Open problem of p2p

<Open problems in Data sharing peer-to-peer systems>

Requirements of a p2p syutem can be specified in 3 main categories: Expressiveness, comprehensiveness, automony.

1. Expressivness. simple key lookup, keyword queries,(ranked keywords, aggregates) complex SQL  queries.

2. Autonomy, efficiecy and robustness tradeoff between them.

Qos related to number of results, response time and results' relevance.