%.2X:%.2X", PROTOCOL_PREFIX,
+      input[0], input[1], input[2], input[3], input[4], input[5]);
   asc(asc_cls, ret);
 }
 
-/**
- * Another peer has suggested an address for this
- * peer and transport plugin.  Check that this could be a valid
- * address.  If so, consider adding it to the list
- * of addresses.
- *
- * @param cls closure
- * @param addr pointer to the address
- * @param addrlen length of addr
- * @return GNUNET_OK if this is a plausible address for this peer
- *         and transport
- */
-
-static int
-wlan_plugin_address_suggested(void *cls, const void *addr, size_t addrlen)
-{
-  //struct Plugin *plugin = cls;
-
-  /* check if the address is plausible; if so,
-   add it to our list! */
-
-  GNUNET_assert(cls !=NULL);
-  //FIXME mitm is not checked
-  //Mac Address has 6 bytes
-  if (addrlen == 6)
-    {
-      /* TODO check for bad addresses like multicast, broadcast, etc */
-      return GNUNET_OK;
-    }
-  else
-    {
-      return GNUNET_SYSERR;
-    }
-
-  return GNUNET_SYSERR;
-}
-
-/**
- * Function called for a quick conversion of the binary address to
- * a numeric address.  Note that the caller must not free the 
- * address and that the next call to this function is allowed
- * to override the address again.
- *
- * @param cls closure
- * @param addr binary address
- * @param addrlen length of the address
- * @return string representing the same address 
- */
-static const char*
-wlan_plugin_address_to_string(void *cls, const void *addr, size_t addrlen)
-{
-  static char ret[40];
-  const unsigned char * input;
-
-  //GNUNET_assert(cls !=NULL);
-  if (addrlen != 6)
-    {
-      /* invalid address (MAC addresses have 6 bytes) */
-      GNUNET_break (0);
-      return NULL;
-    }
-  input = (const unsigned char*) addr;
-  GNUNET_snprintf(ret, sizeof(ret), "%s Mac-Address %.2X:%.2X:%.2X:%.2X:%.2X:%.2X",
-      PROTOCOL_PREFIX, input[0], input[1], input[2], input[3], input[4],
-      input[5]);
-  return ret;
-}
-
-/**
- * Function to test if fragment number already exists in the fragments received
- *
- * @param session session the fragment belongs to
- * @param fh Fragmentheader of the fragment
- * @return GNUNET_YES if fragment exists already, GNUNET_NO if it does not exists in the queue of the session
- */
-
-static const int
-is_double_msg(struct Session * session, struct FragmentationHeader * fh)
-{
-  struct RecQueue * rec_queue = session->frag_head;
-  while (rec_queue != NULL)
-    {
-      if (rec_queue->num == fh->fragment_off_or_num)
-        {
-          return GNUNET_YES;
-        }
-      rec_queue = rec_queue->next;
-
-    }
-  return GNUNET_NO;
-}
-
-/**
- * Function to insert a fragment in a queue of a session
- * @param session session the fragment belongs to
- * @param rec_queue fragment to add
- */
-
-static void
-insert_fragment_in_queue(struct Session * session, struct RecQueue * rec_queue)
-{
-  struct RecQueue * rec_queue2 = session->frag_head;
-  struct WlanHeader * wlanheader = NULL;
-  //first received fragment of message
-  if (session->rec_size == NO_MESSAGE_OR_MESSAGE_FINISHED)
-    {
-      session->rec_size = MESSAGE_LENGHT_UNKNOWN;
-    }
-  //this is the first fragment of the message (fragment id 0)
-  if (rec_queue->num == 0)
-    {
-      wlanheader = (struct WlanHeader *) rec_queue->msg;
-      session->rec_size = ntohs(wlanheader->header.size);
-    }
-
-  //sort into list
-  while (rec_queue2 != NULL)
-    {
-      if (rec_queue2->num > rec_queue->num)
-        {
-          //next element number is grater than the current num
-          GNUNET_CONTAINER_DLL_insert_before(session->frag_head, session->frag_tail, rec_queue2, rec_queue);
-          return;
-        }
-      rec_queue = rec_queue->next;
-    }
-  //no element has a grater number
-  GNUNET_CONTAINER_DLL_insert_tail(session->frag_head, session->frag_tail, rec_queue);
-}
-
-/**
- * Function to dispose the fragments received for a message
- * @param session session to free the fragments from
- */
-
-static void
-free_rec_frag_queue(struct Session * session)
-{
-  struct RecQueue * rec_queue = session->frag_head;
-  struct RecQueue * rec_queue2;
-  while (rec_queue != NULL)
-    {
-      rec_queue2 = rec_queue;
-      rec_queue = rec_queue->next;
-      GNUNET_free(rec_queue2);
-    }
-  session->frag_head = NULL;
-  session->frag_tail = NULL;
-  session->rec_size = NO_MESSAGE_OR_MESSAGE_FINISHED;
-}
-
-/**
- * Function to check if all fragments of a message have been received
- * @param plugin the plugin handle
- * @param session_light information of the message sender
- * @param session session the message belongs to
- */
-
-static void
-check_rec_finished_msg(struct Plugin* plugin,
-    struct Session_light * session_light, struct Session * session)
-{
-  struct RecQueue * rec_queue = session->frag_head;
-  int packetsize = session->rec_size;
-  int sum = 0;
-  int aktnum = 0;
-  char * msg;
-  //some fragment should be received
-  GNUNET_assert(session->rec_size != NO_MESSAGE_OR_MESSAGE_FINISHED);
-  //check if first fragment is present
-  if (session->rec_size == MESSAGE_LENGHT_UNKNOWN)
-    {
-      return;
-    }
-  while (rec_queue != NULL)
-    {
-      sum += rec_queue->size;
-      //check if all fragment numbers are present
-      if (rec_queue->num != aktnum)
-        {
-          return;
-        }
-      aktnum++;
-      rec_queue = rec_queue->next;
-    }
-  //sum should always be smaller or equal of
-  GNUNET_assert(sum <= packetsize);
-  if (sum == packetsize)
-    {
-
-#if DEBUG_wlan
-      GNUNET_log(GNUNET_ERROR_TYPE_DEBUG,
-          "check_rec_finished_msg: A message for %p is complete\n", session);
-#endif
-
-      //copy fragments together
-      msg = GNUNET_malloc(packetsize);
-      rec_queue = session->frag_head;
-      aktnum = 0;
-      while (rec_queue != NULL)
-        {
-          //TODO SAVE SOME COPY OPS AND CHECK CRC WITHOUT COPY
-          memcpy(msg + aktnum, rec_queue->msg, rec_queue->size);
-          aktnum += rec_queue->size;
-          rec_queue = rec_queue->next;
-        }
-      free_rec_frag_queue(session);
-      //call wlan_process_helper to process the message
-      wlan_data_massage_handler(plugin, session_light,
-          (struct GNUNET_MessageHeader*) msg);
-      //wlan_data_helper (plugin, session_light, (struct GNUNET_MessageHeader*) msg);
-
-      GNUNET_free(msg);
-    }
-}
-
-static void
-process_data(void *cls, void *client,
-    const struct GNUNET_MessageHeader *hdr){
-
-  GNUNET_assert(client != NULL);
-  GNUNET_assert(cls != NULL);
-  struct Session * session = (struct Session * )client;
-  struct Plugin * plugin = (struct Plugin * ) cls;
-
-  struct GNUNET_TRANSPORT_ATS_Information distance[2];
-  distance[0].type = htonl(GNUNET_TRANSPORT_ATS_QUALITY_NET_DISTANCE);
-  distance[0].value = htonl(1);
-  distance[1].type = htonl(GNUNET_TRANSPORT_ATS_ARRAY_TERMINATOR);
-  distance[1].value = htonl(0);
-
-#if DEBUG_wlan
-      GNUNET_log(GNUNET_ERROR_TYPE_DEBUG,
-          "Calling plugin->env->receive for session %p; %s\n", session,
-          wlan_plugin_address_to_string(NULL, session->addr, 6));
-#endif
-
-  plugin->env->receive(plugin->env->cls, &(session->target), hdr,
-      (const struct GNUNET_TRANSPORT_ATS_Information *) &distance, 2,
-      session, session->addr, sizeof(session->addr));
-}
-
 /**
  * handels the data after all fragments are put together
  * @param plugin
@@ -2032,15 +1991,16 @@ process_data(void *cls, void *client,
  * @param hdr pointer to the data
  */
 static void
-wlan_data_massage_handler(struct Plugin * plugin,
-    struct Session_light * session_light,
-    const struct GNUNET_MessageHeader * hdr)
+wlan_data_message_handler(void *cls, const struct GNUNET_MessageHeader *hdr)
 {
-  struct WlanHeader * wlanheader = NULL;
-  struct Session * session = NULL;
-  const char * tempmsg = NULL;
-  const struct GNUNET_MessageHeader * temp_hdr = NULL;
-  struct GNUNET_PeerIdentity tmptarget;
+  struct MacEndpoint * endpoint = (struct MacEndpoint *) cls;
+  struct Plugin * plugin = endpoint->plugin;
+  struct WlanHeader * wlanheader;
+  struct Session * session;
+  //const char * tempmsg;
+  const struct GNUNET_MessageHeader * temp_hdr;
+  struct GNUNET_PeerIdentity tmpsource;
+  int crc;
 
