9. TCP . TCP

9. TCP Reliable Protocol Infallible Protocol .

TCP , Effective TCP/IP ProgrammingBy Jon C. Snader

TCP .TCP . TCP .

TCP

TCP end-to-end . ,End end .

! end TCP .A B .

TCP Network Outage( )Peer Application CrashPeer Host Crash

1.Network OutageEnd point

ICMP .

End point( TCP) TCP .

2. Peer Application CrashPeer Application Crash FIN . Peer Peer close .FIN close . RST .

ClientServer

1. FIN

2. Left data

3. RST

Application FIN

1. send TCP TCP ACK readline send TCP TCP TCP FIN readline FIN fgets , TCP FIN ACK close FIN . FIN close . send TCP . TCP RST readline close .

2. send TCP TCP ACK TCP FIN readline close .

? Application

.

3. Peer Host CrashPeer TCP FIN .Peer .TCP . , TIMEOUT . TCP RST .

ClientSever

1. TIMEOUT

2. -> RST

TCP .TCP .