Peer-to-Peer and Peer-to-Peer and Collective IntelligenceCollective Intelligence

A platform for collaborationA platform for collaboration

Andrew Roczniak

Collective Intelligence LabMultimedia Communications Research Lab

University of Ottawa

August 9th, 2004

AgendaAgenda

Examples of How P2P WorksExamples of How P2P Works

DefinitionsDefinitions

ApplicationsApplications

P2P Architecture BenefitsP2P Architecture Benefits

Requesting ContentRequesting Content

Server

Internet

Client

Client

Client

WWW, HTTP

Content Distribution NetworksContent Distribution Networks

Server

Internet

Server

Server

Server

Server

Client

Client

Client

Akamai, Digital Island

Content Distribution on P2PContent Distribution on P2P

Server

Internet

Peer

Peer

Peer

Peer

Peer

Peer

P2P Network

Streaming ContentStreaming Content

Server

Internet

Peer

Peer

Peer

Peer

Peer

Peer

P2P Network

Streaming Content InfrastructureStreaming Content Infrastructure

Server

Internet

Peer

Peer

Peer

Peer

Client

Client

Client

Client

Client

Client

P2P Network

I want content!

We want content too!

Distributed StorageDistributed Storage

Client

Client

Client

Client

Client

Client

Data Storage

Data Storage

Data Storage

P2P Network

I need storage space!

I have some

I have some

Summary - Which Applications?Summary - Which Applications?

Content deliveryContent delivery File sharingFile sharing Streaming (Video conference, Audio)Streaming (Video conference, Audio)

End-HostEnd-Host

InfrastructureInfrastructure

Network StorageNetwork Storage

DefinitionsDefinitions

““Peer to peer is essentially a Peer to peer is essentially a technological technological communications method wherecommunications method where all parties all parties are equalare equal. The Web is not peer-to-peer, it . The Web is not peer-to-peer, it has a server-to-client model. On the Web has a server-to-client model. On the Web P2P refers specifically to a network P2P refers specifically to a network established by a group of users sharing established by a group of users sharing the same software program, like Napsterthe same software program, like Napster.”.”

Source: Condensed Net Glossary http://www.saila.com/usage/glossary/Source: Condensed Net Glossary http://www.saila.com/usage/glossary/

DefinitionsDefinitions

““From user to user. From user to user. Peer-to-peer implies that either side Peer-to-peer implies that either side can initiate a session and has equal responsibility.can initiate a session and has equal responsibility. Peer- Peer-to-peer is a somewhat confusing term, because it has to-peer is a somewhat confusing term, because it has always been contrasted to a central system that initiates always been contrasted to a central system that initiates and controls everything. But in practice, two users on a and controls everything. But in practice, two users on a peer-to-peer system often require data from a third peer-to-peer system often require data from a third computer. For example, the infamous Napster file computer. For example, the infamous Napster file sharing service was always called a "peer-to-peer sharing service was always called a "peer-to-peer network," but its use of a central server to store the network," but its use of a central server to store the public directory made it both centralized and peer-to-public directory made it both centralized and peer-to-peer“peer“

Source: http://www.techweb.com/encyclopediaSource: http://www.techweb.com/encyclopedia

DefinitionsDefinitions

““P2P computing is the P2P computing is the sharing of computer sharing of computer resources and servicesresources and services by direct exchange by direct exchange between systemsbetween systems. These resources and . These resources and services include exchange of information, services include exchange of information, processing cycles, cache storage, and processing cycles, cache storage, and disk storage for files.”disk storage for files.”

Source: P2P Working GroupSource: P2P Working Group

DefinitionsDefinitions

““A distributed network architecture may be called a Peer-to-A distributed network architecture may be called a Peer-to-Peer network, if the participants sharePeer network, if the participants share a part of their own a part of their own hardware resources (processing power, storage hardware resources (processing power, storage capacity, network link capacity, printers). capacity, network link capacity, printers). These shared These shared resources are necessary to provide the service and resources are necessary to provide the service and content offered by the networkcontent offered by the network (e.g. file sharing or (e.g. file sharing or shared workspaces for collaboration). shared workspaces for collaboration). They are They are accessible by other peers directly, without passing accessible by other peers directly, without passing intermediary entitiesintermediary entities. The participants of such a network . The participants of such a network are thus resource (Service and content) providers as are thus resource (Service and content) providers as well as resource (Service and content) requestors well as resource (Service and content) requestors (Servent).”(Servent).”

