ARCHIVED: What is a broadcast or data storm?

A broadcast or data storm is excessive transmission of broadcast traffic in a network. This happens when a broadcast across a network results in even more responses, and each response results in still more responses, in a snowball effect. If network traffic reaches near 100% of the available bandwidth, all network traffic can be blocked.

Broadcast storms are often caused by a defective network adapter or defective cabling, where the card or cable floods the network with packets. This can be fixed quickly by disconnecting the computer system from the network and then replacing the Ethernet card, or by checking the network cable for any breaks, kinks, or loosened connectors, and then making repairs as needed. A broadcast storm can prevent access to server resources, or cause an entire network to go down.

Broadcast and data storms can also be caused by an intentional attack with the purpose of bringing down network systems. When this is the case, they are called distributed denial of service (DDoS) attacks. To prevent your computer from being a victim of or participant in a DDoS attack, make sure you have installed the latest security patches and have all your software up to date.

For information about protecting your computer at Indiana University, visit:

  http://itso.iu.edu/