   if (ntohs(hdr->type) == GNUNET_MESSAGE_TYPE_WLAN_DATA)
     {
@@ -2048,26 +2008,33 @@ wlan_data_massage_handler(struct Plugin * plugin,
 #if DEBUG_wlan
       GNUNET_log(
           GNUNET_ERROR_TYPE_DEBUG,
-          "Func wlan_data_massage_handler got GNUNET_MESSAGE_TYPE_WLAN_DATA size: %u\n",
+          "Func wlan_data_message_handler got GNUNET_MESSAGE_TYPE_WLAN_DATA size: %u\n",
           ntohs(hdr->size));
 #endif
 
-      GNUNET_assert(session_light != NULL);
-      if (session_light->session == NULL)
+      if (ntohs(hdr->size) < sizeof(struct WlanHeader)
+          + sizeof(struct GNUNET_MessageHeader))
         {
-          session_light->session = search_session(plugin, session_light->addr);
+          //packet not big enought
+          return;
         }
-      session = session_light->session;
+
       wlanheader = (struct WlanHeader *) hdr;
-      tempmsg = (char*) &wlanheader[1];
-      temp_hdr = (const struct GNUNET_MessageHeader *) &wlanheader[1];
 
-      if (getcrc32(tempmsg, ntohs(wlanheader->header.size)) != ntohl(
-          wlanheader->crc))
+      session = search_session(plugin, endpoint, &wlanheader->source);
+
+      //tempmsg = (char*) &wlanheader[1];
+      temp_hdr = (const struct GNUNET_MessageHeader *) &wlanheader[1];
+      crc = ntohl(wlanheader->crc);
+      wlanheader->crc = 0;
+      if (getcrc32((char *) wlanheader, ntohs(wlanheader->header.size)) != crc)
         {
           //wrong crc, dispose message
           GNUNET_log(GNUNET_ERROR_TYPE_INFO,
-              "Wlan message Header crc was wrong\n");
+              "Wlan message header crc was wrong: %u != %u\n",
+              getcrc32((char *) wlanheader, ntohs(wlanheader->header.size)),
+              crc);
+          hexdump((void *) hdr, ntohs(hdr->size));
           return;
         }
 
@@ -2089,17 +2056,14 @@ wlan_data_massage_handler(struct Plugin * plugin,
                 {
                   if (GNUNET_HELLO_get_id(
                       (const struct GNUNET_HELLO_Message *) temp_hdr,
-                      &tmptarget) == GNUNET_OK)
+                      &tmpsource) == GNUNET_OK)
                     {
-                      session = create_session(plugin, session_light->addr);
-                      session_light->session = session;
-                      memcpy(&session->target, &tmptarget,
-                          sizeof(struct GNUNET_PeerIdentity));
+                      session = create_session(plugin, endpoint, &tmpsource);
                     }
                   else
                     {
                       GNUNET_log(GNUNET_ERROR_TYPE_WARNING,
-                          "WLAN client not in session list and hello message not okay\n");
+                          "WLAN client not in session list and hello message is not okay\n");
                       return;
                     }
 
@@ -2124,46 +2088,71 @@ wlan_data_massage_handler(struct Plugin * plugin,
 
       //"receive" the message
 
+      if (memcmp(&wlanheader->source, &session->target,
+          sizeof(struct GNUNET_PeerIdentity)) != 0)
+        {
+          //wrong peer id
+#if DEBUG_wlan
+          GNUNET_log(
+              GNUNET_ERROR_TYPE_DEBUG,
+              "WLAN peer source id doesn't match packet peer source id: session %p\n",
+              session);
+#endif
+          return;
+        }
 
