UGC NET CSE | December 2012 | Part 3 | Question: 4

Question

The technique of temporarily delaying outgoing acknowledgements so that they can be hooked onto the next outgoing data frame is known as

• A. Bit stuffing
• B. Piggy backing
• C. Pipelining
• D. Broadcasting

Answer 1

• Piggybacking of acknowledments:The ACK for the last received packet need not be sent as a new packet, but gets a free ride on the next outgoing data frame(using the ACK field in the frame header). The technique is temporarily delaying outgoing ACKs so that they can be hooked on the next outgoing data frame is known as piggybacking. But ACK can't be delayed for a long time if receiver(of the packet to be acknowledged) does not have any data to send.