diff --git a/infrastructure-centred/libowlps-client/libowlps-client.c b/infrastructure-centred/libowlps-client/libowlps-client.c
index 6a9eeb2..35ba713 100644
--- a/infrastructure-centred/libowlps-client/libowlps-client.c
+++ b/infrastructure-centred/libowlps-client/libowlps-client.c
@@ -79,9 +79,9 @@ void owlps_send_request(int sockfd, struct sockaddr_in *server,
 
 
 void owlps_send_packet(int sockfd, struct sockaddr_in *server,
-                       char *packet, int packet_size)
+                       void *packet, int packet_size)
 {
-  ssize_t nsent = sendto(sockfd, (void *) packet, packet_size, 0,
+  ssize_t nsent = sendto(sockfd, packet, packet_size, 0,
                          (struct sockaddr *) server,
                          (socklen_t) sizeof(*server)) ;
   if (nsent != (ssize_t) packet_size)
diff --git a/infrastructure-centred/libowlps-client/owlps-client.h b/infrastructure-centred/libowlps-client/owlps-client.h
index 0a4eca4..5616823 100644
--- a/infrastructure-centred/libowlps-client/owlps-client.h
+++ b/infrastructure-centred/libowlps-client/owlps-client.h
@@ -22,7 +22,7 @@ void owlps_send_request(int sockfd, struct sockaddr_in *server,
                         char *packet, int packet_size,
                         short nb_pkt, long delay) ;
 void owlps_send_packet(int sockfd, struct sockaddr_in *server,
-                       char *packet, int packet_size) ;
+                       void *packet, int packet_size) ;
 
 
 #endif // _LIBOWLPS_CLIENT_
diff --git a/infrastructure-centred/owlps-listener/owlps-listenerd.c b/infrastructure-centred/owlps-listener/owlps-listenerd.c
index e253bff..2544300 100644
--- a/infrastructure-centred/owlps-listener/owlps-listenerd.c
+++ b/infrastructure-centred/owlps-listener/owlps-listenerd.c
@@ -853,25 +853,23 @@ void autocalibrate_hello()
 {
   int send_sockfd ;
   struct sockaddr_in serv;
-  struct sockaddr_in client ;
-  socklen_t serv_len = sizeof(serv);
   autocalibration_hello message ;
 
 #ifdef DEBUG
   fprintf(stderr, "Autocalibration Hello thread launched.\n") ;
 #endif // DEBUG
 
-  send_sockfd = create_udp_sending_socket(GET_AGGREGATION_IP(),
-                                          GET_AUTOCALIBRATION_PORT(),
-                                          &serv, &client) ;
+  send_sockfd =
+    owlps_create_socket_to_aggregator(GET_AGGREGATION_IP(),
+                                      GET_AUTOCALIBRATION_PORT(),
+                                      &serv, GET_WIFI_IFACE()) ;
 
   memcpy(&message.ap_mac_addr_bytes, my_mac, 6) ;
   strncpy(message.ap_ip_addr, my_ip, 16) ;
 
   while (run)
     {
-      sendto(send_sockfd, (void *)&message, sizeof(message), 0,
-             (struct sockaddr *)&serv, serv_len) ;
+      owlps_send_packet(send_sockfd, &serv, &message, sizeof(message)) ;
       sleep(GET_AUTOCALIBRATION_HELLO_DELAY()) ;
     }