Re: mirage-www

[Richard Mortier <Richard.Mortier@xxxxxxxxxxxxxxxx>]

On 7 Sep 2012, at 16:04, Jon Crowcroft wrote:

> No, sequence numbers apply to bytes of payload data

ah- it's just the SYN that applies to -- from rfc 793, p31:

  In line 2 of figure 7, TCP A begins by sending a SYN segment
  indicating that it will use sequence numbers starting with sequence
  number 100.  In line 3, TCP B sends a SYN and acknowledges the SYN it
  received from TCP A.  Note that the acknowledgment field indicates TCP
  B is now expecting to hear sequence 101, acknowledging the SYN which
  occupied sequence 100.

in that case, no idea :)

looks like the client certainly thinks things should be ack-ed further into the 
stream. wireshark is having one of its (many) "moments" on my mac so i can't 
actually open the file again (opening wireshark currently causes it to fork 
bomb the mac with processes that activity monitor reports as "wireshark" and ps 
reports as "dumpcap"...).

> On 7 Sep 2012 15:21, "Richard Mortier" <Richard.Mortier@xxxxxxxxxxxxxxxx> 
> wrote:
> 
> On 7 Sep 2012, at 14:02, David Scott wrote:
> 
> > ...It looks like a problem in TCP. Anyone got any hints where to look?
> 
> not specifically, but it looks like the server is acking up to byte 112; the 
> 3 repeated acks up to 112 trigger the fast retx as they should.
> 
> isn't the server supposed to ack 1 past (because the ack itself counts as a 
> byte)?  ie., to 113.  (certainly that would explain why the client keeps 
> treating the ack to 112 as a request for retx.)
> 
> 
> --
> Cheers,
> 
> R.
> 
> 
> 
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-- 
Cheers,

R.