Updating documentation
diff --git a/apps/ccnx-producer.cc b/apps/ccnx-producer.cc
index 0a101fd..6e413a0 100644
--- a/apps/ccnx-producer.cc
+++ b/apps/ccnx-producer.cc
@@ -46,6 +46,7 @@
 CcnxProducer::GetTypeId (void)
 {
   static TypeId tid = TypeId ("ns3::CcnxProducer")
+    .SetGroupName ("Ccnx")
     .SetParent<CcnxApp> ()
     .AddConstructor<CcnxProducer> ()
     .AddAttribute ("Prefix","Prefix, for which producer has the data",