-      GNUNET_SERVER_mst_receive(plugin->data_tokenizer, session, (const char *) temp_hdr,
-          ntohs(hdr->size) - sizeof(struct WlanHeader), GNUNET_YES, GNUNET_NO);
+      if (memcmp(&wlanheader->target, plugin->env->my_identity,
+          sizeof(struct GNUNET_PeerIdentity)) != 0)
+        {
+          //wrong peer id
+#if DEBUG_wlan
+          GNUNET_log(GNUNET_ERROR_TYPE_DEBUG,
+              "WLAN peer target id doesn't match our peer id: session %p\n",
+              session);
+#endif
+          return;
+        }
 
+      GNUNET_SERVER_mst_receive(plugin->data_tokenizer, session,
+          (const char *) temp_hdr,
+          ntohs(hdr->size) - sizeof(struct WlanHeader), GNUNET_YES, GNUNET_NO);
 
       return;
     }
   else
     {
       GNUNET_log(GNUNET_ERROR_TYPE_WARNING,
-          "wlan_data_massage_handler got wrong message type\n");
+          "wlan_data_message_handler got wrong message type\n");
       return;
     }
 }
 
-/**
- * function to add an ack to send it for a received fragment
- * @param plugin pointer to the global plugin structure
- * @param session pointer to the session this ack belongs to
- * @param fh pointer to the fragmentation header which we would like to acknolage
- */
-
-void
-add_ack_for_send(struct Plugin * plugin, struct Session * session,
-    struct FragmentationHeader * fh)
+//TODO DOXIGEN
+static void
+process_data(void *cls, void *client, const struct GNUNET_MessageHeader *hdr)
 {
-  struct AckSendQueue * ack;
 
-  GNUNET_assert(plugin != NULL);
-  GNUNET_assert(session != NULL);
-  GNUNET_assert(fh != NULL);
+  GNUNET_assert(client != NULL);
+  GNUNET_assert(cls != NULL);
+  struct Session * session = (struct Session *) client;
+  struct Plugin * plugin = (struct Plugin *) cls;
 
-  ack = GNUNET_malloc(sizeof(struct AckSendQueue));
-  ack->fragment_off_or_num = ntohs(fh->fragment_off_or_num);
-  ack->message_id = ntohl(fh->message_id);
-  ack->session = session;
+  struct GNUNET_TRANSPORT_ATS_Information distance[2];
+  distance[0].type = htonl(GNUNET_TRANSPORT_ATS_QUALITY_NET_DISTANCE);
+  distance[0].value = htonl(1);
+  distance[1].type = htonl(GNUNET_TRANSPORT_ATS_ARRAY_TERMINATOR);
+  distance[1].value = htonl(0);
 
-  GNUNET_CONTAINER_DLL_insert_tail(plugin->ack_send_queue_head,
-      plugin->ack_send_queue_tail, ack);
+#if DEBUG_wlan
+  GNUNET_log(GNUNET_ERROR_TYPE_DEBUG,
+      "Calling plugin->env->receive for session %p; %s; size: %u\n", session,
+      wlan_plugin_address_to_string(NULL, session->mac->addr.mac, 6),
+      htons(hdr->size));
+#endif
 
+  plugin->env->receive(plugin->env->cls, &(session->target), hdr,
+      (const struct GNUNET_TRANSPORT_ATS_Information *) &distance, 2, session,
+      (const char*) &session->mac->addr, sizeof(session->mac->addr));
 }
 
 /**
@@ -2175,20 +2164,12 @@ add_ack_for_send(struct Plugin * plugin, struct Session * session,
  */
 static void
 wlan_data_helper(void *cls, struct Session_light * session_light,
-    const struct GNUNET_MessageHeader * hdr)
+    const struct GNUNET_MessageHeader * hdr, const struct Radiotap_rx * rxinfo)
 {
   struct Plugin *plugin = cls;
-  struct Session * session = NULL;
-
-  struct FragmentationHeader * fh = NULL;
-  struct FragmentMessage * fm = NULL;
-
-  const char * tempmsg = NULL;
-
-  struct AckQueue * ack = NULL;
-  struct AckQueue * ack2 = NULL;
+  struct FragmentMessage * fm;
+  struct FragmentMessage * fm2;
 
-  struct RecQueue * rec_queue = NULL;
   //ADVERTISEMENT
   if (ntohs(hdr->type) == GNUNET_MESSAGE_TYPE_WLAN_ADVERTISEMENT)
     {
@@ -2201,12 +2182,14 @@ wlan_data_helper(void *cls, struct Session_light * session_light,
       GNUNET_log(
           GNUNET_ERROR_TYPE_DEBUG,
           "Func wlan_data_helper got GNUNET_MESSAGE_TYPE_WLAN_ADVERTISEMENT size: %u; %s\n",
-          ntohs(hdr->size), wlan_plugin_address_to_string(NULL,session_light->addr, 6));
+          ntohs(hdr->size),
+          wlan_plugin_address_to_string(NULL, session_light->addr.mac, 6));
 #endif
 
-      if (session_light->session == NULL)
+      if (session_light->macendpoint == NULL)
         {
-          session_light->session = get_Session(plugin, session_light->addr);
+          session_light->macendpoint = get_macendpoint(plugin,
+              &session_light->addr, GNUNET_NO);
         }
       GNUNET_assert(GNUNET_HELLO_get_id(
               (const struct GNUNET_HELLO_Message *) &hdr[1],
@@ -2215,187 +2198,116 @@ wlan_data_helper(void *cls, struct Session_light * session_light,
     }
 
   //FRAGMENT
-  else if (ntohs(hdr->type) == GNUNET_MESSAGE_TYPE_WLAN_FRAGMENT)
+
+  else if (ntohs(hdr->type) == GNUNET_MESSAGE_TYPE_FRAGMENT)
     {
 
       GNUNET_assert(session_light != NULL);
-      if (session_light->session == NULL)
+      if (session_light->macendpoint == NULL)
         {
-          session_light->session = search_session(plugin, session_light->addr);
+          session_light->macendpoint = get_macendpoint(plugin,
+              &session_light->addr, GNUNET_YES);
         }
-      session = session_light->session;
-
-      fh = (struct FragmentationHeader *) hdr;
-      tempmsg = (char*) &fh[1];
 
