Hi Hunt, I did some research and found this:
Hello packets behave differently depending on the network type as described below. Point-to-point Network Neighbor discovery is dynamic Hello is sent to the multicast address AllSPFRouter (224.0.0.5) No DR/BDR election Broadcast Network Neighbor discovery is dynamic Hello is sent to the multicast address AllSPFRouter (224.0.0.5) DR/BDR election takes place NBMA Network A configuration is required in order to discover the neighbor Hello is sent unicast to each remote neighbor's IP address DR/BDR election takes place Note that since DR/BDR takes place, you would need at least a connection from DR/BDR to all the neighbors in order to guarantee the proper operation in this mode. DR/BDR sends Hello to all routers A router is eligible to become DR/BDR (priority different than 0) and it sends Hello packets only to DR/BDR and those routers that are eligible to become DR/BDR A router not eligible to become DR/BDR (priority 0) sends Hello packets only to DR/BDR Point-to-Multipoint Network Point-to-multipoint is considered a collection of point-to-point networks. Depending on the configuration, neighbor discovery could be dynamic. ip ospf network point-to-point Neighbor discovery is dynamic Hello is sent to the multicast address AllSPFRouter (224.0.0.5) No DR/BDR election In this case the Hello is sent to the multicast address AllSPFRouter and replicates the packet over each connection. It is important to note that the connection should be permanent (PVC) and not dynamic (SVC) as this would fail. ip ospf network point-to-multipoint non-broadcast A configuration is required in order to discover the neighbor Hello is unicast to each remote neighbor IP address Hope this helps. Regards, Georg Message Posted at: http://www.groupstudy.com/form/read.php?f=7&i=36377&t=36352 -------------------------------------------------- FAQ, list archives, and subscription info: http://www.groupstudy.com/list/cisco.html Report misconduct and Nondisclosure violations to [EMAIL PROTECTED]