diff --git a/include/villas/node.h b/include/villas/node.h
index 7cb8394db..7c09de010 100644
--- a/include/villas/node.h
+++ b/include/villas/node.h
@@ -50,6 +50,8 @@ struct node
 
 	qptr_t sent;		/**< Number of samples sent / written to this node. */
 	qptr_t received;	/**< Number of samples received / read from this node. */
+	
+	qptr_t seq_num;		/**< Manual sequence number in case a node doesn't support it. */
 
 	enum node_state {
 		NODE_INVALID,	/**< This node object is not in a valid state. */
diff --git a/lib/hooks/hooks-internal.c b/lib/hooks/hooks-internal.c
index f260e0a73..26958703c 100644
--- a/lib/hooks/hooks-internal.c
+++ b/lib/hooks/hooks-internal.c
@@ -67,10 +67,6 @@ int hook_drop(struct path *p, struct hook *h, int when, struct sample *smps[], s
 {
 	int i, ok, dist;
 
-	/** Don't check the sequence number order in case of gtnet-skt without header */
-	if(!strcmp(p->in->_vt->name, "socket") && !GTNET_SKT_HEADER)
-		return cnt;
-
 	for (i = 0, ok = 0; i < cnt; i++) {
 		h->last = smps[i];
 		
diff --git a/lib/node.c b/lib/node.c
index 7baa1a407..dca14ae83 100644
--- a/lib/node.c
+++ b/lib/node.c
@@ -113,6 +113,8 @@ int node_start(struct node *n)
 	if (ret == 0)
 		n->state = NODE_RUNNING;
 	
+	n->seq_num = 0; /** @todo is it the appropriate place to initialize seq_num? */
+	
 	return ret;
 }
 
diff --git a/lib/nodes/socket.c b/lib/nodes/socket.c
index f6c3e3f12..ecffea3c7 100644
--- a/lib/nodes/socket.c
+++ b/lib/nodes/socket.c
@@ -276,7 +276,7 @@ int socket_read(struct node *n, struct sample *smps[], unsigned cnt)
 		smp->ts.origin.tv_sec  = header[1];
 		smp->ts.origin.tv_nsec = header[2];
 #else
-		smp->sequence = -1;
+		smp->sequence = n->seq_num++;
 		smp->ts.origin.tv_sec = -1;
 		smp->ts.origin.tv_nsec = -1;
 #endif