Henry Sinnreich's Notes from IETF 63 Informal P2P SIP BOF
The BOF on P2P SIP at the 64 IETF in Paris was organized and chaired by Henning Schulzrinne and I am using the notes displayed by the chair during the meeting to provide some text around them. The original notes are at http://www.softarmor.com/sipping/meets/ietf63/slides/p2p-henning-sipping-ietf63.ppt
The meeting was very well attended and Cullen Jennings estimates the number of attendees was around 125.
(Henry's Note: Among the reasons for such impressive attendance may have contributed several facts, such as: P2P traffic dominates the Internet and the largest VoIP provider is Skype using P2P, though not SIP; see also http://linuxreviews.org/news/2004/11/05_p2p/ and http://www.cachelogic.com/p2p/p2ptraffic.php ).
Ongoing Efforts on P2P SIP
SIP DHT David Brian and Cullen Jennings reported on their work to use SIP for the Distributed Hash Tables (DHT). This work is also available online at http://www.p2psip.org/draft-bryan-sipping-p2p-01.html
P2P SIP IP PBX
Philip Matthews from NIMCAT Networks (http://nimcatnetworks.com/ ) shared the approach using multicast bindings and several layers to achieve P2P functionality. Henry's note: There are several P2P enterprise systems on the market, such as http://peerio.com/, http://www.aastra.com/enterpriseip/pro_228.asp and probably other as well.
Home Networks
Eunsoo Shim from Panasonic reported on research targeted on discovery and communications between consumer home network devices that support video and other types of multimedia.
IMS-like functionality
Marc Bailey from France Telecom shared information on research on P2P SIP targeted on IMS-like carrier services in a distributed environment. Similar work seems to be ongoing at Vodaphone.
Taxonomy for P2P SIP
There was a discussion on the need to publish a taxonomy for terms used in P2P SIP.
Where Next?
Several speakers mentioned related efforts, such as in IETF RG on P2P, See http://www.irtf.org/charter.php?gtype=rg&group=p2prg, but the comments made were that P2P SIP cannot wait for the research work in P2PRG and real time communications may have different requirements.
Applications of P2P SIP
An astonishing wide range of applications was mentioned for P2P SIP, such as:
- Rendezvous and signaling,
- Configuration files for devices, watcher lists, address books
- Media storage such as voice mail,
- Identity assertion
- Anonymity for both signaling and media,
- Distributed gateways (an original idea for Free World Dialup)
- Discovery of the best media relay for NAT traversal in overlay networks,
- Farms of SIP registrar/proxy servers that are the P2P supernodes for a service provider. The deployment of self organizing networks.
- Service discovery, such as finding where to download ring tones.
Problems and Challenges for P2P SIP
The technical challenges for P2P SIP seem to match the opportunities
- How to scale P2P further than the local network,
- Reliability and how to diagnose problems,
- Federation and communications between P2P SIP networks,
- Interconnection of P2P and client server SIP networks,
- What are the trust models and who can see my data?
- Data storage, such as voice mail: In random phones or only in phones of trusted buddies?
- Identity theft and providing unique identity. Is this a P2P SIP problem?
Documentation
David Bryan and several contributors are maintaining the web site with information on P2P SIP. See http://www.p2psip.org
I would also like to point to some of the impressive work at Columbia University:
- http://www1.cs.columbia.edu/~library/TR-repository/reports/reports-2004/cucs-044-04.pdf
- http://www1.cs.columbia.edu/~kns10/publication/sip-p2p-short.pdf
- http://www1.cs.columbia.edu/~kns10/talks/p2psip-panasonic.ppt
- http://www1.cs.columbia.edu/~kns10/publication/sipload.pdf
What's Next?
- Should there be a formal IETF WG on P2P SIP?
- The need for a mailing list. Henning Schulzrinne has in the meantime set up the list: See http://lists.cs.columbia.edu/mailman/listinfo/p2p-sip
- There will probably a workshop just before the next IETF in Vancouver ((November 6 - 11, 2005), see http://ietf.org/meetings/meetings.html and you may wish to bloc the calendar accordingly.
Thanks, Henry