diff --git a/core/net/rime/route-discovery.c b/core/net/rime/route-discovery.c
index 21afceaa9..4a471bbbc 100644
--- a/core/net/rime/route-discovery.c
+++ b/core/net/rime/route-discovery.c
@@ -271,14 +271,24 @@ static const struct unicast_callbacks rrep_callbacks = {rrep_packet_received};
 static const struct netflood_callbacks rreq_callbacks = {rreq_packet_received, NULL, NULL};
 /*---------------------------------------------------------------------------*/
 void
+route_discovery_expicit_open(struct route_discovery_conn *c,
+			     clock_time_t time,
+			     uint16_t netflood_channel,
+			     uint16_t unicast_channel,
+			     const struct route_discovery_callbacks *callbacks)
+{
+  netflood_open(&c->rreqconn, time, netflood_channel, &rreq_callbacks);
+  unicast_open(&c->rrepconn, unicast_channel, &rrep_callbacks);
+  c->cb = callbacks;
+}
+/*---------------------------------------------------------------------------*/
+void
 route_discovery_open(struct route_discovery_conn *c,
 		     clock_time_t time,
 		     uint16_t channels,
 		     const struct route_discovery_callbacks *callbacks)
 {
-  netflood_open(&c->rreqconn, time, channels + 0, &rreq_callbacks);
-  unicast_open(&c->rrepconn, channels + 1, &rrep_callbacks);
-  c->cb = callbacks;
+  route_discovery_expicit_open(c, time, channels + 0, channels + 1, callbacks);
 }
 /*---------------------------------------------------------------------------*/
 void
diff --git a/core/net/rime/route-discovery.h b/core/net/rime/route-discovery.h
index 81d454d5f..09ce984c2 100644
--- a/core/net/rime/route-discovery.h
+++ b/core/net/rime/route-discovery.h
@@ -83,6 +83,10 @@ struct route_discovery_conn {
 void route_discovery_open(struct route_discovery_conn *c, clock_time_t time,
 			  uint16_t channels,
 			  const struct route_discovery_callbacks *callbacks);
+void route_discovery_explicit_open(struct route_discovery_conn *c, clock_time_t time,
+				   uint16_t netflood_channel,
+				   uint16_t unicast_channel,
+				   const struct route_discovery_callbacks *callbacks);
 int route_discovery_discover(struct route_discovery_conn *c, const linkaddr_t *dest,
 			     clock_time_t timeout);