diff --git a/TODO b/TODO
index 7113069..04cd247 100644
--- a/TODO
+++ b/TODO
@@ -1,8 +1,5 @@
 * Global
 
-- Fix endianess issues
-   Check carefully the network exchanges to track every non-conversion
-   of endianess.
 - Mark arguments as const in function headers if needed
    That is done in the owlps-positioning C++ code, but not constantly
    in C modules.
diff --git a/infrastructure-centred/owlps-aggregator/owlps-aggregatord.c b/infrastructure-centred/owlps-aggregator/owlps-aggregatord.c
index e50e474..0b04b67 100644
--- a/infrastructure-centred/owlps-aggregator/owlps-aggregatord.c
+++ b/infrastructure-centred/owlps-aggregator/owlps-aggregatord.c
@@ -349,6 +349,10 @@ int read_loop(int sockfd)
           break ;
         }
 
+      // Endianess conversions:
+      message.request_time = owl_ntoh_timestamp(message.request_time) ;
+      message.start_time = owl_ntoh_timestamp(message.start_time) ;
+
       if (cfg_getbool(cfg, "verbose"))
         {
           ap_mac_str =
@@ -503,12 +507,18 @@ void* monitor_couples()
                   demande.request_time = couple_ptr->request_time ;
                   demande.nb_couples = 0 ;
 
+                  // Count the couples:
                   couple_info_ptr = couple_ptr->info ;
                   while (couple_info_ptr != NULL)
                     {
                       demande.nb_couples++;
                       couple_info_ptr = couple_info_ptr->next ;
                     }
+                  // Endianess conversions:
+                  demande.nb_couples = htons(demande.nb_couples) ;
+                  demande.request_time =
+                    owl_hton_timestamp(demande.request_time) ;
+                  // Send the request:
                   sendto(sockfd, (void *)&demande, sizeof(request), 0,
                          (struct sockaddr *)&serv, serv_len) ;
 
@@ -1006,7 +1016,7 @@ void order_send(ap_list *ap)
                               cfg_getint(cfg, "autocalibration_port"),
                               &serv, &client) ;
 
-  message.order = htonl(AUTOCALIBRATION_ORDER_SEND) ;
+  message.order = AUTOCALIBRATION_ORDER_SEND ;
   nsent = sendto(sockfd, (void *)&message, sizeof(message), 0,
                  (struct sockaddr *)&serv, serv_len) ;
   if (nsent != (ssize_t) sizeof(message))
diff --git a/infrastructure-centred/owlps-client/owlps-client.c b/infrastructure-centred/owlps-client/owlps-client.c
index b126cd3..333eed4 100644
--- a/infrastructure-centred/owlps-client/owlps-client.c
+++ b/infrastructure-centred/owlps-client/owlps-client.c
@@ -305,6 +305,8 @@ void make_packet()
   TIMESTAMP request_time ;
   char request_time_str[TIMESTAMP_STR_LEN] ;
 
+  // Get the current time and copy it as a string before to switch it to
+  // network endianess:
   owl_timestamp_now(&request_time) ;
   owl_timestamp_to_string(request_time_str, request_time) ;
   request_time = owl_hton_timestamp(request_time) ;
diff --git a/infrastructure-centred/owlps-listener/owlps-listenerd.c b/infrastructure-centred/owlps-listener/owlps-listenerd.c
index 79d0db5..9e6f61a 100644
--- a/infrastructure-centred/owlps-listener/owlps-listenerd.c
+++ b/infrastructure-centred/owlps-listener/owlps-listenerd.c
@@ -618,6 +618,8 @@ void read_packet(u_char *args, const struct pcap_pkthdr *header,
 
   if (GET_MODE() != MODE_PASSIVE) // If mode is active or mixed
     {
+      uint_fast16_t dest_port ;
+
       // Protocol for an explicit request is UDP
       if (packet_ip_header->protocol != IPPROTO_UDP)
         goto not_explicit_packet ;
@@ -626,12 +628,13 @@ void read_packet(u_char *args, const struct pcap_pkthdr *header,
       packet_udp_header = (struct udphdr *)
         &packet[rtap_bytes + ieee80211_header_size +
                 LLC_HEADER_SIZE + sizeof(struct iphdr)] ;
+      dest_port = ntohs(packet_udp_header->dest) ;
 
