diff --git a/src/http.h b/src/http.h
index 7f26148..b045205 100644
--- a/src/http.h
+++ b/src/http.h
@@ -136,6 +136,7 @@ typedef struct http_connection {
   char *hc_peer_ipstr;
   struct sockaddr_storage *hc_self;
   char *hc_representative;
+  int is_local_address_cache;

   pthread_mutex_t  *hc_paths_mutex;
   http_path_list_t *hc_paths;
diff --git a/src/satip/rtsp.c b/src/satip/rtsp.c
index bd8c978..f8cb68c 100644
--- a/src/satip/rtsp.c
+++ b/src/satip/rtsp.c
@@ -322,14 +322,18 @@ static inline const char *
 rtsp_conn_ip(http_connection_t *hc, char *buf, size_t buflen, int *port)
 {
   const char *used_ip = rtsp_ip;
-  int used_port = rtsp_port, local;
+  int used_port = rtsp_port;
+  int local = hc->is_local_address_cache;
   struct sockaddr_storage self;

   if (rtsp_nat_ip[0] == '\0')
     goto end;
   self = *hc->hc_self;
   /* note: call ip_check at first to initialize self (ip any) */
-  local = ip_check_is_local_address(hc->hc_peer, hc->hc_self, &self);
+  if (local < 0) {
+    hc->is_local_address_cache = ip_check_is_local_address(hc->hc_peer, hc->hc_self, &self);
+    local = hc->is_local_address_cache;
+  }
   if (local || satip_server_conf.satip_nat_name_force) {
     used_ip = rtsp_nat_ip;
     if (rtsp_nat_port > 0)
@@ -1664,6 +1668,7 @@ rtsp_serve(int fd, void **opaque, struct sockaddr_storage *peer,
   hc.hc_self    = self;
   hc.hc_process = rtsp_process_request;
   hc.hc_cseq    = 1;
+  hc.is_local_address_cache = -1;

   http_serve_requests(&hc);