Basic concepts
A DCN network includes the following basic elements:
NE—A network device managed by the NMS on the DCN network.
GNE—The NE that is directly connected to the NMS. The NSM communicates with the GNE at the network layer or application layer and manages the NEs through the GNE.
NE table—Stores the NE ID-to-NE IP mappings for each NE in the DCN domain. After DCN is enabled, an NE encapsulates its NE ID and NE IP in a Type-10 Opaque LSA. It floods the LSA to synchronize the mappings with other NEs in the DCN domain. The NE IP in the Type-10 Opaque LSA might be inconsistent with the NE's router ID when DCN is enabled on an OSPF network. Devices from other vendors will fail to identify the NE. To avoid this problem, make sure the following requirements are met:
Change the router ID by modifying the NE IP. Do not change the default IP address of the DCN's loopback interface.
Do not associate other loopback interfaces to the DCN VPN instance.