P4P : Provider Portal for (P2P) Applications Laird Popkin Pando Networks, Inc Haiyong Xie Laboratory of Networked Systems Yale University

P2P : Bandwidth Usage Up to 50-70% of Internet traffic is contributed by P2P applications Cache logic research: Internet protocol breakdown 1993 – 2006; Velocix: File-types on major P2P networks. Traffic: Internet Protocol Breakdown File-Types: Major P2P Networks

A Fundamental Problem Network-oblivious P2P applications may not be network efficient  50%-90% of existing local pieces in active users are downloaded externally  Average P2P bit traverses 1000 miles / 5.5 metro hops in Verizon network Traditional Internet architectural feedback to applications is limited:  routing (hidden)  rate control through coarse-grained TCP congestion feedback Emerging applications such as P2P can have tremendous flexibility in shaping how data is communicated  more information and feedback are needed to most effectively utilize this flexibility, and for improving network efficiency

P4P Mission Design a framework to enable better providers and applications cooperation  ISP perspective: guide applications to achieve more efficient network usage  P2P perspective: better user experiences P4P: provider portal for (P2P) applications  a provider can be a traditional ISP (e.g., AT&T, Verizon) or a content distribution provider (e.g., Akamai), or a caching provider (e.g., PeerApp)

The P4P Framework: Control Plane iTracker: a portal for each network resource provider (iPortal) An iTracker provides multiple interfaces  Static topology / policy  Provider capability  Virtual cost …… iTracker of a provider can be identified in multiple ways e.g., through DNS SRV records; whois iTracker can be run by trusted third parties iTracker access protected by access control

Virtual Cost Interface: Network’ Internal View PIDs: set of nodes each called a PID E: set of links connecting PIDs p e : the “virtual price” of link e Usage of “virtual price”  vPrice can be used to rank peers, converted to peering weights  vPrice reflects both network status and policy, e.g., OSPF weights higher prices on links with highest util. or higher than a threshold congestion volume (Briscoe) PID1PID2 PID3PID6 PID5PID

Virtual Cost Interface: Applications’ View  ISP computes the cost from one PID to another - link cost and routing  PID-pair costs are perturbed to increase privacy PID1PID2 PID3PID6 PID5PID Applications query costs of related PID pairs, adjust traffic patterns to place less load on more “expensive” pairs

Interdomain: Application External View Application obtains cost for top (ASN, PID) pairs (AS1, PID1) (AS2, PID2) Intradomain cost + interdomain cost From AS 1’s point view Intradomain cost + interdomain cost From AS 2’s point view

ISP A Example: P4P Protocol for BT pTracker iTracker peer Information flow: 1. peer queries pTracker 2/3. pTracker asks iTracker for virtual cost (occasionally) 4. pTracker selects and returns a set of active peers, according to both the virtual prices and its own P2P objective

Complete Set: Feb 21 to April 2008 FTTH 209% faster

Current P4P-WG: 70+ Members Core Group AT&T Bezeq Intl BitTorrent Cisco Systems Comcast Grid Networks Joost LimeWire Manatt Oversi Pando Networks PeerApp Solid State Telefonica Group Velocix VeriSign Telecom Italia Verizon Vuze University of Toronto Univ of Washington Yale University Observers Abacast AHT Intl AjauntySlant Akamai Alcatel Lucent CableLabs Cablevision Cox Comm Exa Networks Juniper Networks Lariat Network Level 3 Communications Limelight Networks Microsoft MPAA NBC Universal Nokia Orange Princeton University RawFlow RSUC/GweepNet SaskTel Solana Networks Speakeasy Network Stanford University Thomson Time Warner Cable Turner Broadcasting UCLA ISPs, P2Ps, Researchers. Scope includes business processes, protocols, education, etc.

Discussions I: Possible modifications to/uses of IETF protocols  Trackerless p2p use a mechanism to locate iTrackers (e.g. DNS)  Tracker-based p2p A mechanism for clients to find their (ASN, PID) (i.e. easier than IP mapping) A lookup mechanism for finding the iTracker for a given ASN. Enable P2P to "play nice" with ISPs  A mechanism for determining the ISPs usage policies, and the user's usage against quota. Imagine using a cell phone without being able to tell how many minutes you've used.  A standard mechanism for marking "bulk data" (i.e. not time sensitive).

Discussions II: P4P Data Plane Routers mark packets to provide faster, fine-grained feedbacks, e.g., virtual capacity to optimize multihoming cost and performance - applications adjust traffic rates according to feedbacks ISP BISP A a b Applications mark importance of traffic