Cisco Systems 8600 Series manual Tiered Networks, Routing Hubs and Interface Shelves

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Tiered Networks

This chapter describes the tiered network architecture that supports interface shelves (non-routing nodes) connected to an IPX/IGX/BPX routing network.

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Routing Hubs and Interface Shelves

BPX Routing Hubs in a Tiered Network

IGX Routing Hubs in a Tiered Network

User Interface Commands

Cisco StrataView Plus NMS

With Release 8.5, tiered networks now support voice and data connections as well as frame relay connections. With this addition, a tiered network can now provide a multi-service capability (frame relay, circuit data, voice, and ATM). By allowing CPE connections to connect to a non-routing node (interface shelf), a tiered network is able to grow in size beyond that which would be possible with only routing nodes comprising the network.

Routing Hubs and Interface Shelves

In a tiered network, interface shelves at the access layer (edge) of the network are connected to routing nodes via feeder trunks (Figure 13-1). Those routing nodes with attached interface shelves are referred to as routing hubs. The interface shelves, sometimes referred to as feeders, are non-routing nodes. The routing hubs route the interface shelf connections across the core layer of the network.

The interface shelves do not need to maintain network topology nor connection routing information. This task is left to their routing hubs. This architecture provides an expanded network consisting of a number of non-routing nodes (interface shelves) at the edge of the network that are connected to the network by their routing hubs.

BPX and IGX Routing Hubs

Voice and data connections originating and terminating on IGX interface shelves (feeders) are routed across the routing network via their associated IGX routing hubs. Intermediate routing nodes must be IGX nodes.

Tiered Networks 13-1