diff --git src/message.c src/message.c
index 1892a33..3dea0d2 100644
--- src/message.c
+++ src/message.c
@@ -1306,8 +1306,33 @@ guint32 message_ike_auth_i_payload_next(struct session *session, guint32 curr)
 
 #ifdef MOBIKE
 	case (N_MOBIKE_SUPPORTED << 8 | IKEV2_PAYLOAD_NOTIFY):
-		next = IKEV2_PAYLOAD_SA;
+
+		if(session->local_ipv4_addresses_ptr)
+			next = (N_ADDITIONAL_IP4_ADDRESS << 8 | IKEV2_PAYLOAD_NOTIFY);
+		else if(session->local_ipv6_addresses_ptr)
+			next = (N_ADDITIONAL_IP6_ADDRESS << 8 | IKEV2_PAYLOAD_NOTIFY);
+		else
+			next = IKEV2_PAYLOAD_SA;
 		break;
+
+	case (N_ADDITIONAL_IP4_ADDRESS << 8 | IKEV2_PAYLOAD_NOTIFY):
+
+		if(session->local_ipv4_addresses_ptr->next)
+			next = (N_ADDITIONAL_IP4_ADDRESS << 8 | IKEV2_PAYLOAD_NOTIFY);
+		else if(session->local_ipv6_addresses_ptr)
+			next = (N_ADDITIONAL_IP6_ADDRESS << 8 | IKEV2_PAYLOAD_NOTIFY);
+		else
+			next = IKEV2_PAYLOAD_SA;
+		break;
+
+	case (N_ADDITIONAL_IP6_ADDRESS << 8 | IKEV2_PAYLOAD_NOTIFY):
+
+		if(session->local_ipv6_addresses_ptr->next)
+			next = (N_ADDITIONAL_IP4_ADDRESS << 8 | IKEV2_PAYLOAD_NOTIFY);
+		else
+			next = IKEV2_PAYLOAD_SA;
+		break;
+
 #endif /* MOBIKE */
 
 	case IKEV2_PAYLOAD_SA:
@@ -1360,9 +1385,26 @@ int message_send_ike_auth_i(struct session *session)
 	guint32 enclen, ilen, payloadid_len = 0;
 	GSList *certs_for_peer;
 	GSList *sig_ca_items = NULL, *hash_ca_items = NULL;
+#ifdef MOBIKE
+	/*
+	 * IPv4 and IPv6 address buffers
+	 */
+	unsigned long addr;
+	char addr6[16];
+
+	struct network_address *addr_data;
+
+	GSList *lcl4ptr, *lcl6ptr;
+#endif /* MOBIKE */
 
 	LOG_FUNC_START(1);
 
+#ifdef MOBIKE
+	session->ike_auth_exchange_counter++;
+
+	session->local_ipv4_addresses_ptr = session->local_ipv4_addresses;
+	session->local_ipv6_addresses_ptr = session->local_ipv6_addresses;
+#endif /* MOBIKE */
 	retval = -1;
 	buffer = NULL;
 
@@ -1597,6 +1639,33 @@ int message_send_ike_auth_i(struct session *session)
 			LOG_DEBUG("Created MOBIKE_SUPPORTED notification");
 			LOG_TRACE("Created NOTIFY payload len = %u", len);
 			break;
+
+		case (N_ADDITIONAL_IP4_ADDRESS << 8 | IKEV2_PAYLOAD_NOTIFY):
+			lcl4ptr = session->local_ipv4_addresses_ptr;
+			addr_data = (struct network_address *)(lcl4ptr->data);
+			addr = 0;
+			addr_data->netaddr;
+			/*->sin.sin_addr.s_addr;*/
+
+			len = payload_notify_mobike_create(next, N_ADDITIONAL_IP4_ADDRESS,
+						(char *)addr, (guint16)(htons(sizeof(addr))), p);
+			LOG_DEBUG("Created ADDITIONAL_IP4_ADDRESS notification");
+			LOG_TRACE("Created NOTIFY payload len = %u", len);
+			session->local_ipv4_addresses_ptr =
+					session->local_ipv4_addresses_ptr->next;
+			break;
+
+		case (N_ADDITIONAL_IP6_ADDRESS << 8 | IKEV2_PAYLOAD_NOTIFY):
+			addr6 =
+				session->local_ipv6_addresses_ptr->data->netaddr->sin6.sin6_addr.s6_addr;
+
+			len = payload_notify_mobike_create(next, N_ADDITIONAL_IP6_ADDRESS,
+						addr6, (guint16)(htons(sizeof(addr6))), p);
+			LOG_DEBUG("Created ADDITIONAL_IP6_ADDRESS notification");
+			LOG_TRACE("Created NOTIFY payload len = %u", len);
+			session->local_ipv6_addresses_ptr =
+					session->local_ipv6_addresses_ptr->next;
+			break;
 #endif /* MOBIKE */
 		}
 
