associate using the username and source as a more reliable key

kamailio/default.cfg

@@ -835,9 +835,9 @@ route[INTERNAL_REDIRECT]
 
 onsend_route {
     if (isflagset(FLAG_ASSOCIATE_USER)) {
-        $var(contact_uri) = $(ct{tobody.user}) + "@" + $(ct{tobody.host});
-        xlog("L_INFO", "$ci|log|associate user $var(contact_uri) with media server sip:$sndto(ip):$sndto(port)\n");
-        $sht(associations=>$var(contact_uri))= "sip:" + $sndto(ip) + ":" + $sndto(port);
+        $var(user_source) = $(ct{tobody.user}) + "@" + $si + ":" + $sp;
+        xlog("L_INFO", "$ci|log|associate traffic from $var(user_source) with media server sip:$sndto(ip):$sndto(port)\n");
+        $sht(associations=>$var(user_source))= "sip:" + $sndto(ip) + ":" + $sndto(port);
     }
 
     xlog("L_INFO", "$ci|pass|$sndfrom(ip):$sndfrom(port) -> $sndto(ip):$sndto(port)\n");

kamailio/dispatcher-role.cfg

@@ -92,7 +92,7 @@ route[DISPATCHER_FIND_ROUTES]
         }
     }
 
-    $var(contact_uri) = $(ct{tobody.user}) + "@" + $(ct{tobody.host});
+    $var(user_source) = $(ct{tobody.user}) + "@" + $si + ":" + $sp;
     $var(redirect) = @from.uri.user + "@" + @from.uri.host + "->"
         + @ruri.user + "@" + @ruri.host;
     if ($sht(redirects=>$var(redirect)) != $null) {
@@ -101,9 +101,9 @@ route[DISPATCHER_FIND_ROUTES]
         if (route(DISPATCHER_REORDER_ROUTES)) {
             $avp(AVP_REDIRECT_KEY) = $var(redirect);
         }
-    } else if ($sht(associations=>$var(contact_uri)) != $null) {
-        $var(prefered_route) = $sht(associations=>$var(contact_uri));
-        xlog("L_INFO", "$ci|log|found association for contact uri $var(contact_uri)\n");
+    } else if ($sht(associations=>$var(user_source)) != $null) {
+        $var(prefered_route) = $sht(associations=>$var(user_source));
+        xlog("L_INFO", "$ci|log|found association for contact uri $var(user_source)\n");
         if (!route(DISPATCHER_REORDER_ROUTES)) {
             $sht(associations=>$var(association)) = $null;
         }