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Careful Resume
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What's an unvalidated packet precisely? #35

Closed joergdeutschmann-i7 closed 2 months ago

joergdeutschmann-i7 commented 2 months ago

Section 3.3 Unvalidated Phase (Receiving acknowledgements for reconnaisance packets): The variable PipeSize is increased by the amount of data that is acknowledged by each acknowledgment (in bytes). This indicated a previously unvalidated packet has been succesfuly sent over the path.

Is an unvalidated packet simply a packet which has not been acknowledged yet? (I believe this is meant here because of the Receiving acknowledgements for reconnaisance packets.) If yes, maybe better write previously unacknowledged packet has been successfully sent? Anyway, whole sentence then seems superficial.

Or is an unvalidated packet a packet which is sent in the Unvalidated phase? If yes, this does not match the Receiving acknowledgements for reconnaisance packets. Also this would not be possible because we are just sending unvalidated packets in this phase and an ACK to those should trigger a transition to Validating.

s/succesfuly/succesfully

gorryfair commented 2 months ago

I think an "unvalidated packet" is one sent when the sender has exceeded the normal cwnd, and is Unvalidated. Once this packet is ACK'ed it contributes to the pipesize, since the receipt of the ACK has confirmed the packet travelled across the path (Validating). The only exception to this, is when congestion was detected, in which case the cwnd was not valid, and adjustments to cwnd need to reflect this (Safe Retreat).

The text ought to relate to packets sent in reconaissance, where the corresponding ACK is received in "Unvalidated", because of a change of state after the packet was sent.

So, I agree: "This indicated a previously unvalidated packet has been succesfuly sent over the path." ought to say "/unvalidated packet/previously unacknowledged packet/".