diff --git a/configure.ac b/configure.ac
index 7456617a..adcc44be 100644
--- a/configure.ac
+++ b/configure.ac
@@ -260,6 +260,7 @@ AC_LIBTOOL_WIN32_DLL
 AC_PROG_LIBTOOL
 
 WIN32=no
+MACH=no
 AC_CANONICAL_HOST
 case $host_os in
     *mingw*)
@@ -275,6 +276,9 @@ case $host_os in
         CPPFLAGS="$CPPFLAGS -I/usr/local/include"
         ADD_NACL_OBJECTS_TO_PKGCONFIG="no"
     ;;
+    darwin*)
+        MACH=yes
+    ;;
 esac
 AM_CONDITIONAL(WIN32, test "x$WIN32" = "xyes")
 
@@ -427,7 +431,7 @@ AC_C_BIGENDIAN
 # Checks for library functions.
 AC_FUNC_FORK
 AC_CHECK_FUNCS([gettimeofday memset socket strchr malloc])
-if test "x$WIN32" != "xyes"; then
+if (test "x$WIN32" != "xyes") && (test "x$MACH" != "xyes"); then
     AC_CHECK_LIB(rt, clock_gettime,
         [
             RT_LIBS="-lrt"
diff --git a/other/bootstrap_daemon/Makefile.inc b/other/bootstrap_daemon/Makefile.inc
index b75d935f..0bc02ef9 100644
--- a/other/bootstrap_daemon/Makefile.inc
+++ b/other/bootstrap_daemon/Makefile.inc
@@ -1,6 +1,6 @@
 if BUILD_DHT_BOOTSTRAP_DAEMON
 
-noinst_PROGRAMS += tox_bootstrap_daemon
+bin_PROGRAMS += tox_bootstrap_daemon
 
 tox_bootstrap_daemon_SOURCES = \
                         ../other/bootstrap_daemon/tox_bootstrap_daemon.c
@@ -24,4 +24,4 @@ endif
 EXTRA_DIST += \
     $(top_srcdir)/other/bootstrap_daemon/conf \
     $(top_srcdir)/other/bootstrap_daemon/tox_bootstrap_daemon.sh
-    
\ No newline at end of file
+    
diff --git a/toxav/msi.h b/toxav/msi.h
index 2d4929a6..54ae8faf 100755
--- a/toxav/msi.h
+++ b/toxav/msi.h
@@ -40,7 +40,7 @@ typedef void ( *MSICallback ) ( int32_t, void *arg );
  * @brief Call type identifier. Also used as rtp callback prefix.
  */
 typedef enum {
-    type_audio = 70,
+    type_audio = 192,
     type_video
 } MSICallType;
 
diff --git a/toxav/rtp.c b/toxav/rtp.c
index cdaabd3a..1a42f99e 100755
--- a/toxav/rtp.c
+++ b/toxav/rtp.c
@@ -500,7 +500,7 @@ RTPMessage *msg_parse ( uint16_t sequnum, const uint8_t *data, int length )
  * @retval -1 Error occurred.
  * @retval 0 Success.
  */
-int rtp_handle_packet ( void *object, IP_Port ip_port, uint8_t *data, uint32_t length )
+int rtp_handle_packet ( void *object, uint8_t *data, uint32_t length )
 {
     RTPSession *_session = object;
     RTPMessage *_msg;
@@ -570,11 +570,6 @@ int rtp_handle_packet ( void *object, IP_Port ip_port, uint8_t *data, uint32_t l
         return -1;
     }
 
-    /* Hopefully this goes well
-     * NOTE: Is this even used?
-     */
-    memcpy(&_msg->from, &ip_port, sizeof(IP_Port));
-
     /* Check if message came in late */
     if ( check_late_message(_session, _msg) < 0 ) { /* Not late */
         _session->rsequnum = _msg->header->sequnum;
diff --git a/toxav/rtp.h b/toxav/rtp.h
index 4d66e791..8b445540 100755
--- a/toxav/rtp.h
+++ b/toxav/rtp.h
@@ -75,7 +75,6 @@ typedef struct _RTPMessage {
 
     uint8_t       data[MAX_RTP_SIZE];
     uint32_t      length;
-    IP_Port   from;
 
     struct _RTPMessage   *next;
 } RTPMessage;
diff --git a/toxcore/Makefile.inc b/toxcore/Makefile.inc
index 0760952a..89fe4dc7 100644
--- a/toxcore/Makefile.inc
+++ b/toxcore/Makefile.inc
@@ -43,6 +43,8 @@ libtoxcore_la_SOURCES = ../toxcore/DHT.h \
                         ../toxcore/TCP_client.c \
                         ../toxcore/TCP_server.h \
                         ../toxcore/TCP_server.c \
+                        ../toxcore/list.c \
+                        ../toxcore/list.h \
                         ../toxcore/misc_tools.h
 
