Cheatsheet: Difference between revisions
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- Starts the Congestion Avoidance phase
- This is called fast transmission and fast recovery
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* Both consider RTO and Duplicate ACKs as packet loss events.
* Behavior of Tahoe and Reno differ primarily in how they react to duplicate ACKs.
Tahoe:
If three duplicate ACKs are received Tahoe performs a fast retransmit
Sets the slow start threshold to half of the current congestion window
Reduces the congestion window to 1 MSS
Resets to slow start state
Reno:
If three duplicate ACKs are received, Reno will perform a fast retransmit
Skip the slow start phase by instead halving the congestion window (instead of setting it to 1 MSS like Tahoe),
Setting the slow start threshold equal to the new congestion window
Enter a phase called fast recovery.
* In both Tahoe and Reno, if an ACK times out (RTO timeout), slow start is used, and both algorithms reduce congestion window to 1 MSS.
* Four ACKs acknowledging the same packet, which are not piggybacked on data and do not change the receiver's advertised window.
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*Silly Window Syndrome: Sender creates data slowly or Receiver consumes slowly or both.
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