 #if DEBUG_wlan
       GNUNET_log(
           GNUNET_ERROR_TYPE_DEBUG,
-          "Func wlan_data_helper got GNUNET_MESSAGE_TYPE_WLAN_FRAGMENT with message_id %u with fragment number %i, size: %u; %s\n",
-          ntohl(fh->message_id), ntohs(fh->fragment_off_or_num), ntohs(
-              hdr->size), wlan_plugin_address_to_string(NULL,session_light->addr, 6));
+          "Func wlan_data_helper got GNUNET_MESSAGE_TYPE_FRAGMENT with size: %u; mac endpoint %p: %s\n",
+          ntohs(hdr->size), session_light->macendpoint,
+          wlan_plugin_address_to_string(NULL, session_light->addr.mac, 6));
 #endif
 
-      if (getcrc16(tempmsg, ntohs(fh->header.size)) != ntohs(fh->message_crc))
-        {
-          //wrong crc, dispose message
-          GNUNET_log(GNUNET_ERROR_TYPE_INFO, "WLAN fragment crc was wrong\n");
-          return;
-        }
-
-      //if in the session list
-      if (session != NULL)
+      int ret = GNUNET_DEFRAGMENT_process_fragment(
+          session_light->macendpoint->defrag, hdr);
+      if (ret == GNUNET_NO)
         {
-          //TODO fragments do not timeout
-          //check if message_id is right or it is a new msg
-          if ((session->message_id_in == ntohs(fh->message_id))
-              || (session->rec_size == NO_MESSAGE_OR_MESSAGE_FINISHED))
-            {
-              session->message_id_in = ntohs(fh->message_id);
-              if (is_double_msg(session, fh) != GNUNET_YES)
-                {
-                  //report size
-                  //TODO ask if it is right like this
-                  if (plugin->env->traffic_report != NULL)
-                    {
-                      plugin->env->traffic_report(plugin->env->cls,
-                          &session->target, ntohs(fh->header.size));
-                    }
-                  rec_queue
-                      = GNUNET_malloc(sizeof (struct RecQueue) +
-                          ntohs(fh->header.size) - sizeof(struct FragmentationHeader));
-                  rec_queue->size = ntohs(fh->header.size)
-                      - sizeof(struct FragmentationHeader);
-                  rec_queue->num = ntohs(fh->fragment_off_or_num);
-                  rec_queue->msg = (char*) &rec_queue[1];
-                  //copy msg to buffer
-                  memcpy((char *) rec_queue->msg, tempmsg, rec_queue->size);
-                  insert_fragment_in_queue(session, rec_queue);
-                  check_rec_finished_msg(plugin, session_light, session);
-                }
-              else
-                {
-                  GNUNET_log(GNUNET_ERROR_TYPE_INFO,
-                      "WLAN fragment is a clone\n");
-
-                }
-            }
-          else
-            {
-              GNUNET_log(
-                  GNUNET_ERROR_TYPE_INFO,
-                  "WLAN fragment message_id and session message_id are not the same and a message is already (partly) received\n");
-
-            }
+          session_light->macendpoint->dups++;
         }
-      else
+      else if (ret == GNUNET_OK)
         {
-          GNUNET_log(GNUNET_ERROR_TYPE_INFO,
-              "WLAN client not in session list\n");
-          wlan_data_massage_handler(plugin, session_light,
-              (struct GNUNET_MessageHeader *) tempmsg);
-          session = session_light->session;
-          //test if a session was created
-          if (session == NULL)
-            {
-              return;
-            }
+          session_light->macendpoint->fragc++;
         }
-
-      //TODO make and send ack
-      add_ack_for_send(plugin, session, fh);
-      check_next_fragment_timeout(plugin);
+      set_next_send(plugin);
 
     }
 
   //ACK
-  else if (ntohs(hdr->type) == GNUNET_MESSAGE_TYPE_WLAN_FRAGMENT_ACK)
+
+  else if (ntohs(hdr->type) == GNUNET_MESSAGE_TYPE_FRAGMENT_ACK)
     {
+      GNUNET_assert(session_light != NULL);
+      if (session_light->macendpoint == NULL)
+        {
+          session_light->macendpoint = get_macendpoint(plugin,
+              &session_light->addr, GNUNET_NO);
+        }
+
+      if (session_light->macendpoint == NULL)
+        {
+#if DEBUG_wlan
+          GNUNET_log(
+              GNUNET_ERROR_TYPE_DEBUG,
+              "Macendpoint does not exist for this GNUNET_MESSAGE_TYPE_FRAGMENT_ACK size: %u; %s\n",
+              ntohs(hdr->size),
+              wlan_plugin_address_to_string(NULL, session_light->addr.mac, 6));
+#endif
+          return;
+        }
 