 libtoxcore_la_CFLAGS =  -I$(top_srcdir) \
diff --git a/toxcore/Messenger.c b/toxcore/Messenger.c
index 4a9e5f7f..e0ef5a28 100644
--- a/toxcore/Messenger.c
+++ b/toxcore/Messenger.c
@@ -715,6 +715,25 @@ static int send_ping(Messenger *m, int32_t friendnumber)
     return ret;
 }
 
+static int send_relays(Messenger *m, int32_t friendnumber)
+{
+    Node_format nodes[MAX_SHARED_RELAYS];
+    uint8_t data[1024];
+    int n, length;
+
+    n = copy_connected_tcp_relays(m->net_crypto, nodes, MAX_SHARED_RELAYS);
+    length = pack_nodes(data, sizeof(data), nodes, n);
+
+    int ret = write_cryptpacket_id(m, friendnumber, PACKET_ID_SHARE_RELAYS, data, length);
+
+    if (ret == 1)
+        m->friendlist[friendnumber].share_relays_lastsent = unix_time();
+
+    return ret;
+}
+
+
+
 static int set_friend_statusmessage(Messenger *m, int32_t friendnumber, uint8_t *status, uint16_t length)
 {
     if (friend_not_valid(m, friendnumber))
@@ -1681,46 +1700,35 @@ int m_msi_packet(Messenger *m, int32_t friendnumber, uint8_t *data, uint16_t len
     return write_cryptpacket_id(m, friendnumber, PACKET_ID_MSI, data, length);
 }
 
-static int32_t friendnum_from_ip_port(Messenger *m, IP_Port ip_port)
-{
-    uint32_t i;
-
-    for (i = 0; i < m->numonline_friends; ++i) {
-        if (ipport_equal(&m->online_friendlist[i].ip_port, &ip_port))
-            return m->online_friendlist[i].friend_num;
-    }
-
-    return -1;
-}
-
-static int handle_custom_user_packet(void *object, IP_Port source, uint8_t *packet, uint32_t length)
+static int handle_custom_user_packet(void *object, int friend_num, uint8_t *packet, uint16_t length)
 {
     Messenger *m = object;
-    int32_t friend_num = friendnum_from_ip_port(m, source);
 
-    if (friend_num == -1)
+    if (friend_not_valid(m, friend_num))
         return 1;
 
-    if (m->friendlist[friend_num].packethandlers[packet[0] % TOTAL_USERPACKETS].function)
-        return m->friendlist[friend_num].packethandlers[packet[0] % TOTAL_USERPACKETS].function(
-                   m->friendlist[friend_num].packethandlers[packet[0] % TOTAL_USERPACKETS].object, source, packet, length);
+    if (m->friendlist[friend_num].packethandlers[packet[0] % PACKET_ID_LOSSY_RANGE_SIZE].function)
+        return m->friendlist[friend_num].packethandlers[packet[0] % PACKET_ID_LOSSY_RANGE_SIZE].function(
+                   m->friendlist[friend_num].packethandlers[packet[0] % PACKET_ID_LOSSY_RANGE_SIZE].object, packet, length);
 
     return 1;
 }
 
 
-int custom_user_packet_registerhandler(Messenger *m, int32_t friendnumber, uint8_t byte, packet_handler_callback cb,
-                                       void *object)
+int custom_user_packet_registerhandler(Messenger *m, int32_t friendnumber, uint8_t byte,
+                                       int (*packet_handler_callback)(void *object, uint8_t *data, uint32_t len), void *object)
 {
     if (friend_not_valid(m, friendnumber))
         return -1;
 
-    if (byte < NET_PACKET_CUSTOM_RANGE_START || byte >= NET_PACKET_CUSTOM_RANGE_END)
+    if (byte < PACKET_ID_LOSSY_RANGE_START)
         return -1;
 
-    m->friendlist[friendnumber].packethandlers[byte % TOTAL_USERPACKETS].function = cb;
-    m->friendlist[friendnumber].packethandlers[byte % TOTAL_USERPACKETS].object = object;
-    networking_registerhandler(m->net, byte, handle_custom_user_packet, m);
+    if (byte >= (PACKET_ID_LOSSY_RANGE_START + PACKET_ID_LOSSY_RANGE_SIZE))
+        return -1;
+
+    m->friendlist[friendnumber].packethandlers[byte % PACKET_ID_LOSSY_RANGE_SIZE].function = packet_handler_callback;
+    m->friendlist[friendnumber].packethandlers[byte % PACKET_ID_LOSSY_RANGE_SIZE].object = object;
     return 0;
 }
 
