MSFC2 has a feature called broadcast suppression to control the broadcasts.
Broadcast Suppression prevents switched ports on a LAN from being disrupted by a broadcast storm on one of the ports. A LAN broadcast storm occurs when broadcast or multicast packets flood the LAN, creating excessive traffic and degrading network performance. Broadcast suppression uses filtering that measures broadcast activity on a LAN over a one second time and is implemented in hardware. The suppression circuitry on a line card monitors packets passing from a port to the switching bus using the Group/Individual bit in a frame. It keeps track of the current count of broadcasts within the one-second-time interval, and when the threshold percentage is reached, filters out subsequent broadcast packets.
You can also use helper addresses to control broadcasts in an IPX network and Appletalk network.
See the following URLs for additional information.
http://www.cisco.com/en/US/products/sw/iosswrel/ps1835/products_configuration_guide_chapter09186a0080080f3d.html#xtocid31
http://www.cisco.com/en/US/products/hw/switches/ps708/products_white_paper09186a008009d846.shtml
