Chapter 5 Configuring Bridging; Bridging - Cisco ONS 15454 Software Feature And Configuration Manual

5
Configuring Bridging
This chapter describes how to configure bridging for the ML-Series card. For more information about
the Cisco IOS commands used in this chapter, refer to the Cisco IOS Command Reference publication.
This chapter includes the following major sections:
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Cisco Inter-Switch Link (ISL) and Cisco Dynamic Trunking Protocol (DTP) are not supported by the
Caution
ML-Series, but the ML-Series broadcast forwards these formats. Using ISL or DTP on connecting
devices is not recommended. Some Cisco devices attempt to use ISL or DTP by default.

Bridging

The ML-Series card can be configured to serve as an IP router and a bridge. Cisco IOS software supports
transparent bridging for Fast Ethernet, Gigabit Ethernet, and POS. Cisco IOS software functionality
combines the advantages of a spanning-tree bridge and a router. This combination provides the speed
and protocol transparency of a spanning-tree bridge, along with the functionality, reliability, and security
of a router.
To configure bridging, you must perform the following tasks in the modes indicated:
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Cisco ONS 15454 SONET/SDH ML-Series Multilayer Ethernet Card Software Feature and Configuration Guide, R4.0
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Bridging, page 5-1
Configuring Bridging Example, page 5-3
Monitoring and Verifying Bridging, page 5-4
In global configuration mode:
Enable bridging of IP packets.
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– Select the type of Spanning Tree Protocol.
In interface configuration mode:
– Determine which interfaces belong to the same bridge group.
These interfaces become part of the same spanning tree, allowing the ML-Series card to bridge
all nonrouted traffic among the network interfaces comprising the bridge group. Interfaces not
participating in a bridge group cannot forward bridged traffic.
C H A P T E R
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