[ NNSquad ] Re: Fear mongering and trolls (Re: Keith Dawson: uTorrent Responds Regarding UDP Usage)

["George Ou" <george_ou@lanarchitect.net>]

I don't believe Richard or Brett ever claimed that using UDP is dangerous in
general.  What they said was that using UDP for things other than small and
short bursts of data (like DNS) which don't warrant the overhead of TCP or
other than low/fixed bandwidth applications like VoIP or online gaming is
bad.  Your point #2 illustrates the potential problems nicely and it isn't
all that different than the concern Richard raised.


George

-----Original Message-----
From: nnsquad-bounces+george_ou=lanarchitect.net@nnsquad.org
[mailto:nnsquad-bounces+george_ou=lanarchitect.net@nnsquad.org] On Behalf Of
David P. Reed
Sent: Tuesday, December 02, 2008 9:43 AM
To: nnsquad@nnsquad.org
Subject: [ NNSquad ] Fear mongering and trolls (Re: Keith Dawson: uTorrent
Responds Regarding UDP Usage)

There has been huge confusion appearing on this list regarding UDP.  The 
view that UDP = danger has been expressed.
This is incorrect, and seriously counter productive, especially if these 
arguments are presented to policy makers.

I will keep this brief, but am willing to expand on these points if 
necessary.

1) UDP is not "dangerous".  It is a well-understood standard, and 
requires only a little care in use to do things that *are not possible* 
using TCP.  As an example, the dominant VoIP standard, SIP, uses UDP (as 
the transport for RTP), so if we were to ban UDP, it would break VoIP as 
well!   Similarly, streaming video standards use UDP.

2) If there is an issue at all, it is that BitTorrent might not "back 
off" when congestion occurs in some downstream router.  That's not a 
good way to design BitTorrent, because it will make BitTorrent work 
*worse*, by forcing the routers that get congested to discard the 
BitTorrent packets themselves.

I have some confidence that BitTorrent and uTorrent guys actually know 
how to implement protocols that work - I know the inventor of 
BitTorrent, and he is quite savvy, and has shown a great deal of 
interest in making protocols that "behave".   If they do not work (and 
there is a technical measure of this, well known in the congestion 
control community) then they can be fixed.

3) The Internet has shown itself to be pretty robust, all things 
considered.  Many fear-mongers (starting with Bob Metcalfe) have claimed 
that it will all come crashing down.  It has not.  It hasn't even come 
close, though some people like to tell just-so stories about one or 
another large-scale problem.   The proper response to a problem is to 
measure it, understand it, and fix it.

Here's my advice: Don't listen to fear-mongers.  Ask for data that shows 
evidence for their claims.  Take a deep breath. Evaluate the risk, and 
take a measured response.  Don't buy gear from fear-mongering 
salespeople with kludges like "RST injection" or Deep Packet Inspection.

   [ For readers who are unfamiliar with David, he *created* UDP, so
     he knows of what he speaks.  David also makes another important
     point -- when there are problems, the proper course is to fix
     them.  Brett suggested that years ago I postulated an "Internet
     Meltdown."  What he's actually referring to is a PFIR
     conference I held aimed at finding specific solutions to
     *prevent* the meltdown of the Internet.  And so far we have
     collectively succeeded.  But many of the same risks do remain,
     if changed in form -- and new risks have since appeared,
     especially commercial and policy-related, rather than strictly
     technical.  There's continuing work to do -- that's part of
     what this list is about.

     It's similar in a way to the situation we had around Y2K.  If
     steps hadn't been taken proactively to fix what needed to be
     changed, there could have been some serious problems (though
     civilization wasn't going to collapse from Y2K failures in any
     case).  But we did what needed to be done, and actual Y2K
     problem events were comparatively limited in number and
     severity.

     In the case of Y2K though, we were mainly dealing with technical
     changes.  With the Internet, the intersection of technology and
     policy with commercial interests makes for a considerably 
     more complex situation.  But we can succeed, if we have
     (as Dr. Strangelove would say) the will to do so!

     -- Lauren Weinstein
        NNSquad Moderator ]