Cisco Systems BC-109 manual Configure Fast-Switching SRB over FDDI, Configure SRB over Frame Relay

Configure Source-Route Bridging

Configure Fast-Switching SRB over FDDI

Fast-Switching SRB over FDDI enhances performance. For example, if you want to use access-lists, fast-switching SRB over FDDI provides fast performance and access-list filters capability.

To configure fast-switching SRB over FDDI, use the following commands, beginning in global configuration mode:

Step	Command	Purpose
1	interface fddi slot/port	Configure an FDDI interface.
2	source-bridgelocal-ring bridge-number	Enable source-route bridging.
	target-ring
3	source-bridge spanning	Enable source-bridge spanning.
4	source-bridge route-cache	Enable fast-switching.
5	multiring protocol-keyword	Enable the collection and use of RIF
		information.

Configure SRB over Frame Relay

Cisco IOS software offers the ability to encapsulate source-route bridging traffic using RFC 1490 Bridged 802.5 encapsulation. This provides SRB over Frame Relay functionality that is interoperable with other vendors’ implementations of SRB over Frame Relay and with some vendors’ implementations of FRAS BAN.

Note In the initial release, SRB over Frame Relay does not support the Cisco IOS software proxy explorer, automatic spanning-tree, or LAN Network Manager functions.

To configure SRB over Frame Relay, use the following commands in interface configuration mode:

Step	Command	Purpose
1	interface serial number	Specify the serial port.
2	encapsulation frame-relay	Enable Frame Relay encapsulation.
3	interface serial slot/port.subinterface-number	Configure a Frame Relay
	point-to-point	point-to-point subinterface.
4	frame-relay interface-dlci dlci ietf	Configure a DLCI number for the
		point-to-point subinterface.
5	source-bridgesource-ring-number bridge-number	Assign a ring number to the Frame
	target-ring-number conserve-ring	Relay permanent virtual circuit.

Enable the Forwarding and Blocking of Spanning-Tree Explorers

When trying to determine the location of remote destinations on a source-route bridge, the source device will need to send explorer packets. Explorer packets are used to collect routing information field (RIF) information. The source device can send spanning-tree explorers or all-routes explorers. Note that some older IBM devices generate only all-routes explorer packets, but many newer IBM devices are capable of generating spanning-tree explorer packets.

A spanning-tree explorer packet is an explorer packet that is sent to a defined group of nodes that comprise a statically configured spanning tree in the network. In contrast, an all-routes explorer packet is an explorer packet that is sent to every node in the network on every path.

BC-114Bridging and IBM Networking Configuration Guide