Probabilistic Proximity-aware Resource Location in Peer-to-Peer Networks Using Resource Replication

Nowadays, content distribution has received remarkable attention in distributed computing researches and its applications typically allow personal computers, called peers, to cooperate with each other in order to accomplish distributed operations such as query search and acquiring digital contents. In a very large network, it is impossible to perform a query request by visiting all peers. There are some works that try to find the location of resources probabilistically (i.e. non-deterministically). They all have used inefficient protocols for finding the probable location of peers who manage the resources. This paper presents a more efficient protocol that is proximity-aware in the sense that it is able to cache and replicate the popular queries proportional to distance latency. The protocol dictates that the farther the resources are located from the origin of a query, the more should be the probability of their replication in the caches of intermediate peers. We have validated the proposed distributed caching scheme by running it on a simulated peer-to-peer network using the well-known Gnutella system parameters. The simulation results show that the proximity-aware distributed caching can improve the efficiency of peer-to-peer resource location services in terms of the probability of finding objects, overall miss rate of the system, fraction of involved peers in the search process, and the amount of system load

On Scalability of Proximity-Aware Peer-to-Peer Streaming

Abstract — P2P (peer-to-peer) technology has proved itself an efficient and cost-effective solution to support large-scale multi-media streaming. Different from traditional P2P applications, the quality of P2P streaming is strictly determined by performance metrics such as streaming delay. To meet these requirements, previous studies resorted to intuitions and heuristics to construct peer selection solutions incorporating topology and proximity concerns. However, the impact of proximity-aware methodology and delay tolerance of peers on the scalability of P2P system remains an unanswered question. In this paper, we study this problem via an analytical approach. To address the challenge of incorporating Internet topology into P2P streaming analysis, we construct a H-sphere network model which maps the network topology from the space of discrete graph to the continuous geometric domain, meanwhile capturing the the power-law prop-erty of Internet. Based on this model, we analyze a series of peer selection methods by evaluating their performance via key scalability metrics. Our analytical observations are further verified via simulation on Internet topologies. I