Zhone Technologies 800, 900, 600 manual Hub-and-Spoke, IPR WAN Routing IPR Card

IPR WAN Routing IPR Card

8.4IPR WAN Routing

IPR is designed to provide a maximum level of flexibility to users with different IP WAN topology requirements. IPR supports hub-and-spoke topology, partially or fully meshed topology, point-to-point IP interfaces, multi-point IP interface, unnumbered IP interfaces or a combination of any of the above. Figure 8-4shows the Hub-to-Spoke Topology.

8.4.1Hub-and-Spoke

The Hub-and-Spoke topology is that every “regional” (spoke) router has to go through the same “central-office: (hub) router for every destination IP node that is not local to a spoke router. This topology is very simple to configure: All spoke routers have a hub router as their default gateway (Default gateway is a router that IP nodes go to if they do not know a path to a particular IP network). Hub can be completely passive (from a routing protocol point of view), advertising no routes to spoke router, and the spoke router can be configured with default point at the hub. A spoke router, in its turn, will advertise any locally known or discovered IP networks (if any) through any routing protocol, since routing convergence time is irrelevant. IPR can be both a spoke and/or a hub router.

"Spoke" Router "Spoke" Router

Central Side

"Hub" Router

"Spoke" Router "Spoke" Router

Figure 8-4. Hub-and-Spoke Topology

8-6 Server Cards