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传输控制协议
传输控制协议在不可靠的数据报服务之上，为互联网中任意两个进程之间建立可靠、有序的字节流；连接由端口与地址构成的四元组命名，并通过三次握手开启，该握手同步序号以防范早已失效的重复报文；链路层的滑动窗口再次出现，但以字节为单位度量，并受接收方通告窗口的限制，从而使慢速接收方绝不会被淹没；糊涂窗口病态通过等待完整报文段或可用确认的规则加以抑制；重传计时器适应往返时间达两个数量级的变化，估计平滑平均值及其方差，并拒绝采样被重传所污染的计时样本。
1. A Byte Stream from Datagrams
A Byte Stream from Datagrams
2. The Three-Way Handshake
The Three-Way Handshake
3. The Window, Measured in Bytes
The Window, Measured in Bytes
4. Guessing the Round Trip
Guessing the Round Trip
5. What the stream hides
An application writes 2000 bytes in one call, then 100 bytes in another. What does the receiving application see?
6. Why three messages
Why does TCP's connection setup need three messages rather than two?
7. The advertised window
How does TCP keep a fast sender from over-running a slow receiver?
8. The silly window
A receiving application drains its buffer one byte at a time, and the sender ships one-byte segments in response. What is this failure called, and how does Nagle's rule prevent its sender side?
9. Poisoned samples
Why must TCP refuse to measure a round-trip sample from a segment that was retransmitted?
10. Mean plus deviation
When round-trip samples vary wildly, what does the Jacobson-Karels timeout do differently from the original twice-the-mean rule?
11. The four-tuple
A TCP connection is uniquely named by the source and destination ports together with which two further fields?
12. The lifetime bound
TCP assumes no segment lives longer in the network than the maximum segment lifetime, conventionally set to how many seconds?
13. The self-clocking rule
Whose algorithm forbids sending a small segment whenever unacknowledged data is outstanding, pacing transmission by returning acknowledgments?
14. The fourfold margin
In the Jacobson-Karels timeout, the estimated round-trip mean is added to how many times the estimated deviation?