@@ -1770,8 +1839,33 @@ guint32 message_ike_auth_r_payload_next(struct session *session, guint32 curr)
 
 #ifdef MOBIKE
 	case (N_MOBIKE_SUPPORTED << 8 | IKEV2_PAYLOAD_NOTIFY):
-		next = IKEV2_PAYLOAD_SA;
+
+		if(session->local_ipv4_addresses_ptr)
+			next = (N_ADDITIONAL_IP4_ADDRESS << 8 | IKEV2_PAYLOAD_NOTIFY);
+		else if(session->local_ipv6_addresses_ptr)
+			next = (N_ADDITIONAL_IP6_ADDRESS << 8 | IKEV2_PAYLOAD_NOTIFY);
+		else
+			next = IKEV2_PAYLOAD_SA;
 		break;
+
+	case (N_ADDITIONAL_IP4_ADDRESS << 8 | IKEV2_PAYLOAD_NOTIFY):
+
+		if(session->local_ipv4_addresses_ptr->next)
+			next = (N_ADDITIONAL_IP4_ADDRESS << 8 | IKEV2_PAYLOAD_NOTIFY);
+		else if(session->local_ipv6_addresses_ptr)
+			next = (N_ADDITIONAL_IP6_ADDRESS << 8 | IKEV2_PAYLOAD_NOTIFY);
+		else
+			next = IKEV2_PAYLOAD_SA;
+		break;
+
+	case (N_ADDITIONAL_IP6_ADDRESS << 8 | IKEV2_PAYLOAD_NOTIFY):
+
+		if(session->local_ipv6_addresses_ptr->next)
+			next = (N_ADDITIONAL_IP4_ADDRESS << 8 | IKEV2_PAYLOAD_NOTIFY);
+		else
+			next = IKEV2_PAYLOAD_SA;
+		break;
+
 #endif /* MOBIKE */
 
 	case IKEV2_PAYLOAD_SA:
@@ -1826,9 +1920,23 @@ int message_send_ike_auth_r(struct session *session,
 	gpointer payloadid = NULL;
 	int auth_payload_len, payloadid_len = 0;
 	GSList *certs_for_peer;
+#ifdef MOBIKE
+	/*
+	 * IPv4 and IPv6 address buffers
+	 */
+	unsigned long addr;
+	char addr6[16];
+
+	struct network_address *addr_data;
+#endif /* MOBIKE */
 
 	LOG_FUNC_START(1);
 
