Cisco Systems EA6500 Manual De Usuario

This chapter describes how to configure broadcast suppression on the Catalyst 6500 series switches. 
Releases earlier than Release 12.1(12c)E1 support broadcast suppression. Use traffic storm control with 
Release 12.1(12c)E1 and later releases (see 

).

For complete syntax and usage information for the commands used in this chapter, refer to the 
Catalyst 6500 Series Switch Cisco IOS Command Reference publication.

This chapter consists of these sections:

Broadcast suppression prevents LAN interfaces from being disrupted by a broadcast storm. A broadcast 
storm occurs when broadcast or multicast packets flood the subnet, creating excessive traffic and 
degrading network performance. Errors in the protocol-stack implementation or in the network 
configuration can cause a broadcast storm. 

Broadcast suppression uses filtering that measures broadcast activity in a subnet over a 1-second interval 
and compares the measurement with a predefined threshold. If the threshold is reached, further broadcast 
activity is suppressed for the duration the interval. Broadcast suppression is disabled by default.

 shows the broadcast traffic patterns on a LAN interface over a given interval. In this 

example, broadcast suppression occurs between times T1 and T2 and between T4 and T5. During those 
intervals, the amount of broadcast traffic exceeded the configured threshold.