Selfish routing

alex at alex at
Sun Apr 27 22:22:49 UTC 2003

> > alex at wrote:
> > >>But curiously, adding some 
> > >>incremental capacity to a network can, under some conditions, actually 
> > >>make it worse!
> > >
> > >Oh, rubbish.
> To alex:  It's not necessary to add a tiny link to the network
> to make things worse.  In fact, the actual Braess Paradox example
> that roughgarden uses arises from the addition of a high-capacity,
> low-latency link in the wrong place.  It presumes the existence of
> a smaller capacity path through the network somewhere, but are you
> arguing that those paths don't exist?  I can show you a lot of them,
> since it's what my software (the aforementioned MIT RON project) is
> designed to exploit.  The Internet is full of weird, unexpected paths
> when you start routing in ways that the network designers didn't  intend.
> And that's what selfish routing _does_.

To those who really dont get what I am saying:

If you do not have enough capacity, the selfish or non-selfish routing does
                                not matter.

99.99999% of network problems are caused by CAPACITY issues be that packet
loss, or routers incapable of dealing with the traffic.

Addressing 0.00001% of problems caused by selfish routing is not going to
make it better. Address the issues that cause 99.99999% of the problems
before addressing 0.00001%


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