@@ -1732,12 +1740,10 @@ int send_custom_user_packet(Messenger *m, int32_t friendnumber, uint8_t *data, u
     if (m->friendlist[friendnumber].status != FRIEND_ONLINE)
         return -1;
 
-    IP_Port ip_port = get_friend_ipport(m, friendnumber);
-
-    if (ip_port.port == 0)
+    if (m->friendlist[friendnumber].crypt_connection_id == -1)
         return -1;
 
-    return sendpacket(m->net, ip_port, data, length);
+    return send_lossy_cryptpacket(m->net_crypto, m->friendlist[friendnumber].crypt_connection_id, data, length);
 }
 
 
@@ -1776,6 +1782,7 @@ static int handle_new_connections(void *object, New_Connection *n_c)
         int id = accept_crypto_connection(m->net_crypto, n_c);
         connection_status_handler(m->net_crypto, id, &handle_status, m, friend_id);
         connection_data_handler(m->net_crypto, id, &handle_packet, m, friend_id);
+        connection_lossy_data_handler(m->net_crypto, id, &handle_custom_user_packet, m, friend_id);
         m->friendlist[friend_id].crypt_connection_id = id;
         set_friend_status(m, friend_id, FRIEND_CONFIRMED);
         return 0;
@@ -2162,6 +2169,20 @@ static int handle_packet(void *object, int i, uint8_t *temp, uint16_t len)
                 (*m->msi_packet)(m, i, data, data_length, m->msi_packet_userdata);
         }
 
+        case PACKET_ID_SHARE_RELAYS: {
+            Node_format nodes[MAX_SHARED_RELAYS];
+            int n;
+
+            if ((n = unpack_nodes(nodes, MAX_SHARED_RELAYS, NULL, data, data_length, 1)) == -1)
+                break;
+
+            int i;
+
+            for (i = 0; i < n; i++) {
+                add_tcp_relay(m->net_crypto, nodes[i].ip_port, nodes[i].client_id);
+            }
+        }
+
         default: {
             break;
         }
@@ -2187,8 +2208,8 @@ static int friend_new_connection(Messenger *m, int32_t friendnumber, uint8_t *re
     m->friendlist[friendnumber].crypt_connection_id = id;
     connection_status_handler(m->net_crypto, id, &handle_status, m, friendnumber);
     connection_data_handler(m->net_crypto, id, &handle_packet, m, friendnumber);
+    connection_lossy_data_handler(m->net_crypto, id, &handle_custom_user_packet, m, friendnumber);
     return 0;
-
 }
 
 /* TODO: Make this function not suck. */
@@ -2276,6 +2297,10 @@ void do_friends(Messenger *m)
                 m->friendlist[i].crypt_connection_id = -1;
                 set_friend_status(m, i, FRIEND_CONFIRMED);
             }
+
+            if (m->friendlist[i].share_relays_lastsent + FRIEND_SHARE_RELAYS_INTERVAL < temp_time) {
+                send_relays(m, i);
+            }
         }
     }
 }
diff --git a/toxcore/Messenger.h b/toxcore/Messenger.h
index b72a0831..e9447977 100644
--- a/toxcore/Messenger.h
+++ b/toxcore/Messenger.h
@@ -41,6 +41,7 @@
 
 /* NOTE: Packet ids below 16 must never be used. */
 #define PACKET_ID_ALIVE 16
+#define PACKET_ID_SHARE_RELAYS 17
 #define PACKET_ID_NICKNAME 48
 #define PACKET_ID_STATUSMESSAGE 49
 #define PACKET_ID_USERSTATUS 50
@@ -59,6 +60,9 @@
 /* Max number of groups we can invite someone at the same time to. */
 #define MAX_INVITED_GROUPS 64
 
+/* Max number of tcp relays sent to friends */
+#define MAX_SHARED_RELAYS 16
+
 /* Status definitions. */
 enum {
     NOFRIEND,
@@ -88,9 +92,13 @@ enum {
 /* Interval between the sending of ping packets. */
 #define FRIEND_PING_INTERVAL 5
 
+/* Interval between the sending of tcp relay information */
+#define FRIEND_SHARE_RELAYS_INTERVAL (5 * 60)
+
 /* If no packets are received from friend in this time interval, kill the connection. */
 #define FRIEND_CONNECTION_TIMEOUT (FRIEND_PING_INTERVAL * 2)
 