+#ifdef MOBIKE
+	session->local_ipv4_addresses_ptr = session->local_ipv4_addresses;
+	session->local_ipv6_addresses_ptr = session->local_ipv6_addresses;
+#endif /* MOBIKE */
+
 	/*
 	 * Find corresponding CHILD SA structure
 	 */
@@ -2022,6 +2130,34 @@ int message_send_ike_auth_r(struct session *session,
 			LOG_DEBUG("Created MOBIKE_SUPPORTED notification");
 			LOG_TRACE("Created NOTIFY payload len = %u", len);
 			break;
+
+		case (N_ADDITIONAL_IP4_ADDRESS << 8 | IKEV2_PAYLOAD_NOTIFY):
+			/* addr_data = (struct netaddr *) */
+/*			*((struct network_address *)
+					g_slist_nth_data(session->local_ipv4_addresses_ptr, 0));
+			addr = 0;
+			addr_data; */
+			/*->sin.sin_addr.s_addr;*/
+
+			len = payload_notify_mobike_create(next, N_ADDITIONAL_IP4_ADDRESS,
+						(char *)addr, (guint16)(htons(sizeof(addr))), p);
+			LOG_DEBUG("Created ADDITIONAL_IP4_ADDRESS notification");
+			LOG_TRACE("Created NOTIFY payload len = %u", len);
+			session->local_ipv4_addresses_ptr =
+					session->local_ipv4_addresses_ptr->next;
+			break;
+
+		case (N_ADDITIONAL_IP6_ADDRESS << 8 | IKEV2_PAYLOAD_NOTIFY):
+/*			addr6 =
+				session->local_ipv6_addresses_ptr->data->netaddr->sin6.sin6_addr.s6_addr;
+*/
+			len = payload_notify_mobike_create(next, N_ADDITIONAL_IP6_ADDRESS,
+						addr6, (guint16)(htons(sizeof(addr6))), p);
+			LOG_DEBUG("Created ADDITIONAL_IP6_ADDRESS notification");
+			LOG_TRACE("Created NOTIFY payload len = %u", len);
+			session->local_ipv6_addresses_ptr =
+					session->local_ipv6_addresses_ptr->next;
+			break;
 #endif /* MOBIKE */
 
 		}
@@ -4366,9 +4502,27 @@ gint message_parse_ike_auth_i(struct ikev2_header *hdr, gchar *p,
 	guint32 r1, r2;
 	struct cert *cert;
 	struct certreq *certreq;
+#ifdef MOBIKE
+	gboolean no_additional_addresses = FALSE;
+	struct netaddr *peer_addr;
+	guint16 mobike_notify_len;
+#endif /* MOBIKE */
 
 	LOG_FUNC_START(1);
 
+#ifdef MOBIKE
+	/*
+	 * Create peer's address list of only one element at the moment -
+	 * source address found in header.
+	 */
+	if(netaddr_get_family(msg->srcaddr) == AF_INET)
+		msg->ike_auth.peer_ipv4_addresses =
+				g_slist_append(NULL, msg->srcaddr);
+	else if(netaddr_get_family(msg->srcaddr) == AF_INET6)
+		msg->ike_auth.peer_ipv6_addresses =
+				g_slist_append(NULL, msg->srcaddr);
+#endif /* MOBIKE */
+
 	/*
 	 * Assume that error occured...
 	 */
@@ -4704,7 +4858,7 @@ gint message_parse_ike_auth_i(struct ikev2_header *hdr, gchar *p,
 			}
 
 
-			LOG_DEBUG("Received N_MOBIKE_SUPPORTED notification!");
+			LOG_DEBUG("Received MOBIKE_SUPPORTED notification!");
 			msg->ike_auth.peer_supports_mobike = TRUE;
 
 			if ((r2 = message_find_next_payload(&p, &ptype, hdr))) {
@@ -4715,6 +4869,63 @@ gint message_parse_ike_auth_i(struct ikev2_header *hdr, gchar *p,
 
 			np = (struct payload_notify *)p;
 		}
+
+		/*
+		 * Process ADDITIONAL_*_ADDRESS notify payloads
+		 */
+		while(ptype == IKEV2_PAYLOAD_NOTIFY &&
+			(ntohs(np->n_type) == N_ADDITIONAL_IP4_ADDRESS ||
+			 ntohs(np->n_type) == N_ADDITIONAL_IP6_ADDRESS)) {
+
+			if (payload_notify_check(p) < 0) {
+				r1 |= MSGPARSE_SEND_NOTIFY;
+				msg->notify = N_INVALID_SYNTAX;
+				goto out;
+			}
+
+			payload_notify_parse(&peer_addr, &mobike_notify_len, p);
+
+			if(ntohs(np->n_type) == N_ADDITIONAL_IP4_ADDRESS) {
+				LOG_DEBUG("Received ADDITIONAL_IP4_ADDRESS notification");
+				msg->ike_auth.peer_ipv4_addresses = g_slist_prepend(
+						msg->ike_auth.peer_ipv4_addresses, peer_addr);
+			}
+			else {
+				LOG_DEBUG("Received ADDITIONAL_IP4_ADDRESS notification");
+				msg->ike_auth.peer_ipv6_addresses = g_slist_prepend(
+						msg->ike_auth.peer_ipv6_addresses, peer_addr);
+			}
+
+			if ((r2 = message_find_next_payload(&p, &ptype, hdr))) {
+				r1 |= (r2 & 0xFFFF0000);
+				msg->notify = r2 & 0xFFFF;
+				goto out;
+			}
+
+			np = (struct payload_notify *)p;
+		}
+
+		if (ptype == IKEV2_PAYLOAD_NOTIFY &&
+			ntohs(np->n_type) == N_NO_ADDITIONAL_ADDRESSES) {
+
+			if (payload_notify_check(p) < 0) {
+				r1 |= MSGPARSE_SEND_NOTIFY;
+				msg->notify = N_INVALID_SYNTAX;
+				goto out;
+			}
+
+			no_additional_addresses = TRUE;
+
+			LOG_DEBUG("Received NO_ADDITIONAL_ADDRESSES notification!");
+
+			if ((r2 = message_find_next_payload(&p, &ptype, hdr))) {
+				r1 |= (r2 & 0xFFFF0000);
+				msg->notify = r2 & 0xFFFF;
+				goto out;
+			}
+
+			np = (struct payload_notify *)p;
+		}
 #endif /* MOBIKE */
 
