[Gllug] What's that network congestion setting called?

[Ian Northeast]

Mark Hill wrote:
> On Mon, Feb 07, 2005 at 09:01:31AM -0000, John Winters wrote:
> 
>>I'm investigating a Linux box (running 2.6.8) which is getting very bad
>>network performance some of the time.  I recall a network negotiation
>>field which some routers don't implement correctly and can IIRC cause
>>symptoms similar to what I'm seeing, but after sleeping on it overnight I
>>still can't remember what it's called.
> 
> 
> ECN?

The ECN problem (which should be very rare by now) is caused by 
misbehaving routers dropping packets with ECN set when they're supposed 
to ignore it if they don't understand it. So, as when ECN is turned on 
all packets have the bit set, the effect is no communication at all 
across the bad router, not poor performance.

I suppose it's possible for dynamic route reconfiguration to cause some 
packets to go down a "good" route occasionally but I don't think it 
generally happens quickly enough.

Regards, Ian


-- 
Gllug mailing list  -  Gllug at gllug.org.uk
http://lists.gllug.org.uk/mailman/listinfo/gllug