FairPeers: Efficient Profit Sharing in Fair Peer-to-Peer Market Places Giancarlo Ruffo, Schifanella Rossano Dipartimento di Informatica Università degli Studi di Torino

Key Question Is P2P mature enough for a fair, profitable, and dependable market place infrastructure? Giancarlo Ruffo, Schifanella Rossano, Università di Torino (Italy)

Motivations and Target DRM vs DRM-free debate is turning to a negotiation between big actors; What about the “long tail”? Centralized markets are efficient and dependable. But are they scalable and economically affordable for all? We, the long tail, claim that: P2P can significantly reduce costs, improve scalability, and distribute the profits. Giancarlo Ruffo, Schifanella Rossano, Università di Torino (Italy)

P2P Distribution Model Production 01010 10100 10101 Industry-side User-side Authoring 01010 1000 10101 Giancarlo Ruffo, Schifanella Rossano, Università di Torino (Italy)

P2P Roles and Interactions Providing Interaction Partner Receiving Interaction Partner Legal Owner of the Object Mediating Service Object of Interaction provides receives owns the rights of facilitates the interaction The Owner can be the provider or a third party A Peer can be both a Provider as well as a Receiver Digital Content Digital content sharing service (optional) Giancarlo Ruffo, Schifanella Rossano, Università di Torino (Italy)

A General Revenue Framework You can release an open platform, own the community, acquire licences, digitalize content and insert items in the network. But it is not finished yet: 1° issue: No clear economic value for owners 2° issue: No clear economic value for providers and/or mediator 3° issue: No trivial technical solutions Are these issues solvable in a realistic way? Giancarlo Ruffo, Schifanella Rossano, Università di Torino (Italy)

Features of a Fair P2P Market-Place Security Mechanisms against profitable frauds and attacks by malicious peers Efficiency and scalability High volume of transactions Huge population of users Protecting Copyright Legality of items traded Other forms of licenses can be considered as well (e.g., GPL, CC) Profit Sharing All the participants are part of the revenue model (i.e., peers contribute with disk space, cpu cycles or bandwidth) The cost of an object f has an authoring component Ca(f) and a distribution component Cd(f) Incentives to cooperate P2P distribution: Roles of owners (i.e., author), distributors (i.e., merchant), and receivers (i.e., buyer) are interchangeable G. Ruffo, R. Schifanella FairPeers: Efficient Profit Sharing in Fair Peer-to-Peer Market Places Journal of Network and Systems Management (JNMS), September 2007 (to appear). Giancarlo Ruffo, Schifanella Rossano, Università di Torino (Italy)

FairPeers: actors and roles A copy protected digital Object f The Owner of object f. This relationship is given by: a Copyright Certificate, that binds f and its owner The Distributor of object f, who has been delegated by the owner by means of: a Distribution License, that authorizes the distribution of the content The Receiver of f, that buys and downloads the object from the owner or via a (set of) licensed distributor(s) The receiver may become a distributor later on Some Mediators provide basic functionalities: Copyright Grantor (CG): stores the authorship’s information of all the items Certification Authority (CA): certifies for users’ identities (a PKI is assumed - each peer X holds a key pair <SKX,PKX>) A Broker: when a token-based accounting system with central bank is assumed Giancarlo Ruffo, Schifanella Rossano, Università di Torino (Italy)

FairPeers: Publishing of an Inedited Content Owner Copyright Grantor CERTIFICATION REQUEST f,{idf,idA,f,v,DL}SKA {idf,idA,f,LS,v,DL}SKCG COPYRIGHT CERTIFICATE idf,idA: content and owner identifiers f: medatata v: value DL: Delegates list LS: lifespan Giancarlo Ruffo, Schifanella Rossano, Università di Torino (Italy)

FairPeers: Purchasing an Item from an Owner X Owner {I want idf}SKX {Cert(f)}SKA {credits A for Ca(f)}SKX {License(f,X)}SKA {credits A for Cd(f)}SKX f Giancarlo Ruffo, Schifanella Rossano, Università di Torino (Italy)

FairPeers: Purchasing an Item from a Distributor X Y Owner {I want idf}SKX {License(f,Y)}SKY {credits A for Ca(f)}SKX {License(f,X)}SKA {License(f,X)}SKA {credits Y for Cd(f)}SKX f Giancarlo Ruffo, Schifanella Rossano, Università di Torino (Italy)

FairPeers: Purchasing an Item from Many Distributors Modern peer-to-peer systems allow multi-source downloads Trivial solution: all the sources must be payed. Performance deterioration (presence of a bunch of money transfers) Infeasible to manage pico-payments Lottery mechanism [Rivest, 1997]: instead of paying a fraction of distribution cost to all the distributors, only the lottery winner will gain all the value. Giancarlo Ruffo, Schifanella Rossano, Università di Torino (Italy)

{I want idf}SKX {License(f,Yi)}SKYi {License(f,X)}SKA Y distributors set X Y1 Yω Yn Owner {I want idf}SKX {License(f,Yi)}SKYi {credits A for Ca(f)}SKX {License(f,X)}SKA {Y,winner indicator}SKX fi {The winner is Yω}SKX {credits Yω for Cd(f)}SKX

Conclusions Yes, P2P can significantly reduce costs, improve scalability, and distribute the profits This is technically feasible. Is there political and/or economic interest? The end of the DRM vs DRM-free debate may give new gasoline to P2P. Be ready to run! Social Networking and Viral Phenomena can be of great help for providing services and/or modeling the domain Please, address any further question to: ruffo@di.unito.it or schifan@di.unito.it Giancarlo Ruffo, Schifanella Rossano, Università di Torino (Italy)