What Is a UDP Flood?

The user datagram protocol (UDP) is a sessionless, or automatic, protocol that sends out packets, or groups of data. Protocols are sets of guidelines, or standards, that manage how data is transmitted over networks such as the Internet. The UDP protocol can be used to initiate a UDP flood attack.

Denial-of-Service

• A denial-of-service (DoS) attack refers to an attack on a network geared toward making system resources unavailable to intended users. A DoS attack involves prevention of a service or website from functioning properly. A UDP flood involves such an attack.

UDP Flood

• UDP flooding is an event that occurs when an attacker sends out Internet protocol (IP) packets containing UDP datagrams, or groups of data used in messaging, to random ports on a remote host. The host checks for appropriate applications listed at the port, determines no applications are listed and replies with a "Destination Unreachable" packet. Ultimately the host sends out so many packets that the system becomes flooded, and thus unattainable to other clients.

Firewalls

• UDP flooding can be prevented or managed via firewalls. Firewalls are system or network software designed to prevent unauthorized access while permitting authorized data transmissions. Firewalls can be positioned at key points in a system or network to filter out unwanted traffic.