Download P4P: Proactive Provider Assistance for P2P

P4P : Provider Portal for (P2P)
Applications
Haiyong Xie
Laird Popkin
Laboratory of Networked Systems
Yale University
Pando Networks, Inc
P2P : Bandwidth Usage
Traffic: Internet Protocol Breakdown 1993 - 2006

File-Types: Major P2P Networks - 2006
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.
A Fundamental Problem

Network-oblivious P2P applications may not be
network efficient

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Traditional Internet architectural feedback to applications is
limited:

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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
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



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Static topology / policy
Provider capability
Virtual cost
…
iTracker of a provider can be identified in multiple ways

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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



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PIDs: set of nodes each
30
called a PID
E: set of links
PID6
connecting PIDs
pe: the “virtual price”
15
of link e
Usage of “virtual price”


PID1
70
PID2
20
10
PID5
60
PID3
10
PID4
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)
Virtual Cost Interface: Applications’ View
 ISP computes the cost from
PID1
30
70
10
PID2
one PID to another
- link cost and routing
 PID-pair costs are perturbed
60 20
to increase privacy
PID6
PID3
PID5
PID4
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
Intradomain cost + interdomain cost
From AS 1’s point view
(AS1,
PID1)
(AS2,
PID2)
Intradomain cost + interdomain cost
From AS 2’s point view
Example: P4P Protocol for BT

pTracker
iTracker
2
3
1
4
ISP A
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
ISPs, P2Ps, Researchers. Scope includes
business processes, protocols, education, etc.
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
Discussions I:

Possible modifications to/uses of IETF protocols

Trackerless p2p

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Tracker-based p2p

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use a mechanism to locate iTrackers (e.g. DNS)
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
ISP A
ISP B
b
a
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
Applications mark importance of traffic