+
 /* USERSTATUS -
  * Represents userstatuses someone can have.
  */
@@ -153,12 +161,16 @@ typedef struct {
     uint32_t friendrequest_nospam; // The nospam number used in the friend request.
     uint64_t ping_lastrecv;
     uint64_t ping_lastsent;
+    uint64_t share_relays_lastsent;
     struct File_Transfers file_sending[MAX_CONCURRENT_FILE_PIPES];
     struct File_Transfers file_receiving[MAX_CONCURRENT_FILE_PIPES];
     int invited_groups[MAX_INVITED_GROUPS];
     uint16_t invited_groups_num;
 
-    Packet_Handles packethandlers[TOTAL_USERPACKETS];
+    struct {
+        int (*function)(void *object, uint8_t *data, uint32_t len);
+        void *object;
+    } packethandlers[PACKET_ID_LOSSY_RANGE_SIZE];
 } Friend;
 
 typedef struct {
@@ -688,8 +700,8 @@ int m_msi_packet(Messenger *m, int32_t friendnumber, uint8_t *data, uint16_t len
  * return -1 on failure.
  * return 0 on success.
  */
-int custom_user_packet_registerhandler(Messenger *m, int32_t friendnumber, uint8_t byte, packet_handler_callback cb,
-                                       void *object);
+int custom_user_packet_registerhandler(Messenger *m, int32_t friendnumber, uint8_t byte,
+                                       int (*packet_handler_callback)(void *object, uint8_t *data, uint32_t len), void *object);
 
 /* High level function to send custom user packets.
  *
diff --git a/toxcore/TCP_server.c b/toxcore/TCP_server.c
index ceab5f10..a47f74e2 100644
--- a/toxcore/TCP_server.c
+++ b/toxcore/TCP_server.c
@@ -99,15 +99,7 @@ static int realloc_connection(TCP_Server *TCP_server, uint32_t num)
  */
 static int get_TCP_connection_index(TCP_Server *TCP_server, uint8_t *public_key)
 {
-    //TODO optimize this function.
-    uint32_t i;
-
-    for (i = 0; i < TCP_server->size_accepted_connections; ++i) {
-        if (memcmp(TCP_server->accepted_connection_array[i].public_key, public_key, crypto_box_PUBLICKEYBYTES) == 0)
-            return i;
-    }
-
-    return -1;
+    return list_find(&TCP_server->accepted_key_list, public_key);
 }
 
 
@@ -148,12 +140,16 @@ static int add_accepted(TCP_Server *TCP_server, TCP_Secure_Connection *con)
         return -1;
     }
 
+    if (!list_add(&TCP_server->accepted_key_list, con->public_key, index))
+        return -1;
+
     memcpy(&TCP_server->accepted_connection_array[index], con, sizeof(TCP_Secure_Connection));
     TCP_server->accepted_connection_array[index].status = TCP_STATUS_CONFIRMED;
     ++TCP_server->num_accepted_connections;
     TCP_server->accepted_connection_array[index].identifier = ++TCP_server->counter;
     TCP_server->accepted_connection_array[index].last_pinged = unix_time();
     TCP_server->accepted_connection_array[index].ping_id = 0;
+
     return index;
 }
 
@@ -170,6 +166,9 @@ static int del_accepted(TCP_Server *TCP_server, int index)
     if (TCP_server->accepted_connection_array[index].status == TCP_STATUS_NO_STATUS)
         return -1;
 
+    if (!list_remove(&TCP_server->accepted_key_list, TCP_server->accepted_connection_array[index].public_key, index))
+        return -1;
+
     memset(&TCP_server->accepted_connection_array[index], 0, sizeof(TCP_Secure_Connection));
     --TCP_server->num_accepted_connections;
 
@@ -888,6 +887,9 @@ TCP_Server *new_TCP_server(uint8_t ipv6_enabled, uint16_t num_sockets, uint16_t
 
     memcpy(temp->public_key, public_key, crypto_box_PUBLICKEYBYTES);
     memcpy(temp->secret_key, secret_key, crypto_box_SECRETKEYBYTES);
+
+    list_init(&temp->accepted_key_list, crypto_box_PUBLICKEYBYTES);
+
     return temp;
 }
 
@@ -1040,6 +1042,8 @@ void kill_TCP_server(TCP_Server *TCP_server)
         set_callback_handle_recv_1(TCP_server->onion, NULL, NULL);
     }
 
