diff --git a/src/Transport/EPTF_CLL_TransportIPL4_Functions.ttcn b/src/Transport/EPTF_CLL_TransportIPL4_Functions.ttcn
index e3a95a729770e22748760039829996bc1d61595e..484901b678eeab4780446d0ac5e60a7bba2fd7d4 100644
--- a/src/Transport/EPTF_CLL_TransportIPL4_Functions.ttcn
+++ b/src/Transport/EPTF_CLL_TransportIPL4_Functions.ttcn
@@ -70,6 +70,7 @@
 //      <f_EPTF_Transport_setUpInterfaces>
 //      <f_EPTF_Transport_appendInterfaces>
 //      <f_EPTF_Transport_setDownInterfaces>
+//      <f_EPTF_Transport_isConnIdValid>
 //      <f_EPTF_TransportIPL4_getConnectionDetails>
 //      <f_EPTF_TransportIPL4_activateDefaultBufferingHandler>
 //      <f_EPTF_TransportIPL4_portSend>
@@ -1443,6 +1444,28 @@ runs on EPTF_TransportIPL4_CT
   }
 }
 
+///////////////////////////////////////////////////////////
+//  Function: f_EPTF_Transport_isConnIdValid
+// 
+//  Purpose:
+//    Function to get whether a connection ID is valid/allocated
+//
+//  Parameters:
+//    pl_connId - *in* *integer* - connection ID
+//
+//  Return Value:
+//    *boolean* - true if the connection ID is valid
+//
+///////////////////////////////////////////////////////////
+public function f_EPTF_Transport_isConnIdValid(
+  in integer pl_connId)
+runs on EPTF_TransportIPL4_CT
+return boolean
+{
+  var integer vl_connInfofbqId;
+  return f_EPTF_int2int_HashMap_Find(v_EPTF_TransportIPL4_connInfoHashMapId,pl_connId,vl_connInfofbqId);
+}
+
 ///////////////////////////////////////////////////////////
 //  Function: f_EPTF_TransportIPL4_getConnectionDetails
 //