 		if (ptype == IKEV2_PAYLOAD_SA) {
@@ -4807,6 +5018,25 @@ gint message_parse_ike_auth_i(struct ikev2_header *hdr, gchar *p,
 	}
 
 	/*
+	 * Check if we received N_NO_ADDITIONAL_ADDRESSES and if so,
+	 * assert header source address is the only one, hence there was
+	 * no ADDITIONAL_*_ADDRESS notify payload.
+	 */
+#ifdef MOBIKE
+	if(no_additional_addresses == TRUE)
+		if((msg->ike_auth.peer_ipv4_addresses &&
+			msg->ike_auth.peer_ipv4_addresses->next) ||
+		   (msg->ike_auth.peer_ipv6_addresses &&
+			msg->ike_auth.peer_ipv6_addresses->next)) {
+			LOG_ERROR("Received notify payload for additional address as"
+					  "well as NO_ADDITIONAL_ADDRESSES");
+			r1 |= MSGPARSE_SEND_NOTIFY;
+			msg->notify = N_INVALID_SYNTAX;
+			goto out;
+		}
+#endif MOBIKE
+
+	/*
 	 * No error occured...
 	 */
 	r1 = 0;
@@ -4896,9 +5126,27 @@ gint message_parse_ike_auth_r(struct ikev2_header *hdr, gchar *p,
 	guint32 r1, r2;
 	struct cert *cert;
 	gboolean error;
+#ifdef MOBIKE
+	gboolean no_additional_addresses = FALSE;
+	struct netaddr *peer_addr;
+	guint16 mobike_notify_len;
+#endif /* MOBIKE */
 
 	LOG_FUNC_START(1);
 
+#ifdef MOBIKE
+	/*
+	 * Create peer's address list of only one element at the moment -
+	 * source address found in header.
+	 */
+	if(netaddr_get_family(msg->srcaddr) == AF_INET)
+		msg->ike_auth.peer_ipv4_addresses =
+				g_slist_append(NULL, msg->srcaddr);
+	else if(netaddr_get_family(msg->srcaddr) == AF_INET6)
+		msg->ike_auth.peer_ipv6_addresses =
+				g_slist_append(NULL, msg->srcaddr);
+#endif /* MOBIKE */
+
 	/*
 	 * Assume that error occured...
 	 */
@@ -5126,6 +5374,23 @@ gint message_parse_ike_auth_r(struct ikev2_header *hdr, gchar *p,
 			case N_MOBIKE_SUPPORTED:
 				msg->ike_auth.peer_supports_mobike = TRUE;
 				break;
+
+			case N_ADDITIONAL_IP4_ADDRESS:
+				payload_notify_parse(&peer_addr, &mobike_notify_len, p);
+				msg->ike_auth.peer_ipv4_addresses = g_slist_prepend(
+						msg->ike_auth.peer_ipv4_addresses, peer_addr);
+				break;
+
+			case N_ADDITIONAL_IP6_ADDRESS:
+				payload_notify_parse(&peer_addr, &mobike_notify_len, p);
+				msg->ike_auth.peer_ipv6_addresses = g_slist_prepend(
+						msg->ike_auth.peer_ipv6_addresses, peer_addr);
+				break;
+
+			case N_NO_ADDITIONAL_ADDRESSES:
+				no_additional_addresses = TRUE;
+				break;
+
 #endif /*MOBIKE */
 