-      if (GET_AUTOCALIBRATION() && ntohs(packet_udp_header->dest) ==
-          GET_AUTOCALIBRATION_REQUEST_PORT())
+      if (GET_AUTOCALIBRATION() && dest_port ==
+          (uint_fast16_t) GET_AUTOCALIBRATION_REQUEST_PORT())
         uses_autocalibration_request_port = TRUE ;
 
-      else if (ntohs(packet_udp_header->dest) != GET_LISTENING_PORT())
+      else if (dest_port != (uint_fast16_t) GET_LISTENING_PORT())
         goto not_explicit_packet ;
     }
 
@@ -660,7 +663,7 @@ void read_packet(u_char *args, const struct pcap_pkthdr *header,
     return ;
 
   memcpy(couple.ap_mac_addr_bytes, my_mac_bytes, 6) ; // Copy AP MAC
-  // Capture time is in the pcap header:
+  // Capture time is in the pcap header (net-endian):
   couple.start_time = owl_timeval_to_timestamp(header->ts) ;
   // Transmission time on the mobile is unknown (unless the packet is
   // an explicit request):
@@ -734,6 +737,8 @@ void read_packet(u_char *args, const struct pcap_pkthdr *header,
                    " an implicit one.\n") ;
         }
       else
+        // Copy the timestamp "as is" (i.e. without changing endianess)
+        // because it will return to the network soon:
         memcpy(&couple.request_time,
                &packet[rtap_bytes + ieee80211_header_size +
                        LLC_HEADER_SIZE + sizeof(struct iphdr) +
@@ -851,8 +856,10 @@ void read_packet(u_char *args, const struct pcap_pkthdr *header,
       char
         request_time_str[TIMESTAMP_STR_LEN],
         start_time_str[TIMESTAMP_STR_LEN] ;
-      owl_timestamp_to_string(request_time_str, couple.request_time) ;
-      owl_timestamp_to_string(start_time_str, couple.start_time) ;
+      owl_timestamp_to_string(request_time_str,
+                              owl_ntoh_timestamp(couple.request_time)) ;
+      owl_timestamp_to_string(start_time_str,
+                              owl_ntoh_timestamp(couple.start_time)) ;
       printf("*** Couple to send ***\n"
              "\tMAC AP: %s\n"
              "\tMobile MAC: %s\n"
@@ -1019,7 +1026,7 @@ void autocalibrate()
           continue ;
         }
 
-      if (ntohl(message.order) == AUTOCALIBRATION_ORDER_SEND)
+      if (message.order == AUTOCALIBRATION_ORDER_SEND)
         {
           if (GET_VERBOSE())
             fprintf(stderr, "I was just ordered to send an"
@@ -1072,6 +1079,8 @@ uint_fast16_t make_packet(uint8_t **packet)
       printf("Autocalibration time: %s\n", request_time_str) ;
     }
 
+  request_time = owl_hton_timestamp(request_time) ;
+
   size = sizeof(char) + sizeof(TIMESTAMP) ;
   pkt = malloc(size) ;
 
diff --git a/libowlps/owlps.h b/libowlps/owlps.h
index 0c01cda..4823f6a 100644
--- a/libowlps/owlps.h
+++ b/libowlps/owlps.h
@@ -57,7 +57,8 @@ typedef enum {FALSE, TRUE} BOOL ;
 
 
 /* Direction type */
-typedef enum {NORTH = 1, EAST, SOUTH, WEST} DIRECTION ;
+enum {NORTH = 1, EAST, SOUTH, WEST} ;
+typedef uint8_t DIRECTION ;
 
 
 /* Timestamp type (struct timespec clone with fix-sized fields) */
@@ -96,7 +97,7 @@ typedef struct _request
 {
   uint8_t mobile_mac_addr_bytes[6]; // MAC of the mobile
   TIMESTAMP request_time ; // Request ID (timestamp on the mobile)
-  int nb_couples; // Number of (listener MAC;signal strength) couples
+  uint16_t nb_couples; // Number of (listener MAC;signal strength) couples
 } request;
 
 /* Hello message sent by the listener to the aggregator */
@@ -106,9 +107,10 @@ typedef struct _autocalibration_hello
 } autocalibration_hello ;
 
 /* Message sent to the listener to order an emission */
+#define AUTOCALIBRATION_ORDER_SEND 1
 typedef struct _autocalibration_order
 {
-  enum {AUTOCALIBRATION_ORDER_SEND = 1} order ;
+  uint8_t order ;
 } autocalibration_order ;
 
 /* Positioning request types */