CSMA/CD is a terminology used to define an intelligent way of sending data on a network known as Carrier Sense Multiple Access with Collision Detection. This method was popularly used in bus networks though currently, it is the application has reduced owing to better methods. In this method, a transmitting station checks whether the media for transmission is in use by another device. If so, it waits a random number of milliseconds before reattempting transmission. Immediately after a collision is detected, the device ends its transmission and waits before making a new attempt. It was found that this reduced the number of conflicts from a collision that resulted in the network.
The methods for collision detection depended on the media in use. Collisions could be detected by comparing sent data and received data or by the evidence of higher-than-normal signal strength on the medium. One disadvantage of this method is that when the load on the Ethernet is very high, some messages are likely to remain constantly locked out due to the algorithm. This would result in extremely long waiting periods for some devices, thus making accessibility an issue.