 			default:
@@ -5252,6 +5517,25 @@ out_finish:
 	}
 
 	/*
+	 * Check if we received N_NO_ADDITIONAL_ADDRESSES and if so,
+	 * assert header source address is the only one, hence there was
+	 * no ADDITIONAL_*_ADDRESS notify payload.
+	 */
+#ifdef MOBIKE
+	if(no_additional_addresses == TRUE)
+		if((msg->ike_auth.peer_ipv4_addresses &&
+			msg->ike_auth.peer_ipv4_addresses->next) ||
+		   (msg->ike_auth.peer_ipv6_addresses &&
+			msg->ike_auth.peer_ipv6_addresses->next)) {
+			LOG_ERROR("Received notify payload for additional address as"
+					  "well as NO_ADDITIONAL_ADDRESSES");
+			r1 |= MSGPARSE_SEND_NOTIFY;
+			msg->notify = N_INVALID_SYNTAX;
+			goto out;
+		}
+#endif MOBIKE
+
+	/*
 	 * No error occured...
 	 */
 	r1 = 0;
diff --git src/message_msg.h src/message_msg.h
index 35912bd..b6231a4 100644
--- src/message_msg.h
+++ src/message_msg.h
@@ -133,7 +133,7 @@ struct ike_sa_init {
 struct ike_auth {
 
 	/**
-	 * Does initiator requested transport mode?
+	 * Has initiator requested transport mode?
 	 */
 	gint transport_mode:1;
 
@@ -245,6 +245,14 @@ struct ike_auth {
 	 */
 	GSList *cert_list;
 	GSList *certreq_list;
+
+	/**
+	 * Lists of remote peer's IPv4 and IPv6 addresses
+	 */
+#ifdef MOBIKE
+	GSList *peer_ipv4_addresses;
+	GSList *peer_ipv6_addresses;
+#endif /* MOBIKE */
 };
 
 /**
diff --git src/network.c src/network.c
index 342b5de..5069923 100644
--- src/network.c
+++ src/network.c
@@ -1676,3 +1676,182 @@ out:
 	return retval;
 }
 
