Hello Daud,
1.) Is it possible that the 0.0.0.1 was actually the neighbor's Router ID? When starting OSPF on NBMA networks, it is sufficient to have a static neighbor defined just on one end of a VC - the other router will not be capable of initiating OSPF adjacency (because it does not know to whom it should initiate it) but once another router contacts it directly, it will respond and form an adjacency.
2.) Please include the configuration of your two routers. It is difficult to answer without knowing how your routers are exactly configured.
3.) If the broadcast network type is used, the router will indeed start using the multicast IP addresses 224.0.0.5 and 224.0.0.6 for OSPF communication. The Frame Relay is not capable of replicating these multicasts itself but if the IP/DLCI mappings are configured with the broadcast flag, your router will replicate each broadcast/multicast packet itself, sending it over every VC that has the broadcast flag set. Frame Relay does not really care if the packet is broadcast/multicast/unicast. All it cares about is whether the DLCI has been set properly.
This is a common confusion with NBMA networks, by the way. It is often believed that they are incapable of delivering broadcasts/multicasts. That is not true. They are incapable of replicating broadcasts/multicasts. It is the job of the node that is directly connected to a NBMA network to replicate such packets on its own, but after it has been replicated over every virtual circuit, the NBMA network will happily deliver it to the other end of the VC.
4.) The point-to-multipoint network type behaves, within the aspect of addressing, replicating and delivering multicast packets, exactly identically to the NBMA network type. Once again, there is no difference between PtMP and NBMA network types as far as the multicast packet replication/delivery goes.
The difference is in the way the OSPF models the network in its link-state database. With NBMA, the network itself is expected to provide full-mesh connectivity and is therefore represented as an LSA2 generated by the Designated Router - which has to be elected. If the NBMA network does not provide full-mesh connectivity then many things have to be tweaked: OSPF priorities for DR/BDR elections, next-hop address reachabilities, etc.
With PtMP, the network is seen simply as a bunch of VCs assorted under a common interface. There is no expectation of a full-mesh connectivity, quite contrary: a link is assumed between two routers only if they mutually hear and accept their Hello packets. If there is no VC between two routers, they won't hear themselves directly and hence, no direct connection between them will be installed in the link-state database. The PtMP does not elect DR/BDR and does not represent the network as a LSA-2. At a price of being more memory-intensive, it models the real reachability within the network far more accurately.
5.) The NBMA network type was put to OSPF primarily because OSPF was originally intended to run over networks with signalled VCs and each router could ask the network to provide a VC to every other router, creating a full mesh - think ATM, X.25, SMDS. A full mesh network is then representable more efficiently both in memory and CPU terms using a LSA-2.
However, with Frame Relay in particular, the network is seldom fully meshed. Much more often, Frame Relay networks are hub-and-spoke or partially meshed. The OSPF was never meant to run in NBMA mode on such networks and it is actually surprising how many people are trying to force the NBMA network type upon the Frame Relay. Frame Relay with its partially-meshed PVCs not controlled by individual routers is an exemplary candidate for Point-to-Multipoint network type. The downside of the PtMP network type is the increase in the memory and CPU complexity, because each router has to declare a link to all other routers it can hear Hello packets from, leading to O(N^2) memory complexity, as opposed to the linear O(N) complexity with LSA-2 and fully meshed networks.
Best regards,
Peter
