TCP .
: (SampleRTT) - , , 1 , , 1 , . SampleRTT - EstimatedRTT.
EstimatedRTT = (1-a)*EstimatedRTT + a*SampleRTT ( = 0,125)
- SampleRTT - .
DevRTT - SampleRTT EstimatedRTT.
DevRTT = (1-b)*DevRTT + b*|SampleRTT - EstimatedRTT|
b = 0.25
:
TimeoutInterval = EstimatedRTT + 4*DevRTT.
: TCP . EstimatedRTT DevRTT TCP . ( ).
: - , , . 3 , . TCP .
N : TCP , , . . TCP , . TCP , , , .
: , .. -, . , .
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: - , , . 3 , . TCP .
N : TCP , , . . TCP , . TCP , , , .
: TCP-, . . , . TCP , , . - . TCP , , .
TCP.
TCP-, . . , . TCP , , . - . TCP , , , RcvBuffer.
LastByteRead - , .
LastByteRcvd - , .
, : LastByteRcvd - LastByteRead <= RcvBuffer.
RcvWindow :
RcvWindoq = RcvBuffer - [LastByteRcvd - LastByteRead]
.
: , RcvWindow , . RcvWindoq = RcvBuffer.
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2 LastByteSent LastByteAcked - . LastByteSent - LastByteAcked - , .
LastByteSent LastByteAcked <= RcvWindow
, .
: , , RcvWindow = 0, , , . , 1 , , , RcvWindow .