 #if DEBUG_wlan
       GNUNET_log(
           GNUNET_ERROR_TYPE_DEBUG,
-          "Func wlan_data_helper got GNUNET_MESSAGE_TYPE_WLAN_FRAGMENT_ACK size: %u; %s\n",
-          ntohs(hdr->size), wlan_plugin_address_to_string(NULL,session_light->addr, 6));
+          "Func wlan_data_helper got GNUNET_MESSAGE_TYPE_FRAGMENT_ACK size: %u; mac endpoint: %p; %s\n",
+          ntohs(hdr->size), session_light->macendpoint,
+          wlan_plugin_address_to_string(NULL, session_light->addr.mac, 6));
 #endif
-
-      GNUNET_assert(session_light != NULL);
-      if (session_light->session == NULL)
-        {
-          session_light->session = search_session(plugin, session_light->addr);
-          GNUNET_assert(session_light->session != NULL);
-        }
-      session = session_light->session;
-      fh = (struct FragmentationHeader *) hdr;
-      if (session->message_id_out == ntohl(fh->message_id))
+      fm = session_light->macendpoint->sending_messages_head;
+      while (fm != NULL)
         {
-          fm = get_fragment_message_from_session(session);
-          if (fm != NULL)
+          fm2 = fm->next;
+          int ret = GNUNET_FRAGMENT_process_ack(fm->fragcontext, hdr);
+          if (ret == GNUNET_OK)
             {
-
-              ack2 = fm->head;
-              while (ack2 != NULL)
-                {
-                  // check for double
-                  if (ack2->fragment_num != ntohs(fh->fragment_off_or_num))
-                    {
-                      // check if next ack has bigger number
-                      if (ack2->fragment_num > ntohs(fh->fragment_off_or_num))
-                        {
-                          ack = GNUNET_malloc(sizeof(struct AckQueue));
-                          ack->fragment_num = ntohs(fh->fragment_off_or_num);
-                          GNUNET_CONTAINER_DLL_insert_before(fm->head,fm->tail,ack2,ack);
-                          //check if finished
-                          check_finished_fragment(plugin, fm);
-                          return;
-                        }
-                    }
-                  else
-                    {
-                      //double ack
-#if DEBUG_wlan
-                      GNUNET_log(
-                          GNUNET_ERROR_TYPE_DEBUG,
-                          "WLAN got double ack for message id %u and fragment num %u\n",
-                          session->message_id_out, ack2->fragment_num);
+#if DEBUG_wlan_retransmission
+              GNUNET_log(GNUNET_ERROR_TYPE_DEBUG,
+                  "Got last ack, finished fragment message %p\n", fm);
 #endif
-                      return;
-                    }
-                  ack2 = ack2->next;
-                }
-
-              //all acks are have smaller numbers
-              ack = GNUNET_malloc(sizeof(struct AckQueue));
-              ack->fragment_num = ntohs(fh->fragment_off_or_num);
-              GNUNET_CONTAINER_DLL_insert_tail(fm->head,fm->tail,ack);
-              check_finished_fragment(plugin, fm);
+              session_light->macendpoint->acks++;
+              free_fragment_message(plugin, fm);
+              check_fragment_queue(plugin);
+              return;
             }
-          else
+          if (ret == GNUNET_NO)
             {
-              GNUNET_log(
-                  GNUNET_ERROR_TYPE_WARNING,
-                  "WLAN fragment not in fragment list but id %u of ack is right\n",
-                  ntohl(fh->message_id));
+#if DEBUG_wlan_retransmission
+              GNUNET_log(GNUNET_ERROR_TYPE_DEBUG, "Got ack for: %p\n", fm);
+#endif
+              session_light->macendpoint->acks++;
               return;
             }
+          if (ret == GNUNET_SYSERR)
+            {
+
+            }
 
+          fm = fm2;
         }
-      else
-        {
-#if DEBUG_wlan
-          GNUNET_log(
-              GNUNET_ERROR_TYPE_DEBUG,
-              _("WLAN got ack but session->message_id_out %u and fragment id %u mismatch\n"),
-              session->message_id_out, ntohl(fh->message_id));
+
+#if DEBUG_wlan_retransmission
+      GNUNET_log(GNUNET_ERROR_TYPE_DEBUG,
+          "WLAN fragment not in fragment list\n");
 #endif
-        }
+      return;
 
     }
   else
     {
       // TODO Wrong data?
-      GNUNET_log(GNUNET_ERROR_TYPE_INFO,
-          "WLAN packet inside the WLAN helper packet has not the right type\n");
+      GNUNET_log(
+          GNUNET_ERROR_TYPE_INFO,
+          "WLAN packet inside the WLAN helper packet has not the right type: %u size: %u\n",
+          ntohs(hdr->type), ntohs(hdr->size));
+      GNUNET_break(0);
       return;
     }
 
@@ -2406,6 +2318,44 @@ wlan_data_helper(void *cls, struct Session_light * session_light,
 
 }
 
+//TODO DOXIGEN
+const char *
+macprinter(const u_int8_t * mac)
+{
+  static char macstr[20];
+
+  GNUNET_snprintf(macstr, sizeof(macstr), "%X:%X:%X:%X:%X:%X", mac[0], mac[1],
+      mac[2], mac[3], mac[4], mac[5]);
+  return macstr;
+}
+
+/**
+ * function to create an macendpoint
+ * @param plugin pointer to the plugin struct
+ * @param addr pointer to the macaddress
+ * @return returns a macendpoint
+ */
+static struct MacEndpoint *
+create_macendpoint(struct Plugin *plugin, const struct MacAddress *addr)
+{
+  struct MacEndpoint * newend = GNUNET_malloc(sizeof (struct MacEndpoint));
+  newend->addr = *addr;
+  newend->plugin = plugin;
+  newend->addr = *addr;
+  newend->fragment_messages_out_count = 0;
+  newend->defrag = GNUNET_DEFRAGMENT_context_create(plugin->env->stats,
+      WLAN_MTU, MESSAGES_IN_DEFRAG_QUEUE_PER_MAC, newend,
+      &wlan_data_message_handler, &add_ack_for_send);
+
+  plugin->mac_count++;
+  GNUNET_CONTAINER_DLL_insert_tail(plugin->mac_head, plugin->mac_tail, newend);
+#if DEBUG_wlan
+  GNUNET_log(GNUNET_ERROR_TYPE_DEBUG, "New Mac Endpoint %p: %s\n", newend,
+      wlan_plugin_address_to_string(NULL, newend->addr.mac, 6));
+#endif
+  return newend;
+}
+
 /**
  * Function used for to process the data from the suid process
  *
@@ -2413,131 +2363,128 @@ wlan_data_helper(void *cls, struct Session_light * session_light,
  * @param client client that send the data (not used)
  * @param hdr header of the GNUNET_MessageHeader
  */
-
 static void
 wlan_process_helper(void *cls, void *client,
     const struct GNUNET_MessageHeader *hdr)
 {
   struct Plugin *plugin = cls;
-  struct IeeeHeader * wlanIeeeHeader = NULL;
+  struct ieee80211_frame * wlanIeeeHeader = NULL;
   struct Session_light * session_light = NULL;
+  struct Radiotap_rx * rxinfo;
   const struct GNUNET_MessageHeader * temp_hdr = NULL;
 
   int datasize = 0;
-  int pos = 0;
+  int pos;
 
-  if (ntohs(hdr->type) == GNUNET_MESSAGE_TYPE_WLAN_HELPER_DATA)
+  switch (ntohs(hdr->type))
     {
+  case GNUNET_MESSAGE_TYPE_WLAN_HELPER_DATA:
 #if DEBUG_wlan
-      GNUNET_log(
-          GNUNET_ERROR_TYPE_DEBUG,
-          "Func wlan_process_helper got  GNUNET_MESSAGE_TYPE_WLAN_HELPER_DATA size: %u\n",
-          ntohs(hdr->size));
+    GNUNET_log(
+        GNUNET_ERROR_TYPE_DEBUG,
+        "Func wlan_process_helper got  GNUNET_MESSAGE_TYPE_WLAN_HELPER_DATA size: %u\n",
+        ntohs(hdr->size));
 #endif
 
