:
1. TCP , . SYN, , 1 - SYN-. SYN-, IP- .
2. IP- SYN- , SYN-, , , TCP-. SYN = 1, +1 - . - SYNACK - .
3. SYNACK - , , SYNACK - - +1, SYN=0.
.
: , , FIN=1. , , FIN=1, .
TCP- TCP-.
CLOSED ( TCP- ( , SYN-)) => SYN_SENT ( SYNACK-) => ESTABLISHED ( ) => FIN_WAIT_1 ( FIN=1, ) => FIN_WAIT_2 ( , FIN=1) => TIME_WAIT ( , , ( ( )) => ( ).
: CLOSED => => LISTEN => SYN, SYN ACK => SYN_RCVD => ACK, => ESTABLISHED ( ) => ( FIN, ACK) CLOSE_WAIT => FIN => LAST_ACK => ACK, .
32- .
16- (- , . )
4- TCP- 32- . TCP- ( , 20 )
, , , - - .
6 : (ACK) , , , . RST, SYN FIN . PSH , . URG , , .
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: TCP-, . TCP => , . . , , - , . TCP - . : 1) , 2) , .
TCP .
: (SampleRTT) - , , 1 , , 1 , . SampleRTT - EstimatedRTT.
EstimatedRTT = (1-a)*EstimatedRTT + a*SampleRTT ( = 0,125)
- SampleRTT - .
DevRTT - SampleRTT EstimatedRTT.
:
TimeoutInterval = EstimatedRTT + 4*DevRTT.
: .