Voxilla's Interview with me on P2P VOIP

3 responses to “Voxilla's Interview with me on P2P VOIP”

1. 

   David Barrett says : August 6, 2005 at 1:01 am

   Here’s a message I sent Erik earlier (about a July 25th post), that he asked I post here. I’ve included it in its entirety, and will follow up with another post after.

   —–Original Message—–
   From: David Barrett [mailto:dbarrett@quinthar.com]
   Sent: Tuesday, August 02, 2005 3:11 AM
   To: erik@sipthat.com
   Subject: Re: P2P VoIP using SIP and Open Standards

   Hi, sorry for the late reply to your July 25th posting about P2P SIP, but
   you posed the question:

   >> Everyone is looking for a new solution for P2P VoIP, I think P2P SIP
   >> is the answer, do you?

   My answer is no, I don’t believe P2P SIP is the key to P2P VoIP. More
   specifically, I don’t think an IETF standard for decentralized SIP proxies
   will gain traction because it solves problems that nobody has, while
   complicating the problems that we do.

   Now, I recognize VoIP will grow, and the actual media components will
   migrate to P2P. But I do not believe the SIP proxy component of the global
   architecture gains anything by being decentralized in this way.

   My reasoning is based on the observation that P2P is primarily useful in two
   situations:

   a) When a centralized solution is too costly
   b) When a centralized solution is legally vulnerable

   Consider the case of Napster. A kid in a college dorm room was able to host
   a global rendezvous service (akin to a SIP proxy) for millions of
   simultaneous users, for free. Obviously, he didn’t suffer from (a).
   But (b) was what took him down, and thus gave rise to Gnutella (et al).

   But had (b) not occurred (ie, had the courts ruled in favor of Napster), I
   offer that Gnutella simply would not exist because it offers precisely zero
   incremental value. It is slower, less reliable, and less comprehensive than
   Napster could have been. Had Napster been allowed to grow, it could have
   offered better services, evolved faster, and been superior in every
   measurable way.

   SIP proxies are today like Napster was then. But VoIP isn’t illegal, and
   thus a SIP proxy is not a legal vulnerability. Thus I see no reason to
   believe that a decentralized alternative to a SIP proxy would warrant the
   resulting complexity cost inherent in any “pure”-P2P solution.

   All that said, I do believe that P2P is the future of VoIP, and near-free
   services will be the business model. I merely think that the SIP proxy part
   of the equation is best left centralized.

   -david
2. 

   David Barrett says : August 6, 2005 at 1:11 am

   So again, I’m still not sold on the benefits of P2P SIP. I think it’s cool, don’t get me wrong. And the idea of setting up an instant P2P network in the middle of a desert or in a disaster area is appealing, certainly. But you have to admit those are rather extreme circumstances. For the remaining 99.999% of actual real world users, this is not the case.

   Furthermore, I agree that the servers at Free World Dialup and other free SIP services cost money. But not much, else they wouldn’t be free. For under $100/mo you can get a dedicated server right on the backbone. The cost of deploying and maintaining hardware is virtually negligible these days.

   The real costs come in managing the network, and this is where centralized services come in handy.

   So P2P SIP is cool, certainly. And it might be handy the extreme situations you offer. But by the time the intrinsic decentralized problems have been hammered out, a centralized alternative will already dominate the landscape. And when it comes to competition, the decentralized solution offers no significant real world advantage (cost, reliability, performance) to anyone (user, administrator), while offering significant drawbacks in terms of complexity and the overall uncontrolled nature of P2P.

   Would you disagree? I mean, except for disaster areas and deserts, and except for saving $100/mo for a million users, what’s the benefit?

   Furthermore, do you acknowledge the disadvantages in terms of reliability and performance (ie, global distributed search versus database lookup) of a P2P solution? How would you argue the benefits outweigh the detriments?

   -david
3. 

   Aswath Weblog says : August 13, 2005 at 11:37 am

   P2P, SIP and Security

   For the past couple of days, Erik has posted discussions on SIP based P2P and security issues. These discussions are in audio format and are really interviews with Cullen Jennings, Rohan Mahy and Erik’s interview to Voxilla. The following is…