Re: hotmail not dealing with ECN

[Jamie Lokier]

Gregory Maxwell wrote:
> > Why? Why not just zero them, and get both security and compatibility...
> 
> Eeek! NO!!!! NO NO NO NO NO NO NO!
> For ECN that would have worked, but that doesn't mean that something
> couldn't have been implimented there that wouldn't have worked that way..
> 
> I think that older Checkpoint firewalls (perhaps current?) zeroed out SACK
> on 'hide nat'ed connections. This causes unreasonable stalls for users on
> SACK enabled clients. Not cool.

If both SACK and SACK_PERMITTED were zeroed out, the clients would
negotiate non-SACK connections and everythings ok.  A performance
disadvantage relative to allowing SACK, but that's true of ECN as well.

-- Jamie