+    list_free(&TCP_server->accepted_key_list);
+
     free(TCP_server->socks_listening);
     free(TCP_server);
 }
diff --git a/toxcore/TCP_server.h b/toxcore/TCP_server.h
index fc8c234b..7fd4d976 100644
--- a/toxcore/TCP_server.h
+++ b/toxcore/TCP_server.h
@@ -25,6 +25,7 @@
 
 #include "crypto_core.h"
 #include "onion.h"
+#include "list.h"
 
 #if defined(_WIN32) || defined(__WIN32__) || defined(WIN32) || defined(__MACH__)
 #define MSG_NOSIGNAL 0
@@ -110,6 +111,8 @@ typedef struct {
     uint32_t num_accepted_connections;
 
     uint64_t counter;
+
+    LIST accepted_key_list;
 } TCP_Server;
 
 /* Create new TCP server instance.
diff --git a/toxcore/list.c b/toxcore/list.c
new file mode 100644
index 00000000..2904d15b
--- /dev/null
+++ b/toxcore/list.c
@@ -0,0 +1,198 @@
+/* list.h
+ *
+ * Simple struct with functions to create a list which associates ids with data
+ * -Allows for finding ids associated with data such as IPs or public keys in a short time
+ * -Should only be used if there are relatively few add/remove calls to the list
+ *
+ *  Copyright (C) 2014 Tox project All Rights Reserved.
+ *
+ *  This file is part of Tox.
+ *
+ *  Tox is free software: you can redistribute it and/or modify
+ *  it under the terms of the GNU General Public License as published by
+ *  the Free Software Foundation, either version 3 of the License, or
+ *  (at your option) any later version.
+ *
+ *  Tox is distributed in the hope that it will be useful,
+ *  but WITHOUT ANY WARRANTY; without even the implied warranty of
+ *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ *  GNU General Public License for more details.
+ *
+ *  You should have received a copy of the GNU General Public License
+ *  along with Tox.  If not, see <http://www.gnu.org/licenses/>.
+ *
+ */
+
+#include "list.h"
+
+/* Basically, the elements in the list are placed in order so that they can be searched for easily
+ * -each element is seen as a big-endian integer when ordering them
+ * -the ids array is maintained so that each id always matches
+ * -the search algorithm cuts down the time to find the id associated with a piece of data
+ *   at the cost of slow add/remove functions for large lists
+ * -Starts at 1/2 of the array, compares the element in the array with the data,
+ *   then moves +/- 1/4 of the array depending on whether the value is greater or lower,
+ *   then +- 1/8, etc, until the value is matched or its position where it should be in the array is found
+ * -some considerations since the array size is never perfect
+ */
+
+#define INDEX(i) (~i)
+
+/* Find data in list
+ *
+ * return value:
+ *  >= 0 : id associated with data
+ *  < 0  : no match, returns index (return value is INDEX(index)) where
+ *         the data should be inserted
+ */
+static int find(LIST *list, void *data)
+{
+    //should work well, but could be improved
+    if (list->n == 0) {
+        return INDEX(0);
+    }
+
+    uint32_t i = list->n / 2; //current position in the array
+    uint32_t delta = i / 2;   //how much we move in the array
+
+    int d = -1; //used to determine if closest match is found
+    //closest match is found if we move back to where we have already been
+
+    while (1) {
+        int r = memcmp(data, list->data + list->size * i, list->size);
+
+        if (r == 0) {
+            return list->ids[i];
+        }
+
+        if (r > 0) {
+            //data is greater
+            //move down
+            i += delta;
+
+            if (d == 0 || i == list->n) {
+                //reached bottom of list, or closest match
+                return INDEX(i);
+            }
+
+            delta = (delta) / 2;
+
+            if (delta == 0) {
+                delta = 1;
+                d = 1;
+            }
+        } else {
+            //data is smaller
+            if (d == 1 || i == 0) {
+                //reached top or list or closest match
+                return INDEX(i);
+            }
+
+            //move up
+            i -= delta;
+
+            delta = (delta) / 2;
+
+            if (delta == 0) {
+                delta = 1;
+                d = 0;
+            }
+        }
+    }
+}
+
+
+void list_init(LIST *list, uint32_t element_size)
+{
+    //set initial values
+    list->n = 0;
+    list->size = element_size;
+    list->data = NULL;
+    list->ids = NULL;
+}
+
+void list_free(LIST *list)
+{
+    //free both arrays
+    free(list->data);
+    free(list->ids);
+}
+
+int list_find(LIST *list, void *data)