Source: R. Schollmeier, “A Definition of Peer-to-Peer Networking for the Classification Source: R. Schollmeier, “A Definition of Peer-to-Peer Networking for the Classification of P2P Architectures and Applications”, IEEE P2P Conference, 2001of P2P Architectures and Applications”, IEEE P2P Conference, 2001

DefinitionsDefinitions

““P2P is a class of applications that takes P2P is a class of applications that takes advantage of resources e.g. storage, advantage of resources e.g. storage, cycles, content, human presence, cycles, content, human presence, available at the edges of the Internetavailable at the edges of the Internet””

Source: OpenP2P.com, Clay ShirkySource: OpenP2P.com, Clay Shirky

What P2P isWhat P2P is

A Mind SetA Mind Set A system and/or application that takes advantage of resources at the A system and/or application that takes advantage of resources at the

edge of Internet or supports direct interaction among users. edge of Internet or supports direct interaction among users. A ModelA Model

A system and/or application that does not rely on fully centralized or A system and/or application that does not rely on fully centralized or client/server approachclient/server approach

An Implementation ChoiceAn Implementation Choice Example: application layer multicastExample: application layer multicast

A property of a System or an EnvironmentA property of a System or an Environment Certain situations require a P2P solution (lack of infrastructure, Certain situations require a P2P solution (lack of infrastructure,

scalability, reliability)scalability, reliability)

From: “Peer-to-Peer Computing”, Dejan S. Milojicic et al. From: “Peer-to-Peer Computing”, Dejan S. Milojicic et al.

ApplicationsApplications

Instant MessagingInstant Messaging ICQ, MSN Messenger, Lotus SametimeICQ, MSN Messenger, Lotus Sametime

BroadcastingBroadcasting

Distributed Search EnginesDistributed Search Engines

Group CollaborationGroup Collaboration Groove NetworksGroove Networks

Distributed ComputingDistributed Computing

TelephonyTelephony SkypeSkype

P2P Architecture BenefitsP2P Architecture Benefits

Cost sharing and cost reductionCost sharing and cost reduction. . A P2P architecture can help spread costs A P2P architecture can help spread costs

over all participantsover all participants

Improved reliabilityImproved reliability No single point of failureNo single point of failure

Scalability and resource aggregationScalability and resource aggregation Peers bring resources such as bandwidth, Peers bring resources such as bandwidth,

computing power or storage spacecomputing power or storage space

P2P Architecture CharacteristicsP2P Architecture Characteristics

AutonomyAutonomy Users may be unwilling to rely on any Users may be unwilling to rely on any

centralized service provider centralized service provider

DynamismDynamism Peers can enter and leave the system freelyPeers can enter and leave the system freely

Ad-Hoc collaborationAd-Hoc collaboration Application-level collaboration between users. Application-level collaboration between users.

Peers form a group of two or more users Peers form a group of two or more users based on their current interestsbased on their current interests

CriteriaCriteria

BudgetBudget

Resource Relevance to ParticipantsResource Relevance to Participants

TrustTrust

Rate of System ChangeRate of System Change

CriticalityCriticality

M. Roussopoulos, M. Baker, D. S. H. Rosenthal, T.J. Giuli, P. Maniatis, M. Roussopoulos, M. Baker, D. S. H. Rosenthal, T.J. Giuli, P. Maniatis, J. Mogul, “2 P2P or Not 2 P2P?”, IPTPS 2004J. Mogul, “2 P2P or Not 2 P2P?”, IPTPS 2004

Decision TreeDecision Tree

!

Rate of Change!

!

!

Budget

Relevance

TrustTrust

Rate of Change

Criticality Criticality

Corporate Storage

FreeNet

Content Distribution

Flash Crowds

MP3Sharing

Low High

Low High

Low

Low

High

High

Low

Low

Low Low

High

High

HighHigh

ConclusionConclusion

The goal of this section was to explain The goal of this section was to explain what P2P iswhat P2P is

P2P is more than just sharing copyright P2P is more than just sharing copyright materialsmaterials

Questions?Questions?