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Basically, the CSMA/CD algorithm can be summarized as follows:

• A device that wants to send a frame waits until the LAN is silent – in other words, no frames are currently being sent – before attempting to send an electrical signal.

• If a collision still occurs, the devices that caused the colision wait a random amuont of time and then try again.

CSMA/CD logic help prevent collisions and also defines how to act when a coolision does occur. The CSMA/CD algorithm works like this:

Step 1: A device with a frames to send listens until the Ethernet is not busy.

Step 2: When the Ethernet is not busy, the sender(s) begin(s) sending the frame.

Step 3: The sender(s) listen(s) to make sure that no collision occurred.

Step 4: If a collision occurrs, the devices that had been sending a frame each send a jamming signal to ensure that all stations recognize the collision.

Step 5: After the jamming in complete, each sender randomizes a timer and waits that long before trying to resend the collided frame.

Step 6: When each random timer expires, the process starts over with Step 1.