-      //call wlan_process_helper with the message inside, later with wlan: analyze signal
-      GNUNET_assert(ntohs(hdr->size) >= sizeof(struct IeeeHeader) + sizeof(struct GNUNET_MessageHeader));
-      wlanIeeeHeader = (struct IeeeHeader *) &hdr[1];
-
-      //process only if it is an broadcast or for this computer both with the gnunet bssid
-
-      //check for bssid
-      if (memcmp(&(wlanIeeeHeader->mac2), macbc, sizeof(struct MacAddress))
-          == 0)
-        {
-          //check for broadcast or mac
-          if (memcmp(&(wlanIeeeHeader->mac1), bc_all_mac,
-              sizeof(struct MacAddress) == 0) || memcmp(
-              &(wlanIeeeHeader->mac1), &(plugin->mac_address),
-              sizeof(struct MacAddress)) == 0)
-            {
-
-              // process the inner data
-
-
-              datasize = ntohs(hdr->size) - sizeof(struct IeeeHeader)
-                  - sizeof(struct GNUNET_MessageHeader);
-
-              session_light = GNUNET_malloc(sizeof(struct Session_light));
-              memcpy(session_light->addr, &(wlanIeeeHeader->mac3),
-                  sizeof(struct MacAddress));
-              //session_light->session = search_session(plugin,session_light->addr);
-
-              pos = 0;
-              temp_hdr = (struct GNUNET_MessageHeader *) &wlanIeeeHeader[1];
-              while (pos < datasize)
-                {
-                  temp_hdr = (struct GNUNET_MessageHeader *) &wlanIeeeHeader[1]
-                      + pos;
-
-                  wlan_data_helper(plugin, session_light, temp_hdr);
-                  pos += ntohs(temp_hdr->size);
-
-                }
-
-              //clean up
-              GNUNET_free(session_light);
-            }
-          else
-            {
+    //call wlan_process_helper with the message inside, later with wlan: analyze signal
+    if (ntohs(hdr->size) < sizeof(struct ieee80211_frame)
+        + sizeof(struct GNUNET_MessageHeader) + sizeof(struct Radiotap_rx))
+      {
 #if DEBUG_wlan
-              GNUNET_log(GNUNET_ERROR_TYPE_DEBUG,
-                  "Func wlan_process_helper got wrong MAC: %s\n",
-                  wlanIeeeHeader->mac1);
+        GNUNET_log(
+            GNUNET_ERROR_TYPE_DEBUG,
+            "Size of packet is too small; size: %u min size: %u\n",
+            ntohs(hdr->size),
+            sizeof(struct ieee80211_frame)
+                + sizeof(struct GNUNET_MessageHeader));
 #endif
-            }
-        }
-      else
-        {
+        //GNUNET_break (0);
+        /* FIXME: restart SUID process */
+        return;
+      }
+    rxinfo = (struct Radiotap_rx *) &hdr[1];
+    wlanIeeeHeader = (struct ieee80211_frame *) &rxinfo[1];
+
+    //process only if it is an broadcast or for this computer both with the gnunet bssid
+
+    //check for bssid
+    if (memcmp(&(wlanIeeeHeader->i_addr3), &mac_bssid,
+        sizeof(struct MacAddress)) == 0)
+      {
+        //check for broadcast or mac
+        if (memcmp(&(wlanIeeeHeader->i_addr1), &bc_all_mac,
+            sizeof(struct MacAddress) == 0) || memcmp(
+            &(wlanIeeeHeader->i_addr1), &(plugin->mac_address),
+            sizeof(struct MacAddress)) == 0)
+          {
+
+            // process the inner data
+
+
+            datasize = ntohs(hdr->size) - sizeof(struct ieee80211_frame)
+                - sizeof(struct GNUNET_MessageHeader)
+                - sizeof(struct Radiotap_rx);
+
+            session_light = GNUNET_malloc(sizeof(struct Session_light));
+            memcpy(&session_light->addr, &(wlanIeeeHeader->i_addr2),
+                sizeof(struct MacAddress));
+            //session_light->session = search_session(plugin,session_light->addr);
+
+            pos = 0;
+            while (pos < datasize)
+              {
+                temp_hdr = (struct GNUNET_MessageHeader *) &wlanIeeeHeader[1]
+                    + pos;
+
+                wlan_data_helper(plugin, session_light, temp_hdr, rxinfo);
+                pos += ntohs(temp_hdr->size);
+
+              }
+
+            //clean up
+            GNUNET_free(session_light);
+          }
+        else
+          {
 #if DEBUG_wlan
-          GNUNET_log(GNUNET_ERROR_TYPE_DEBUG,
-              "Func wlan_process_helper got wrong BSSID: %s\n",
-              wlanIeeeHeader->mac2);
+            GNUNET_log(GNUNET_ERROR_TYPE_DEBUG,
+                "Func wlan_process_helper got wrong MAC: %s\n",
+                macprinter(wlanIeeeHeader->i_addr1));
 #endif
-        }
-
-
-
-    }
-
-  else if (ntohs(hdr->type) == GNUNET_MESSAGE_TYPE_WLAN_HELPER_CONTROL)
-    {
-
+          }
+      }
+    else
+      {
 #if DEBUG_wlan
-      GNUNET_log(
-          GNUNET_ERROR_TYPE_DEBUG,
-          "Func wlan_process_helper got  GNUNET_MESSAGE_TYPE_WLAN_HELPER_CONTROL size: %u\n",
-          ntohs(hdr->size));
+        GNUNET_log(GNUNET_ERROR_TYPE_DEBUG,
+            "Func wlan_process_helper got wrong BSSID: %s\n",
+            macprinter(wlanIeeeHeader->i_addr2));
 #endif
-
-      //TODO more control messages
-      //TODO use struct wlan_helper_control
-      if (ntohs(hdr->size) == sizeof(struct Wlan_Helper_Control_Message))
-        {
-          //plugin->mac_address = GNUNET_malloc(sizeof(struct MacAddress));
-          memcpy(&(plugin->mac_address), &hdr[1], sizeof(struct MacAddress));
-          GNUNET_log(GNUNET_ERROR_TYPE_DEBUG,
-              "Notifying transport of address %s\n",
-              wlan_plugin_address_to_string(cls, &(plugin->mac_address), ntohs(
-                  hdr->size) - sizeof(struct GNUNET_MessageHeader)));
-          plugin->env->notify_address(plugin->env->cls, "wlan",
-              &plugin->mac_address, sizeof(struct MacAddress),
-              GNUNET_TIME_UNIT_FOREVER_REL);
-        }
-      else
-        {
-          GNUNET_log(GNUNET_ERROR_TYPE_DEBUG, "Wrong wlan mac address %s\n",
-              plugin->mac_address);
-        }
-
-    }
-
-  else
-    {
-      // TODO Wrong data?
-      GNUNET_log(GNUNET_ERROR_TYPE_INFO,
-          "WLAN helper packet has not the right type\n");
-      return;
+      }
+    break;
+  case GNUNET_MESSAGE_TYPE_WLAN_HELPER_CONTROL:
+    //TODO more control messages
+    //TODO use struct wlan_helper_control
+    if (ntohs(hdr->size) != sizeof(struct Wlan_Helper_Control_Message))
+      {
+        GNUNET_break (0);
+        /* FIXME: restart SUID process */
+        return;
+      }
+    memcpy(&plugin->mac_address, &hdr[1], sizeof(struct MacAddress));
+#if DEBUG_wlan
+    GNUNET_log(
+        GNUNET_ERROR_TYPE_DEBUG,
+        "Received WLAN_HELPER_CONTROL message with transport of address %s\n",
+        wlan_plugin_address_to_string(cls, &plugin->mac_address,
+            sizeof(struct MacAddress)));
+#endif
+    plugin->env->notify_address(plugin->env->cls, GNUNET_YES,
+        &plugin->mac_address, sizeof(struct MacAddress));
+    break;
+  default:
+    GNUNET_break (0);
+    return;
     }
 }
 