+/**
+  * Compares two interfaces by name and index.
+  *
+  * @param ni1		First interface to compare
+  * @param ni2		Second interface to compare
+  *
+  * \return 1		If two interfaces differ by name or index or both
+  *		0			Otherwise
+  */
+int network_compare_interfaces(struct netif *ni1, struct netif *ni2) {
+
+	LOG_FUNC_START(1);
+
+	if(strcmp(netif_get_name(ni1), netif_get_name(ni2)))
+		return 1;
+
+	LOG_FUNC_END(1);
+
+	return ni1->if_index == ni2->if_index ? 0 : 1;
+}
+
+/**
+ * Compares interfaces in two network_data structures.
+ *
+ * @param data1		First network_data data which interfaces are to be compared
+ * @param data2		Second network_data data to be compared to data1 interfaces
+ *
+ * \return	1	If interfaces in data1 and data2 differ
+ *		0	otherwise
+ */
+int network_compare_interface_lists(struct network_data *data1,
+									struct network_data *data2) {
+
+	int retval;
+	GSList *list1, *list2;
+
+	LOG_FUNC_START(1);
+
+	retval = 0;
+
+	list1 = data1->interfaces;
+	list2 = data2->interfaces;
+
+	/*
+	 * Iterate through both interface lists one interface at a time
+	 */
+	while(list1 && list2 && !retval) {
+
+		if(network_compare_interfaces(list1->data, list2->data))
+			retval = 1;
+
+		list1 = list1->next;
+		list2 = list2->next;
+	}
+
+	if(list1 || list2)
+		retval = 1;
+
+	LOG_FUNC_END(1);
+
+	return retval;
+}
+
+
+/**
+ * Compares addresses in two network_data structures.
+ *
+ * @param data1		First network_data data which addresses are to be compared
+ * @param data2		Second network_data data to be compared to data1 addresses
+ *
+ * \return	1	If addresses in data1 and data2 differ
+ *		0	otherwise
+ */
+int network_compare_address_lists(struct network_data *data1,
+											struct network_data *data2) {
+
+	int retval;
+	GSList *list1, *list2;
+	struct network_address *a1, *a2;
+
+	LOG_FUNC_START(1);
+
+	retval = 0;
+
+	list1 = data1->addresses;
+	list2 = data2->addresses;
+
+	/*
+	 * Iterate through both address lists one address at a time
+	 */
+	while(list1 && list2 && !retval) {
+
+		a1 = (struct network_addresss *)(list1->data);
+		a2 = (struct network_addresss *)(list2->data);
+
+		if(netaddr_same_family(a1->netaddr, a2->netaddr)) {
+			if(netaddr_cmp_ip2ip(a1->netaddr, a2->netaddr))
+				retval = 1;
+		}
+		else
+			retval = 1;
+
+
+		list1 = list1->next;
+		list2 = list2->next;
+	}
+
+	if(list1 || list2)
+		retval = 1;
+
+	LOG_FUNC_END(1);
+
+	return retval;
+}
+
+/**
+  * Checks for changes in network interfaces and addresses.
+  */
+void network_check_links() {
+
+	struct network_data *network_data_new;
+	gboolean queue_message;
+
+	LOG_FUNC_START(1);
+
+	network_data_new = g_malloc0(sizeof(struct network_data));
+	queue_message = FALSE;
+
+	/*
+	 * TODO: what does context represent?
+	 */
+	network_data_new->context = NULL;
+
+	/*
+	 * Lock interfaces and addresses in network_data for reading
+	 */
+	g_static_rw_lock_reader_lock(&network_data->interfaces_lock);
+	g_static_rw_lock_reader_lock(&network_data->addresses_lock);
+
+	if (network_enumerate_interfaces(network_data_new) < 0)
+		goto out;
+
+	/*
+	 * Search for IPv4 addresses
+	 */
+	if (network_enumerate_addresses(network_data_new, AF_INET) < 0)
+		goto out;
+
+	/*
+	* Search for IPv6 addresses
+	*/
+	if (network_enumerate_addresses(network_data_new, AF_INET6) < 0)
+		goto out;
+
+	/*
+	* Compare interfaces and addresses
+	*/
+	if(network_compare_interface_lists(network_data_new, network_data))
+		queue_message = TRUE;
+	else if(network_compare_address_lists(network_data_new, network_data))
+		queue_message = TRUE;
+
+	/*
+	 * Send message to some queue if interfaces or addresses have changed
+	 */
+	if(queue_message == TRUE) {
+		/*
+		 * Tu treba poslati neku poruku (treba ju oblikovati) u neki red.
+		 * Netko po primitku te poruke treba izbrisati postojei automat
+		 * stanja parova IP adresa
+		 */
+	}
+
+out:
+	g_static_rw_lock_reader_unlock(&network_data->interfaces_lock);
+	g_static_rw_lock_reader_unlock(&network_data->addresses_lock);
+
+	LOG_FUNC_END(1);
+}
diff --git src/network.h src/network.h
index f928577..9a6d519 100644
--- src/network.h
+++ src/network.h
@@ -181,8 +181,8 @@ struct network_data {
 	 *
 	 * TODO: This has to be converted into hash indexed by interface name
 	 */
+	GStaticRWLock interfaces_lock;
 	GSList *interfaces;
-
 };
 
 #else /* __NETWORK_C */
diff --git src/payload.c src/payload.c
index 1cd2f20..79e274f 100644
--- src/payload.c
+++ src/payload.c
@@ -1157,6 +1157,10 @@ gint32 payload_notify_parse(void **data, guint16 *notify_data_len, char *p)
 	p += sizeof(struct payload_notify);
 	ntype = ntohs(np->n_type);
 
