CSMA/CD and Ethernet Two way cable wsws Ws W CSMA with Collision Detection(CD)capability Nodes able to detect collisions Upon detection of a collision nodes stop transmission Reduce the amount of time wasted on collisions Protocol All nodes listen to transmissions on the channel When a node has a packet to send Channel idle => Transmit Channel busy = wait a random delay (binary exponential backoff) If a transmitting node detects a collision it stops transmission Eytan Modiano Waits a random delay and tries againCSMA/CD and Ethernet Two way cable WS WS WS WS WS WS • CSMA with Collision Detection (CD) capability – Nodes able to detect collisions – Upon detection of a collision nodes stop transmission Reduce the amount of time wasted on collisions • Protocol: – All nodes listen to transmissions on the channel – When a node has a packet to send: Channel idle => Transmit Channel busy => wait a random delay (binary exponential backoff) – If a transmitting node detects a collision it stops transmission Slide 2 Eytan Modiano Waits a random delay and tries again