+{
+    int r = find(list, data);
+
+    //return only -1 and positive values
+    if (r < 0) {
+        r = -1;
+    }
+
+    return r;
+}
+
+int list_add(LIST *list, void *data, int id)
+{
+    //find where the new element should be inserted
+    //see: return value of find()
+    int i = find(list, data);
+
+    if (i >= 0) {
+        //already in list
+        return 0;
+    }
+
+    i = ~i;
+
+    //increase the size of the arrays by one
+    void *p;
+
+    p = realloc(list->data, list->size * (list->n + 1));
+
+    if (!p) {
+        return 0;
+    } else {
+        list->data = p;
+    }
+
+    p = realloc(list->ids, sizeof(int) * (list->n + 1));
+
+    if (!p) {
+        return 0;
+    } else {
+        list->ids = p;
+    }
+
+    //insert data to element array
+    memmove(list->data + (i + 1) * list->size, list->data + i * list->size, (list->n - i) * list->size);
+    memcpy(list->data + i * list->size, data, list->size);
+
+    //insert id to id array
+    memmove(&list->ids[i + 1], &list->ids[i], (list->n - i) * sizeof(int));
+    list->ids[i] = id;
+
+    //increase n
+    list->n++;
+
+    return 1;
+}
+
+int list_remove(LIST *list, void *data, int id)
+{
+    int i = find(list, data);
+
+    if (i < 0) {
+        return 0;
+    }
+
+    if (list->ids[i] != id) {
+        //this should never happen
+        return 0;
+    }
+
+    list->n--;
+
+    memmove(list->data + i * list->size, list->data + (i + 1) * list->size, (list->n - i) * list->size);
+    memmove(&list->ids[i], &list->ids[i + 1], (list->n - i) * sizeof(int));
+
+    return 1;
+}
diff --git a/toxcore/list.h b/toxcore/list.h
new file mode 100644
index 00000000..299c010d
--- /dev/null
+++ b/toxcore/list.h
@@ -0,0 +1,70 @@
+/* list.h
+ *
+ * Simple struct with functions to create a list which associates ids with data
+ * -Allows for finding ids associated with data such as IPs or public keys in a short time
+ * -Should only be used if there are relatively few add/remove calls to the list
+ *
+ *  Copyright (C) 2014 Tox project All Rights Reserved.
+ *
+ *  This file is part of Tox.
+ *
+ *  Tox is free software: you can redistribute it and/or modify
+ *  it under the terms of the GNU General Public License as published by
+ *  the Free Software Foundation, either version 3 of the License, or
+ *  (at your option) any later version.
+ *
+ *  Tox is distributed in the hope that it will be useful,
+ *  but WITHOUT ANY WARRANTY; without even the implied warranty of
+ *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ *  GNU General Public License for more details.
+ *
+ *  You should have received a copy of the GNU General Public License
+ *  along with Tox.  If not, see <http://www.gnu.org/licenses/>.
+ *
+ */
+
+#ifndef LIST_H
+#define LIST_H
+
+#include <stdlib.h>
+#include <stdint.h>
+#include <string.h>
+
+typedef struct {
+    uint32_t n; //number of elements
+    uint32_t size; //size of the elements
+    void *data; //array of elements
+    int *ids; //array of element ids
+} LIST;
+
+/* Initialize a list, element_size is the size of the elements in the list */
+void list_init(LIST *list, uint32_t element_size);
+
+/* Free a list initiated with list_init */
+void list_free(LIST *list);
+
+/* Retrieve the id of an element in the list
+ *
+ * return value:
+ *  >= 0 : id associated with data
+ *  -1   : failure
+ */
+int list_find(LIST *list, void *data);
+
+/* Add an element with associated id to the list
+ *
+ * return value:
+ *  1 : success
+ *  0 : failure (data already in list)
+ */
+int list_add(LIST *list, void *data, int id);
+
+/* Remove element from the list
+ *
+ * return value:
+ *  1 : success
+ *  0 : failure (element not found or id does not match
+ */
+int list_remove(LIST *list, void *data, int id);
+
+#endif
diff --git a/toxcore/net_crypto.c b/toxcore/net_crypto.c
index 875c639f..2269e041 100644
--- a/toxcore/net_crypto.c
+++ b/toxcore/net_crypto.c
@@ -1079,7 +1079,7 @@ static int handle_data_packet_helper(Net_Crypto *c, int crypt_connection_id, uin
     } else if (real_data[0] == PACKET_ID_KILL) {
         conn->killed = 1;
         return 0;
-    } else {
+    } else if (real_data[0] >= CRYPTO_RESERVED_PACKETS && real_data[0] < PACKET_ID_LOSSY_RANGE_START) {
         Packet_Data dt;
         dt.time = current_time_monotonic();
         dt.length = real_length;
@@ -1096,6 +1096,16 @@ static int handle_data_packet_helper(Net_Crypto *c, int crypt_connection_id, uin
 
