TCP

• 文獻

  [http:\/\/www.ietf.org\/](http://www.ietf.org/)
  

• seq number 和 acknologement 的關係

  seq number 表示這次送出去封包的 id
  ack number 表示回應的封包 id
  

• Acknowledgment Number: 32 bits

    If the ACK control bit is set this field contains the value of the
    next sequence number the sender of the segment is expecting to
    receive.  Once a connection is established this is always sent.
  

• icmp

  http:\/\/godleon.blogspot.tw\/2008\/01\/icmpinternet-control-message-protocol.html