Transcript IRTF Peer-to-Peer Research Group Paris 2005 Meeting Co-Chairs: Bill Yeager and Bobby Bhattacharhee.

IRTF Peer-to-Peer Research
Group
Paris 2005 Meeting
Co-Chairs: Bill Yeager and Bobby Bhattacharhee
Agenda
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A short history
Overview of research group’s charter
What we’ve done so far
Mailing list organization
New proposals
What research might be standardized in the IETF?
A Short History
• Spring of 2002
– JXTA Protocols were submitted as a draft-rfc to bootstrap
the process leading to an IETF P2P Working Group
• Summer of 2002 at Yokohama IETF 54
– JXTA IPR (Some 40 Sun patents) were disclosed to the
IETF as per rfc2026,2028 (updated by rfc3979).
– Bill Yeager and Jeff Altman hosted a BAR BOF of the
IETF area directors and other interested parties to discuss a
P2P WG with the JXTA protocols as a starting point
• This was summarily rejected
– It was felt that more study was needed before starting a WG to
understand what is Peer-to-Peer, and given a reasonable definition,
then just what are the interfaces with the current IETF standards, etc.
A Short History
• Fall of 2002 at Atlanta IETF 55
• After a month’s worth of email exchanges with area directors and
IAB members, Jeff Altman and Bill Yeager were required to create
a less than ten line description of P2P and its IETF goals. We
managed to our own surprise and delight of the area directors and
IAB. The 10 lines:
The proposed IETF P2P working group will define the architecture and suite of
protocols necessary to implement an Internet, P2P overlay network (IP2PONET) to reenable application layer, global end-to-end communication. Such an IP2PONET is a
collection of Internet nodes that can communicate with one another and can run appservices wherein they play client/server roles. Nodes may be ad-hoc and autonomous,
or use traditional, centralized,client/server technologies. The IP2PONET may or may
not allow the definition of arbitrary namespaces. The WG is expected to use pre-existing
RFCs relating to IPv4/v6, URIs, http, and current work on TLS, S/MIME, PKI,
SACRED, XMLDSIG, DNSEXT, and MSEC. Depending on the WG directions, DHCP,
BEEP and XMPP might be utilized.
A Short History Continued
In Atlanta it was then decided that an IRTF p2p RG is
appropriate for this area and to this end the ball was
passed to Vern Paxson who was the IRTF chair at that
time.
• Early winter 2002
• As a first step, Vern, Bill and Jeff wrote the research group’s
charter. This took about 3 months to finish.
– Neutrality is important and is difficult to achieve.
• Late winter 2003
• Finally, the IRTF P2P RG was launched in early 2003 with Bill
Yeager and Bobby Battacharjee as the co-chairs.
P2P research group’s charter
A charter is a starting point, a way to set the direction and focus of our
research; it is not a mandate, and is mutable.
1. Begin with a simple definition of P2P
Peer-to-Peer (P2P) is a way of structuring distributed applications such that the individual nodes have symmetric
roles. Rather than being divided into clients and servers each with quite distinct roles (such as Web clients
vs. Web servers), in P2P applications a node may act as both a client and a server. P2P systems are in
general deployable in an ad-hoc fashion, without requiring centralized management or control. They can be
highly autonomous, and can lend themselves to anonymity.
2. Give IETF relevant historical examples (P2P is an old concept)
Some historical examples of P2P systems are USENET servers, built on top of NNTP, and inter-domain routing,
built on top of BGP.
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Note: Beginning in the late 70’s with the ARPANET and continuing in the 80’s with the Internet all
connectivity was end-to-end, and almost all hosted systems were peers of one another. The localand wide-area-networks as well as the Internet were used for massive exchange of data. Mounting
one another’s file systems with either NFS or AFS to copy data was generic P2P; MTA’s are also
peers, etc.
3. Point out the return to end-to-end connectivity
A key concept for P2P systems is to permit any two peers to communicate with one another in such a way that
either ought to be able to initiate the contact.
P2P research group’s charter
4. P2P can enable social interaction on the Internet
As such, P2P is a powerful tool for organizing cooperative communities - both in the research and
domains - with common goals.
commercial
5. Issues of research versus commercial interests
However, in practice, we find that the research and commercial worlds are driven by different needs. The former
often focus on developing generalized building blocks that can then be composed to realize P2P systems with
quantifiable properties. These building blocks sometimes arise out of analysis of the deficiencies of existing P2P
systems, attempting to overcome discovered shortcomings in areas such as peer-node organization, content
caching and distribution, lookup, search, discovery, routing, security and trust. The commercial P2P world, on the
other hand, is driven by the concerns of time-to-market and viable business models. Many commercial systems
have little concern for the research issues mentioned above, while the short-term concerns of commercial entities
are often not within the purview of academic research. Such discontinuities in perspective have led to a rift
between the two communities, bridging which will be of significant short- and long-term benefit.
