Ethernet

Ethernet operates on a shared medium with multiple devices connected. To prevent signal jamming from different devices, Ethernet uses a protocol called CSMA/CD, which stands for Carrier Sense Multiple Access with Collision Detection. The CSMA/CD process occurs before and during the transmission of signals over the Ethernet cable and can be broken down into the following steps:

CSMA/CD Functions:

1) Check the sender's readiness to send packets.

2) Verify that the Ethernet cable is not in use by sending dummy data onto the medium. If the dummy data transmits without collision, the medium is considered idle. This is the carrier sense portion, where it senses for signals from other connected devices. If a collision occurs, it refrains and retries after a random time.

3) Transmit data and listen for collisions - At this point, data is transmitted, and the device listens for collision signals. If a collision occurs, it halts the transmission and emits a jam signal, instructing all devices using the medium to pause and retry after a random interval. Then, it restarts the process of sending a dummy signal.

4) If no signal collision is detected, the sender completes the frame transmission and prepares for the next transmission.

This protocol allows multiple devices to share a single communication medium effectively.