[comp.mail.uucp] missing acks

dg@lakart.UUCP (David Goodenough) (05/04/89)

In a "g" protocol environment, I can see that the following could occur:

His receive window is size 3

I send packet 1, then 2, then 3.

He acks packet 1, but I miss the ack due to line noise.

He acks packet 2, and that ack gets through. I'm expecting an ack for 1,
but here's one for 2.
Can I assume that he saw packet 1 OK, because he's just acked packet 2? i.e.
does an ack for packet n count as an ack for all outstanding packets up to n.
-- 
	dg@lakart.UUCP - David Goodenough		+---+
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budd@bu-cs.BU.EDU (Philip Budne) (05/06/89)

In article <531@lakart.UUCP> dg@lakart.UUCP (David Goodenough) writes:
>Can I assume that he saw packet 1 OK, because he's just acked packet 2? i.e.
>does an ack for packet n count as an ack for all outstanding packets up to n.

Yes.  RR 2 ACKs all packets upto and including packet 2. RJ 3 does the
same AND requests retransmission of packet 3.

	Phil Budne
	Boston U

dtynan@altos86.UUCP (Dermot Tynan) (05/09/89)

In article <531@lakart.UUCP>, dg@lakart.UUCP (David Goodenough) writes:
>
> Can I assume that he saw packet 1 OK, because he's just acked packet 2? i.e.
> does an ack for packet n count as an ack for all outstanding packets up to n.
>
> 	dg@lakart.UUCP - David Goodenough		+---+

Yes.
The 'ACK' is for all packets up to and including 'N'.

						- Der
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