CSMA/CD

CSMA/CD

1. Carrier Sense Multiple Access with Collision Detection

2. Host checks for the presence of a digital signal on the wire.

3. When a collision occurs:

   • 1. A jam signal informs all devices that a collision occured.
   • 2. The collision invokes a random backoff alorithm
   • 3. Each device on the Ethernet segment stops transmitting for a short time until its backoff time expires.
   • 4. All hosts have equal priority to transmit after the timers have expired.

4. Effects include delay, low throughput and congestion.