         /* Packet counter. */
         ++conn->packet_counter;
+    } else if (real_data[0] >= PACKET_ID_LOSSY_RANGE_START &&
+               real_data[0] < (PACKET_ID_LOSSY_RANGE_START + PACKET_ID_LOSSY_RANGE_SIZE)) {
+
+        if (conn->connection_lossy_data_callback)
+            conn->connection_lossy_data_callback(conn->connection_lossy_data_callback_object,
+                                                 conn->connection_lossy_data_callback_id, real_data, real_length);
+
+        set_buffer_end(&conn->recv_array, num);
+    } else {
+        return -1;
     }
 
     if (conn->status == CRYPTO_CONN_NOT_CONFIRMED) {
@@ -2050,6 +2060,28 @@ int connection_data_handler(Net_Crypto *c, int crypt_connection_id, int (*connec
     return 0;
 }
 
+/* Set function to be called when connection with crypt_connection_id receives a lossy data packet of length.
+ *
+ * The set function should return -1 on failure and 0 on success.
+ * Object and id will be passed to this function untouched.
+ *
+ * return -1 on failure.
+ * return 0 on success.
+ */
+int connection_lossy_data_handler(Net_Crypto *c, int crypt_connection_id,
+                                  int (*connection_lossy_data_callback)(void *object, int id, uint8_t *data, uint16_t length), void *object, int id)
+{
+    Crypto_Connection *conn = get_crypto_connection(c, crypt_connection_id);
+
+    if (conn == 0)
+        return -1;
+
+    conn->connection_lossy_data_callback = connection_lossy_data_callback;
+    conn->connection_lossy_data_callback_object = object;
+    conn->connection_lossy_data_callback_id = id;
+    return 0;
+}
+
 /* Get the crypto connection id from the ip_port.
  *
  * return -1 on failure.
@@ -2211,8 +2243,12 @@ uint32_t crypto_num_free_sendqueue_slots(Net_Crypto *c, int crypt_connection_id)
 
 
 
-/*  return -1 if data could not be put in packet queue.
- *  return positive packet number if data was put into the queue.
+/* Sends a lossless cryptopacket.
+ *
+ * return -1 if data could not be put in packet queue.
+ * return positive packet number if data was put into the queue.
+ *
+ * The first byte of data must be in the CRYPTO_RESERVED_PACKETS to PACKET_ID_LOSSY_RANGE_START range.
  */
 int64_t write_cryptpacket(Net_Crypto *c, int crypt_connection_id, uint8_t *data, uint32_t length)
 {
@@ -2222,6 +2258,9 @@ int64_t write_cryptpacket(Net_Crypto *c, int crypt_connection_id, uint8_t *data,
     if (data[0] < CRYPTO_RESERVED_PACKETS)
         return -1;
 
+    if (data[0] >= PACKET_ID_LOSSY_RANGE_START)
+        return -1;
+
     Crypto_Connection *conn = get_crypto_connection(c, crypt_connection_id);
 
     if (conn == 0)
@@ -2243,6 +2282,31 @@ int64_t write_cryptpacket(Net_Crypto *c, int crypt_connection_id, uint8_t *data,
     return ret;
 }
 
+/* return -1 on failure.
+ * return 0 on success.
+ *
+ * Sends a lossy cryptopacket. (first byte must in the PACKET_ID_LOSSY_RANGE_*)
+ */
+int send_lossy_cryptpacket(Net_Crypto *c, int crypt_connection_id, uint8_t *data, uint32_t length)
+{
+    if (length == 0 || length > MAX_CRYPTO_DATA_SIZE)
+        return -1;
+
+    if (data[0] < PACKET_ID_LOSSY_RANGE_START)
+        return -1;
+
+    if (data[0] >= (PACKET_ID_LOSSY_RANGE_START + PACKET_ID_LOSSY_RANGE_SIZE))
+        return -1;
+
+    Crypto_Connection *conn = get_crypto_connection(c, crypt_connection_id);
+
+    if (conn == 0)
+        return -1;
+
+    return send_data_packet_helper(c, crypt_connection_id, conn->recv_array.buffer_start, conn->send_array.buffer_end, data,
+                                   length);
+}
+
 /* Kill a crypto connection.
  *
  * return -1 on failure.
diff --git a/toxcore/net_crypto.h b/toxcore/net_crypto.h
index 25f8c2f7..938046f1 100644
--- a/toxcore/net_crypto.h
+++ b/toxcore/net_crypto.h
@@ -69,6 +69,10 @@
 #define STATUS_TCP_INVISIBLE 2 /* we know the other peer is connected to this relay but he isn't appearing online */
 #define STATUS_TCP_ONLINE    3
 
