[p2p-sip] Revised Draft Charter for P2PSIP

Henry Sinnreich hsinnrei at adobe.com
Fri Sep 22 10:13:16 EDT 2006

This may not fit into the charter discussion, but joining Michael
Slavitch, I would be interested if any or what modifications ICE would
be required for P2P systems, where most peers reside behind a NAT.


Any opinions? Jonathan?


Thanks, Henry



From: p2p-sip-bounces at cs.columbia.edu
[mailto:p2p-sip-bounces at cs.columbia.edu] On Behalf Of Michael Slavitch
Sent: Friday, September 22, 2006 9:45 AM
To: Roy, Radhika R.
Cc: p2p-sip at cs.columbia.edu; David A. Bryan
Subject: Re: [p2p-sip] Revised Draft Charter for P2PSIP


It is certainly not a nonsense problem outside of some rare circles as
nearly all consumer and business networks fall behind NATs. Without NAT
crossing P2PSIP is useless. I agree that in a deterministic system a
perfect solution is required. 


That is why deterministic systems are always so brittle. The world is a
messy fractal place.


By definition P2PSIP will not be deterministic so a perfect solution is
not only unnecessary, it is not desirable if the cost of complexity
exceeds the apparent benefit.


The solutions that exist are statistical and fractal, not perfect and
deterministic. Skype is living proof of a broadly used implementation
that shows that the problem is solved in a matter that meets the
requirements for P2P systems.  Since all P2P systems share a common
fractal nature a fractal solution is perfectly suited to the domain.  


For all the criticism of ICE, and I've done my fair share, it is getting
simple enough to implement from the draft to be expressed in BNF
notation. It is now fairly easy to build ICE into a finite state
machine, as ICE now describes a completion mechanism where the protocol
is complete. That encourages  interoperability from the start.  


Any inadequacies that remain result from the fact that client-server SIP
is the only official user of the protocol.  These are minor issues that
can only be addressed by MMUSIC once we have a P2PSIP WG that can
request changes.  That is a diplomatic problem, not an engineering
problem, if the underlying protocol in ICE can meet base P2PSIP
requirements.  That is why WG chairs are chosen carefully. 


Regarding unsolved problems:  If the underlying system is fractal then a
statistical solution with a high probability of success meets the
requirements for the system. This is true for all fractal systems.   The
only issue is determining the probability of success of different
solutions and either choosing one that meets the circumstances at hand
or modifying another to make it an appropriate choice.  


I further argue that the fractal nature of ICE is far more suited to the
fractal P2P world than it is to the assumed-deterministic IMS/CS model.
It may be not ever be solved perfectly enough for IMS but for
self-organizing P2PSIP it won't have to be perfect as the nature of a
self-organizing systems is to work around their own shortcomings.
P2PSIP will be rugged enough such that perfect solutions are not needed.
If the other working groups are failing it may be because the systems
they are building towards may be broken and brittle and not rugged
enough to tolerate statistical solutions. Given the talent at hand that
will certainly not be the case with P2PSIP. 






On 9/21/06, Roy, Radhika R. <RADHIKA.R.ROY at saic.com> wrote: 


The ONLY reason is this: It is an unsolvable problem.

All IETF WGs have been trying, and have been failing successully!!! 

The word UNFORTUNATE is there to discourage for spending too much time
this technically nonsense problem. That is, p2p-SIP may not be even
WG anymore at the end of the solution - all fear is this: It might make 
p2p-SIP NAT crossing solution as non-p2p-SIP NAT crossing protocol.

I hope I would be  be wrong! Who knows what is coming out of by SIP,
SIPPING, NSIS, IPSEC, DIAMETER, and others almost after 6-10 years!
MMUSIC has turned their attention to ICE-xxxxxx versions.

Let us wait for ICE (versions # infinite) to see whether it could be
for p2p-SP!!! How about this?



From: Michael Slavitch [mailto: slavitch at gmail.com]
Sent: Thu 9/21/2006 2:32 PM
To: Roy, Radhika R.
Cc: David A. Bryan; p2p-sip at cs.columbia.edu
Subject: Re: [p2p-sip] Revised Draft Charter for P2PSIP 

The "NAT is evil" argument is a matter of faith and belief, a moral
statement that has no place in a protocol working group charter.
Engineering solutions emerge from the judicious study of discernible 
reality. NAT exists, therefore it must be dealt with. Period.
>From an engineering standpoint, it creates problems that need to be
with solutions that reflect the facts on the ground.

The P2PSIP Working Group must be part of the reality-based community,
than part of an ideological community, therefore the working group
must distinguish consensus external reality from ideologically created
reality if the working group is to be at all successful.  There is ample

evidence that creating one's own reality despite evidence to the
results in failure.

Given that, the word "unfortunate" has no place in an engineering
By definition it must be struck. 



On 9/21/06, Roy, Radhika R. RADHIKA.R.ROY at saic.com
<mailto:RADHIKA.R.ROY at saic.com>  wrote: 

Mike and all:

I am commenting on NATs.

>From IETF point of view, the use of NATs as it is done these days is

Let us see what had been the history of NAT standardization in the IETF?

The IETF charter had been to help the "scarcity" of IPv4 addresses
IPv6 even been proposed). It was hoped that, by the time IPv6 is
standardized, there is will be no more requirements of NATs to provide
address spaces.

Now, people have forgot the original usage of NATs. People are using
NATs as
a part of "security" for hiding the configurations behind NATs. It is
completely an "illusion" to be happy to know that people are "secured"
using NATs. It is still going on in a mass scale throughout the world,
no one knows when this will be stopped.

Should the purpose of the NAT standardization be "SECURITY" or "TOPOLOGY
HIDING in the name of security," IETF would NEVER standardized NATs for 
these purposes. The rest is history!!!

So, it is UNFORTUNATE so far the MIS-use of NATs is concerned because
are not needed anymore due to shortage of IPv4 addresses or NATs cannot
provide security through hiding configurations. 

Therefore, the draft charter is CORRECT in this context to use the word

Best regards,


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