ThinkerQAQ

1.Transport Layer

Computer Networks · 7 notes

  1. 1.1 TCP Three-Way Handshakehistorical

    How SYN, SYN-ACK, and ACK establish TCP state, synchronize initial sequence numbers, negotiate options, and protect against stale connection attempts.

  2. 1.2 TCP Connection Terminationhistorical

    TCP's independent half-close semantics, FIN/ACK exchange, FIN_WAIT/CLOSE_WAIT/LAST_ACK/TIME_WAIT states, and why termination is often illustrated with four segments.

  3. 1.3 TCP Flow Controlhistorical

    How TCP's receiver-advertised window prevents a fast sender from overrunning the receiver, including sliding windows, zero windows, and window scaling.

  4. 1.4 TCPhistorical

    TCP as a connection-oriented reliable byte-stream transport: sequencing, acknowledgements, retransmission, checksums, flow control, congestion control, and comparison with UDP.

  5. 1.5 TCP Keepalivehistorical

    TCP keepalive probes for detecting long-idle dead peers, and why application-level health checks often remain necessary in distributed systems.

  6. 1.6 TCP CLOSE_WAIThistorical

    What CLOSE_WAIT means, why it is a local application state after receiving FIN, and how persistent CLOSE_WAIT growth points to socket-lifecycle bugs.

  7. 1.7 TCP Congestion Controlhistorical

    TCP congestion windows, slow start, congestion avoidance, fast recovery, loss/ECN signals, and the distinction between classic Reno-style explanations and modern algorithms such as CUBIC and BBR.