@@ -2549,7 +2496,6 @@ wlan_process_helper(void *cls, void *client,
  * @param cls the plugin handle
  * @param tc the scheduling context
  */
-
 static void
 wlan_plugin_helper_read(void *cls,
     const struct GNUNET_SCHEDULER_TaskContext *tc)
@@ -2557,13 +2503,7 @@ wlan_plugin_helper_read(void *cls,
   struct Plugin *plugin = cls;
   plugin->server_read_task = GNUNET_SCHEDULER_NO_TASK;
 
-  /*
-   #if DEBUG_wlan
-   GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
-   "Start reading from STDIN\n");
-   #endif
-   */
-  if (tc->reason == GNUNET_SCHEDULER_REASON_SHUTDOWN)
+  if (0 != (tc->reason & GNUNET_SCHEDULER_REASON_SHUTDOWN))
     return;
 
   char mybuf[WLAN_MTU + sizeof(struct GNUNET_MessageHeader)];
@@ -2580,8 +2520,8 @@ wlan_plugin_helper_read(void *cls,
 #endif
       return;
     }
-  GNUNET_SERVER_mst_receive(plugin->suid_tokenizer, NULL, mybuf, bytes, GNUNET_NO,
-      GNUNET_NO);
+  GNUNET_SERVER_mst_receive(plugin->suid_tokenizer, NULL, mybuf, bytes,
+      GNUNET_NO, GNUNET_NO);
 
   GNUNET_assert(plugin->server_read_task == GNUNET_SCHEDULER_NO_TASK);
   plugin->server_read_task = GNUNET_SCHEDULER_add_read_file(
@@ -2599,7 +2539,8 @@ wlan_plugin_helper_read(void *cls,
 static int
 wlan_transport_start_wlan_helper(struct Plugin *plugin, int testmode)
 {
-  const char * filename = "gnunet-transport-wlan-helper";
+  const char * filenamehw = "gnunet-transport-wlan-helper";
+  const char * filenameloopback = "gnunet-transport-wlan-helper-dummy";
   plugin->server_stdout = GNUNET_DISK_pipe(GNUNET_YES, GNUNET_NO, GNUNET_YES);
   if (plugin->server_stdout == NULL)
     return GNUNET_SYSERR;
@@ -2608,16 +2549,43 @@ wlan_transport_start_wlan_helper(struct Plugin *plugin, int testmode)
   if (plugin->server_stdin == NULL)
     return GNUNET_SYSERR;
 
+  /* Start the server process */
+
+  if (testmode == 0)
+    {
+
 #if DEBUG_wlan
-  GNUNET_log(GNUNET_ERROR_TYPE_DEBUG,
-      "Starting gnunet-wlan-helper process cmd: %s %s %i\n", filename,
-      plugin->interface, testmode);
+      GNUNET_log(GNUNET_ERROR_TYPE_DEBUG,
+          "Starting gnunet-wlan-helper process cmd: %s %s %i\n", filenamehw,
+          plugin->interface, testmode);
+#endif
+
+      plugin->server_proc = GNUNET_OS_start_process(plugin->server_stdin,
+          plugin->server_stdout, filenamehw, filenamehw, plugin->interface,
+          NULL);
+    }
+  else if (testmode == 1)
+    {
+
+#if DEBUG_wlan
+      GNUNET_log(GNUNET_ERROR_TYPE_DEBUG,
+          "Starting gnunet-wlan-helper loopback 1 process cmd: %s %s %i\n",
+          filenameloopback, plugin->interface, testmode);
 #endif
-  /* Start the server process */
 
-  plugin->server_proc = GNUNET_OS_start_process(plugin->server_stdin,
-      plugin->server_stdout, filename, filename, plugin->interface, ((testmode
-          == 1) ? "1" : (testmode == 2) ? "2" : "0"), NULL);
+      plugin->server_proc = GNUNET_OS_start_process(plugin->server_stdin,
+          plugin->server_stdout, filenameloopback, filenameloopback, "1", NULL);
+    }
+  else if (testmode == 2)
+    {
+#if DEBUG_wlan
+      GNUNET_log(GNUNET_ERROR_TYPE_DEBUG,
+          "Starting gnunet-wlan-helper loopback 2 process cmd: %s %s %i\n",
+          filenameloopback, plugin->interface, testmode);
+#endif
+      plugin->server_proc = GNUNET_OS_start_process(plugin->server_stdin,
+          plugin->server_stdout, filenameloopback, filenameloopback, "2", NULL);
+    }
   if (plugin->server_proc == NULL)
     {
 #if DEBUG_wlan
@@ -2645,8 +2613,6 @@ wlan_transport_start_wlan_helper(struct Plugin *plugin, int testmode)
       "Adding server_read_task for the wlan-helper\n");
 #endif
 
