[e2e] Explicit Transport Error Notification

[James Sterbenz]

At 02:12 PM 4/2/2002 -0800, Christian Huitema wrote:
 >> Will Ivancic wrote:
> > This work represents a very good start to investigations into ETEN.  I
> > would appreciate any feedback related to the work.  In particular,
> > thoughts on whether or not the potential performance improvements would
> > justify deployment.  If deployment is justified, which areas of research
> > may be best to address?
>
>Explicit error notification is just one way to distinguish between losses 
>due to transmission errors and losses due to congestion. An alternative 
>way is to use explicit congestion notification, and assume that packet 
>losses are due to other factors -- e.g., only shrink the window on ECN, 
>and expend it on the ACK. There are obvious deployment issues, but these 
>could be solved if NASA is operating in any kind of controlled set-up. In 
>any case, the ECN only option could be simulated in NS...

This is discussed in the report, but it is not quite so simple.  That is, a 
given packet can
cause congestion, and then also suffer a channel error.  So it is not true 
that you can
directly compute corruption from ECN or congestion from ETEN in the case of 
lossy congested
networks.

Cheers,
James

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James P.G. Sterbenz                                      jpgs at bbn.com
Senior Network Scientist                                 jpgs at acm.org
Research Group Manager                                +1 617 873 5063
Internetwork Research, BBN Technologies