+	/*
+	 * Be careful about this check because MOBIKE introduces
+	 * new notify payloads with ntype > 16395
+	 */
 	if (ntype == 0
 		|| (ntype > 39 && ntype < 16384)
 		|| (ntype > 16395)) {
@@ -1227,6 +1231,19 @@ gint32 payload_notify_parse(void **data, guint16 *notify_data_len, char *p)
 		*((guint32 *)(*data)) = *((guint32 *)p);
 		break;
 
+#ifdef MOBIKE
+	case N_MOBIKE_SUPPORTED:
+	case NO_ADDITIONAL_ADDRESSES:
+		break;
+
+	case N_ADDITIONAL_IP4_ADDRESS:
+	case N_ADDITIONAL_IP4_ADDRESS:
+		*data = p;
+		*notify_data_len = ntohs(np->length) -
+						   sizeof(struct payload_notify);
+		break;
+#endif /* MOBIKE */
+
 	default:
 		printf ("ERROR: Unknown/unsupported notify (0x%x) in "
 			"%s:%s:%d\n", 
diff --git src/session.c src/session.c
index 9569983..7c0aae9 100644
--- src/session.c
+++ src/session.c
@@ -123,6 +123,14 @@ struct session *session_new(void)
 
 	session->embedded_sm_msg = NULL;
 
+	session->peer_addresses = NULL;
+
+#ifdef MOBIKE
+	ike_auth_exchange_counter = 0;
+
+	session_local_addresses_init(session);
+#endif /* MOBIKE */
+
 	LOG_FUNC_END(2);
 
 	return session;
@@ -251,6 +259,7 @@ gboolean session_free(struct session *session)
 		if (session->sent_resp_mux)
 			g_mutex_free(session->sent_resp_mux);
 
+		if (session)
 		g_free (session);
 
 	} else {
@@ -1093,3 +1102,47 @@ gboolean session_use_radius(struct session *session)
 #endif
 		return FALSE;
 }
+
+#ifdef MOBIKE
+GSList *session_add_address(GSList *list,
+								 struct netaddr *addr) {
+
+	GSList *new_address = NULL;
+
+	LOG_FUNC_START(1);
+
+	new_address = g_slist_prepend(new_address, addr);
+	new_address = g_slist_prepend(list, new_address);
+
+	LOG_FUNC_END(1);
+
+	return new_address;
+}
+
+void session_local_addresses_init(struct session *session) {
+
+	GSList *network_data_iterator;
+	struct network_address *addr;
+
+	LOG_FUNC_START(1);
+
+	network_data_iterator = network_data->addresses;
+
+	session->local_ipv4_addresses = NULL;
+	session->local_ipv6_addresses = NULL;
+
+	while(network_data_iterator) {
+		addr = (struct network_address *)network_data_iterator->data;
+		if(addr->netaddr->sin->sa.sa_family == AF_INET)
+			session->local_ipv4_addresses =
+					session_add_address(session->local_ipv4_addresses, addr);
+		else
+			session->local_ipv6_addresses =
+					session_add_address(session->local_ipv6_addresses, addr);
+
+		network_data_iterator = network_data_iterator->next;
+	}
+
+	LOG_FUNC_END(1);
+}
+#endif /* MOBIKE */
diff --git src/session.h src/session.h
index ed6202e..0747754 100644
--- src/session.h
+++ src/session.h
@@ -92,6 +92,41 @@
 #define MAX_HALF_OPENED_SESSIONS	2
 
 /**
+ * Structure for holding local and remote addresses making pair of addresses
+ * in a IP addresses state machine.
+ */
+struct pair_of_addresses {
+	/**
+	 * One of initiator's and one of responder's addresses.
+	 *
+	 * Those addresses also hold ports!
+	 */
+	struct netaddr *i_addr, *r_addr;
+
+	/**
+	 * State of address pair in IP Address Pair State Machine.
+	 *
+	 * Possible states are:
+	 *
+	 * ADDRESS_PAIR_INVALID			0
+	 * ADDRESS_PAIR_VALID			1
+	 * ADDRESS_PAIR_NEGOTIATING		2
+	 * ADDRESS_PAIR_ACTIVE			3
+	 * ADDRESS_PAIR_TRANSITING		4
+	 * ADDRESS_PAIR_INEXISTING		5
+	 *
+	 * Default state is ADDRESS_PAIR_INVALID.
+	 */
+	guint8 state;
+
+	/**
+	 * These are the time fields for return routability check timeout.
+	 */
+	GTimeVal rrc_timeout;
+	timeout_t *to;
+};
+
+/**
  * In the following structure all the fields marked as transient are
  * valid only throughout some particular lifetime of IKE SA, e.g.
  * during cration, rekeying, reautentification, etc.
@@ -288,6 +323,24 @@ struct session {
 	 */
 	struct netaddr *i_addr, *r_addr;
 
