Incentives - Peer-to-Peer Computing: Applications, Architecture, Protocols, and Challenges - page 127

5.6 Summary
In this chapter, we have presented a detailed survey of incentive tech-
niques for promoting sharing (discrete or continuous data) in a peer-to-peer
system. We have considered well-known mechanisms that are proposed and
have been deployed on the Internet environment. The techniques used can be
classified into: payment based, exchange based, reciprocity, reputation, and
game theoretic. These techniques are also applicable in general to a wireless
environment. However, a wireless P2P system, while still in its infancy, has a
unique challenge—the connectivity among devices is by itself a crucial “shar-
ing” problem (sharing of energy and bandwidth). Much more work needs to
be done in related problems such as revenue maximizing (or pricing) in a hy-
brid wireless P2P system, intelligent peer selection in a data sharing network,
energy aware incentive mechanisms, and interest-based topology control. Fur-
thermore, in systems that require payments or some form of critical informa-
tion items (e.g., reputation values), the security aspect needs to be properly
addressed.
Finally, we can see that the amounts of work done in the areas of media
streaming and wireless P2P systems are much smaller than that in the area
of file sharing. This indicates that these two areas are wide open and are a
fertile ground of further research.
5.7 Review Questions
1. What are the different categories of incentive schemes?
2. What are the drawbacks of a payment-based system?
3. What are the main features of BitTorrent's incentive scheme?
4. What are the special incentive requirements for a media streaming sys-
tem?
5. What are the di culties involved in enforcing cooperation in a wireless
P2P system?
6. What are the adverse effects from the lack of an effective incentive
scheme?