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

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

3. 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)

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

5. 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)

6. 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)

7. 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)

8. 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)

9. 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)

10. FairPeers: Purchasing an Item from an OwnerX
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)

11. FairPeers: Purchasing an Item from a DistributorX 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)

12. 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)

13. {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

14. 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: or
Giancarlo Ruffo, Schifanella Rossano, Università di Torino (Italy)