diff --git a/src/iface.h b/src/iface.h
index 863b5a4..be979b8 100644
--- a/src/iface.h
+++ b/src/iface.h
@@ -67,5 +67,17 @@ typedef struct MsgSpaceList {
   msgSpaceListElemId last;
 } msgSpaceList;
 
+typedef struct MsgQueueElem {
+  int poolIndex;
+  int bufferIndex;
+  msgQueueElemId next;  
+} msgQueueElem;
+
+typedef struct MsgQueue{
+  int elemCounter;
+  msgQueueElemId head; 
+  msgQueueElemId tail;
+} msgQueue;
+
 #endif
 /* */