Identify Neighbor Gateways

This section only applies if one of the nodes on your network is a gateway. A neighbor gateway is a gateway that is on the same network as a given node. A non-gateway node on a network may need to go through a neighbor gateway in order to send messages to an entirely different network. Two nodes are on the same network if the network portion of their IP addresses are the same. All X.25 nodes on the same network need to know the identities of any accessible neighbor gateways. Therefore, when using NMMGR to configure any node, you will be entering the identities of all the neighbor gateways into the configuration of the node. Following is an example:

Example: Identifying Neighbor Gateways of Node B

In Figure 5-3 “Identifying Neighbor Gateways of Node B”, Net 1 is a LAN, Net 2 is an X.25 network, and Net 3 is a point-to- point network. Node A is on both Net 1 and Net 2 and is a full gateway between them. Node A is the Neighbor Gateway for all nodes on Net 1 to reach Net 2. Node C is on Net 1 and Net 3 and is a gateway half. Node C is the Neighbor Gateway for all nodes on Net 1 to reach Net 3.

If you were configuring a node such as Node B in Figure 5-3 “Identifying Neighbor Gateways of Node B”, you would enter the identities of Nodes A and C as neighbor gateways of Node B (at the Neighbor Gateways screen and the Neighbor Gateway Reachable Networks screen). On the Neighbor Gateway Reachable Networks screen, you would also enter the IP address of Network 2 as a Configured Reachable Network reachable through gateway Node A and the IP address of Network 3 as a Configured Reachable Network reachable through gateway Node C.

Figure 5-3 Identifying Neighbor Gateways of Node B