Build a Reliable Transport Layer

sequence numbers, acks, sliding window

Challenge 6 of Networking & ProtocolsAdvanced~60 min

Build reliable delivery on top of an unreliable network, the problem TCP solves. Packets get lost, duplicated, and reordered; the transport layer hides all of it. Implement sequence numbers, a receiver that reassembles in order with cumulative acknowledgements, a sender that tracks what's been acked, and a sliding window with retransmission. The machinery that turns a lossy channel into an ordered, gap-free byte stream.

4 steps

1. 1Sequence Numbers
2. 2Cumulative Acknowledgements
3. 3Tracking Acknowledgements
4. 4Sliding Window and Retransmission