6. Try to motivate these communities towards alignment, agreement
The P2P Research Group attempts to serve as such a bridge. First, the group offers a forum for researchers to
explore a broad range of fundamental P2P issues such as: peer-node identity, naming, configuration and
capabilities; P2P network organization and scope; resource discovery, content lookup, search and distribution;
request routing and operation in the presence of mobility; adaptation to expected peer-node instability; monitoring
of P2P operations; security of P2P systems involving reputation-based trust for ad-hoc systems or more
centralized, CA-like approaches; etc.
P2P research group’s charter
4. Historically commercial deployment has always raced ahead of research,
thus pointing out areas where research and standards are required
In addition, as commercial P2P deployment on the Internet has raced ahead of research and standards, issues as
basic as interoperable, scalable, P2P communication protocols have been set aside. There is no foundation upon
which one can build a unified, P2P network on the Internet: today's P2P protocols create disjoint islands of
isolated Internet nodes.
5. Our near-term goals
To this end, the research group also emphasizes the following near-term goals: classifying the P2P problem space
(both currently, and as it evolves) into those problems for which there are existing solutions and those for which
solutions require longer-term development; developing descriptive model(s) of peer-node organization whose
interpretation can be applied to these solutions; articulating the scope as to what sort of P2P applications the
models encompass and what sort they do not; understanding the unique security-related problems and
opportunities P2P systems pose; exploring interfaces to IETF protocols to realize the models; and offering input to
the IETF as a starting place for possible groups standardizing new protocols that are useful in building P2P
applications.
What we’ve done so far
• A growing bibliography of P2P references by Bobby with RG input:
http://www.cs.umd.edu/projects/p2prg/bib/
• A problem statement draft from the P2P RG mobility subgroup by Frank-Uwe
Andersen, Luca Caviglione and Oliver Waldhorst
(Currently email archive) It will be online in the next few weeks.
A summary is found at:
http://www-info3.informatik.uni-wuerzburg.de/staff/mopi/p2prgIRTFwashington2004.pdf
• A “Survey of Research Towards Robust P2P Networks” by John Risson and
Tim Moors of the University of South Wales:
http://www.cs.umd.edu/projects/p2prg/bib/
• Mailing list activities
– Lists maintained at both the IRTF and University of Maryland. More on
this later.
Mailing List Organization
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The primary list has a link at
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http://www.irtf.org/charters/p2prg.html
We’ve six research subgroups each with a
mailing list at
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1.
2.
3.
4.
5.
6.
http://mailman.cs.umd.edu/mailman/listinfo/p2prg-*
Applications: *=apps
Discovery, and Resource Location Protocols: *=drlp
Metadata: *=metadata
Mobility: *=mobility
Overlay: *=overlay
Security: *=security
Mailing List Reorganization
• Our consensus is that the mailing list
organization is too complicated
– The proposed solution is to have a single p2prg
mailing list at the University of Maryland and
use
Subject: [subgroup] text
to track research threads.
– Unless there are overwhelming objections, this
will be adopted after this conference.
Accepted New Research
Proposals
• Peer-to-Peer over IPV6 (Overlay subgroup)
– Proposed by Luca Caviglione
• [email protected]
• Peer-to-Peer Content, Resource and Service
Discovery (Discovery and resource location
protocol subgroup)
– Proposed by John Buford
• [email protected]
• Both proposals will have a link on the IRTF P2P
RG web-site in the next week or two.
• All interested parties are both encouraged and
welcome to participate in the research.
What Might Be Standardized?
•It is important to read RFC2014 on this
matter. A relevant excerpt:
The IRTF does not set standards, and thus has somewhat different and
complementary philosophy and procedures. In particular, an IRTF
Research Group is expected to be long-lived, producing a sequence of
"products" over time. The products of a Research Group are research
results that may be disseminated by publication in scholarly journals
and conferences, as white papers for the community, as Informational
RFCs, and so on.
In addition, it is expected that technologies developed in a Research Group will be brought to the IETF
as input to IETF Working Group(s) for possible standardization. However Research Group input
carries no more weight than other community input, and goes through the same standards setting
process as any other proposal.
Questions? Comments, Discussion