+/* All packets starting with a byte in this range are considered lossy packets. */
+#define PACKET_ID_LOSSY_RANGE_START 192
+#define PACKET_ID_LOSSY_RANGE_SIZE 63
+
 typedef struct {
     uint64_t time;
     uint16_t length;
@@ -119,6 +123,10 @@ typedef struct {
     void *connection_data_callback_object;
     int connection_data_callback_id;
 
+    int (*connection_lossy_data_callback)(void *object, int id, uint8_t *data, uint16_t length);
+    void *connection_lossy_data_callback_object;
+    int connection_lossy_data_callback_id;
+
     uint64_t last_request_packet_sent;
 
     uint32_t packet_counter;
@@ -231,7 +239,7 @@ int set_direct_ip_port(Net_Crypto *c, int crypt_connection_id, IP_Port ip_port);
 int connection_status_handler(Net_Crypto *c, int crypt_connection_id, int (*connection_status_callback)(void *object,
                               int id, uint8_t status), void *object, int id);
 
-/* Set function to be called when connection with crypt_connection_id receives a data packet of length.
+/* Set function to be called when connection with crypt_connection_id receives a lossless data packet of length.
  *
  * The set function should return -1 on failure and 0 on success.
  * Object and id will be passed to this function untouched.
@@ -243,16 +251,38 @@ int connection_data_handler(Net_Crypto *c, int crypt_connection_id, int (*connec
                             int id, uint8_t *data, uint16_t length), void *object, int id);
 
 
+/* Set function to be called when connection with crypt_connection_id receives a lossy data packet of length.
+ *
+ * The set function should return -1 on failure and 0 on success.
+ * Object and id will be passed to this function untouched.
+ *
+ * return -1 on failure.
+ * return 0 on success.
+ */
+int connection_lossy_data_handler(Net_Crypto *c, int crypt_connection_id,
+                                  int (*connection_lossy_data_callback)(void *object, int id, uint8_t *data, uint16_t length), void *object, int id);
+
 /* returns the number of packet slots left in the sendbuffer.
  * return 0 if failure.
  */
 uint32_t crypto_num_free_sendqueue_slots(Net_Crypto *c, int crypt_connection_id);
 
-/*  return -1 if data could not be put in packet queue.
- *  return positive packet number if data was put into the queue.
+/* Sends a lossless cryptopacket.
+ *
+ * return -1 if data could not be put in packet queue.
+ * return positive packet number if data was put into the queue.
+ *
+ * The first byte of data must be in the CRYPTO_RESERVED_PACKETS to PACKET_ID_LOSSY_RANGE_START range.
  */
 int64_t write_cryptpacket(Net_Crypto *c, int crypt_connection_id, uint8_t *data, uint32_t length);
 
+/* return -1 on failure.
+ * return 0 on success.
+ *
+ * Sends a lossy cryptopacket. (first byte must in the PACKET_ID_LOSSY_RANGE_*)
+ */
+int send_lossy_cryptpacket(Net_Crypto *c, int crypt_connection_id, uint8_t *data, uint32_t length);
+
 /* Add a tcp relay, associating it to a crypt_connection_id.
  *
  * return 0 if it was added.
diff --git a/toxcore/network.h b/toxcore/network.h
index 0eb7bbd0..633f8010 100644
--- a/toxcore/network.h
+++ b/toxcore/network.h
@@ -122,12 +122,6 @@ typedef int sock_t;
 #define NET_PACKET_LAN_DISCOVERY   33  /* LAN discovery packet ID. */
 #define NET_PACKET_GROUP_CHATS     48  /* Group chats packet ID. */
 
-/* Range of ids that custom user packets can use. */
-#define NET_PACKET_CUSTOM_RANGE_START 64
-#define NET_PACKET_CUSTOM_RANGE_END 96
-
-#define TOTAL_USERPACKETS (NET_PACKET_CUSTOM_RANGE_END - NET_PACKET_CUSTOM_RANGE_START)
-
 /* See:  docs/Prevent_Tracking.txt and onion.{c, h} */
 #define NET_PACKET_ONION_SEND_INITIAL 128
 #define NET_PACKET_ONION_SEND_1 129