+	/**
+	 * List of remote peer's IPv4 and IPv6 addresses
+	 */
+	GSList *peer_ipv4_addresses;
+	GSList *peer_ipv6_addresses;
+
+	/**
+	 * List of pair of addresses, their states and timeouts in
+	 * IP address state machine in MOBIKE.
+	 * One pair consists of initiator's address and of respodnder's address.
+	 */
+	GSList *pair_of_addresses_list;
+	/**
+	 * Pointer to active address from pair_of_addresses_list list
+	 * TODO: This variable should replace i_addr and r_addr variables.
+	 */
+	GSList *active_address_pair;
+
 #ifdef SUPPLICANT
 	/**
 	 * Pointer to a structure with EAP states 
@@ -452,6 +505,35 @@ struct session {
 	 */
 #ifdef MOBIKE
 	gboolean mobike_supported;
+
+	/**
+	 * Counter for IKE AUTH exchanges. It serves for determining if
+	 * particular exchange contains SA payload, hence 1st IKE AUTH
+	 * exchange.
+	 */
+	guint8 ike_auth_exchange_counter;
+
+	/*
+	 * Lists of local IP addresses initialized in network_init() function.
+	 * Temporary pointers are needed for ADDITIONAL_*_ADDRESS notify
+	 * payloads in IKE AUTH and INFORMATIONAL exchanges.
+	 */
+	GSList *local_ipv4_addresses;
+	GSList *local_ipv6_addresses;
+
+	GSList *local_ipv4_addresses_ptr;
+	GSList *local_ipv6_addresses_ptr;
+
+	/**
+	 * FIXME
+	 * If we are to switch to MOBIKE port (4500) to send IKE_AUTH and
+	 * it turns out that remote peer does not support MOBIKE for this
+	 * connection, we need to switch to ports set previously. That
+	 * could be IKEV2_PORT_NATT (4500), default port (500) as well as
+	 * any other set by any party
+	 */
+	 guint16 previous_port_i;
+	 guint16 previous_port_r;
 #endif /* MOBIKE */
 
 #ifdef CFG_CLIENT
@@ -537,19 +619,6 @@ struct session {
 	 * pass). This complicates code with many #ifdef's and if's.
 	 */
 	union sm_msg *embedded_sm_msg;
-
-	/**
-	 * FIXME
-	 * If we are to switch to MOBIKE port (4500) to send IKE_AUTH and
-	 * it turns out that remote peer does not support MOBIKE for this
-	 * connection, we need to switch to ports set previously. That
-	 * could be IKEV2_PORT_NATT (4500), default port (500) as well as
-	 * any other set by any party
-	 */
-#ifdef MOBIKE
-	 guint16 previous_port_i;
-	 guint16 previous_port_r;
-#endif /* MOBIKE */
 };
 
 /*******************************************************************************
@@ -661,6 +730,8 @@ struct sad_item *session_sad_item_find_by_msg_id(struct session *, guint32);
 int session_crypto_material(struct session *);
 
 gboolean session_use_radius(struct session *);
+
+GSList *session_add_peer_address(struct session *, struct netaddr *);
 /*******************************************************************************
  * DEBUG METHODS
  ******************************************************************************/
diff --git src/sm.c src/sm.c
index 25df5f2..368a00d 100644
--- src/sm.c
+++ src/sm.c
@@ -4420,7 +4420,7 @@ int sm_ike_i_thread(struct session *session, union sm_msg *sm_msg)
 		}
 
 		/*
-		 * Check if we received notify INVALID_SYNTAX. In that case
+		 * Check if we received notify NO_PROPOSAL_CHOSEN. In that case
 		 * terminate IKE SA..
 		 */
 		if (sm_msg->message_msg.ike_sa_init.no_proposal_chosen) {