-  sleep(2);
-
   plugin->server_read_task = GNUNET_SCHEDULER_add_read_file(
       GNUNET_TIME_UNIT_FOREVER_REL, plugin->server_stdout_handle,
       &wlan_plugin_helper_read, plugin);
@@ -2665,20 +2631,49 @@ libgnunet_plugin_transport_wlan_done(void *cls)
 {
   struct GNUNET_TRANSPORT_PluginFunctions *api = cls;
   struct Plugin *plugin = api->cls;
+  struct MacEndpoint * endpoint = plugin->mac_head;
+  struct MacEndpoint * endpoint_next;
 
 #if DEBUG_wlan
   GNUNET_log(GNUNET_ERROR_TYPE_DEBUG,
       "libgnunet_plugin_transport_wlan_done started\n");
 #endif
 
-  GNUNET_assert(cls !=NULL);
+  GNUNET_DISK_pipe_close(plugin->server_stdout);
+  GNUNET_DISK_pipe_close(plugin->server_stdin);
+  GNUNET_OS_process_kill(plugin->server_proc, 9);
+  GNUNET_OS_process_close(plugin->server_proc);
+
+  GNUNET_assert (cls !=NULL);
+  //free sessions
+  while (endpoint != NULL)
+    {
+      endpoint_next = endpoint->next;
+      free_macendpoint(plugin, endpoint);
+      endpoint = endpoint_next;
+
+    }
+  if (plugin->server_write_delay_task != GNUNET_SCHEDULER_NO_TASK)
+    {
+      GNUNET_SCHEDULER_cancel(plugin->server_write_delay_task);
+      plugin->server_write_delay_task = GNUNET_SCHEDULER_NO_TASK;
+    }
+  if (plugin->server_write_task != GNUNET_SCHEDULER_NO_TASK)
+    {
+      GNUNET_SCHEDULER_cancel(plugin->server_write_task);
+      plugin->server_write_task = GNUNET_SCHEDULER_NO_TASK;
+    }
+  if (plugin->server_read_task != GNUNET_SCHEDULER_NO_TASK)
+    {
+      GNUNET_SCHEDULER_cancel(plugin->server_read_task);
+      plugin->server_read_task = GNUNET_SCHEDULER_NO_TASK;
+    }
 
   if (plugin->suid_tokenizer != NULL)
     GNUNET_SERVER_mst_destroy(plugin->suid_tokenizer);
 
   if (plugin->data_tokenizer != NULL)
-      GNUNET_SERVER_mst_destroy(plugin->data_tokenizer);
-
+    GNUNET_SERVER_mst_destroy(plugin->data_tokenizer);
 
   GNUNET_free_non_null(plugin->interface);
   GNUNET_free (plugin);
@@ -2706,18 +2701,35 @@ libgnunet_plugin_transport_wlan_init(void *cls)
   plugin = GNUNET_malloc (sizeof (struct Plugin));
   plugin->env = env;
   plugin->pendingsessions = 0;
-  plugin->session_count = 0;
+  plugin->mac_count = 0;
   plugin->server_write_task = GNUNET_SCHEDULER_NO_TASK;
   plugin->server_read_task = GNUNET_SCHEDULER_NO_TASK;
   plugin->server_write_delay_task = GNUNET_SCHEDULER_NO_TASK;
+  GNUNET_BANDWIDTH_tracker_init(&plugin->tracker,
+      GNUNET_BANDWIDTH_value_init(100 * 1024 * 1024 / 8), 100);
 
-  set_next_beacon_time(plugin);
+  plugin->suid_tokenizer = GNUNET_SERVER_mst_create(&wlan_process_helper,
+      plugin);
+
+  plugin->data_tokenizer = GNUNET_SERVER_mst_create(&process_data, plugin);
+
+  //plugin->sessions = GNUNET_malloc (sizeof (struct Sessionqueue));
+  //plugin->pending_Sessions_head = GNUNET_malloc (sizeof (struct Sessionqueue));
+
+  api = GNUNET_malloc (sizeof (struct GNUNET_TRANSPORT_PluginFunctions));
+  api->cls = plugin;
+  api->send = &wlan_plugin_send;
+  api->disconnect = &wlan_plugin_disconnect;
+  api->address_pretty_printer = &wlan_plugin_address_pretty_printer;
+  api->check_address = &wlan_plugin_address_suggested;
+  api->address_to_string = &wlan_plugin_address_to_string;
+  //read config
 
   if (GNUNET_CONFIGURATION_have_value(env->cfg, "transport-wlan", "TESTMODE"))
     {
       if (GNUNET_SYSERR == GNUNET_CONFIGURATION_get_value_number(env->cfg,
           "transport-wlan", "TESTMODE", &testmode))
-        return NULL;
+        testmode = 0; //default value
     }
 
   if (GNUNET_CONFIGURATION_have_value(env->cfg, "transport-wlan", "INTERFACE"))
@@ -2725,28 +2737,15 @@ libgnunet_plugin_transport_wlan_init(void *cls)
       if (GNUNET_CONFIGURATION_get_value_string(env->cfg, "transport-wlan",
           "INTERFACE", &(plugin->interface)) != GNUNET_YES)
         {
-          libgnunet_plugin_transport_wlan_done(plugin);
+          libgnunet_plugin_transport_wlan_done(api);
           return NULL;
         }
     }
 
-  wlan_transport_start_wlan_helper(plugin, testmode);
-  plugin->suid_tokenizer = GNUNET_SERVER_mst_create(&wlan_process_helper, plugin);
-
-  plugin->data_tokenizer = GNUNET_SERVER_mst_create(&process_data, plugin);
-
-  //plugin->sessions = GNUNET_malloc (sizeof (struct Sessionqueue));
-  //plugin->pending_Sessions = GNUNET_malloc (sizeof (struct Sessionqueue));
-
-  api = GNUNET_malloc (sizeof (struct GNUNET_TRANSPORT_PluginFunctions));
-  api->cls = plugin;
-  api->send = &wlan_plugin_send;
-  api->disconnect = &wlan_plugin_disconnect;
-  api->address_pretty_printer = &wlan_plugin_address_pretty_printer;
-  api->check_address = &wlan_plugin_address_suggested;
-  api->address_to_string = &wlan_plugin_address_to_string;
+  //start the plugin
+  set_next_beacon_time(plugin);
 
-  start_next_message_id();
+  wlan_transport_start_wlan_helper(plugin, testmode);
 
 #if DEBUG_wlan
   GNUNET_log(GNUNET_ERROR_TYPE_DEBUG, "wlan init finished\n");