[e2e] Skype and congestion collapse.

[Emmanuel Papirakis]

Hello,

a VoIP application called Skype is gaining more and more popularity. I
did a basic capture using Ethereal. It seems that it continuously
sends data at a rate of 10 KB/sec.

Obviously, it does not use a sliding window mechanism nor does it
consider the rate at  which the receiver is able to receive data.
Furthermore, it does not attempt to detect periods of silence and
during those, it continues to send data at its 10KB/sec constant bit
rate.

A colleague of mine is very enthousiastic about Skype as it saves him
a lot of money on  his long distance bills. According to his vision of
Skype, one day, everybody is going to use Skype....

This scares me. Intuitively, this looks like the perfect recipe for a
congestion collapse. But, he argues that this could not be the case as
there are miles and miles of unused copper and fiber opticts out there
and that more bandwidth is widely available across the world...

IMHO, I think that applications like Skype should be responsible for
managing the congestion they could potentially cause. This brings me
to my question. If more and more applications start to behave like
Skype and selfishly worry more about their business model than about
the health of the global Internet, is there still a possibility of a
congestion collapse today ? Or, are those worries well behind because
the problem can be compensated by introducing more bandwidth into the
network ?

Thank you

Emmanuel

-- 
UNIX IS very user friendly. It is just selective about its friends...