Overlay Convergence Analysis in P2P Networks: An Assessment of the 2PC Algorithm
Adriel Cardoso dos Santos, Cristiano M. Silva, Eliseu Cesar Miguel · 2020
Peer-to-Peer (P2P) Networks for live streaming require low latency and low discontinuity in media transmission among peers. When latency is high, multiple users watch the video at different times, and in the case of high discontinuity, various parts of the media are not viewed by network users. Also, other factors compromise the quality of service of a P2P network of live streaming, such as the presence of a large number of peers that do not contribute to the distribution of the media, known as free riders, and the constant arrival and departure of peers during transmission, known as peer churn. An alternative to preserve the quality of a P2P network of live streaming is the usage of algorithms for construction and maintenance of the overlay network. One of these algorithms is the Peer Classification for Partnership Constraints (2PC), proposed to allow a large number of free riders in the network. 2PC acts by imposing constraints on partnerships between peers according to their contributions in the media transmission. 2PC was successfully tested on PlanetLab and its authors states the algorithm attracts high-contribution peers close to the server, while pushes low-contribution peers to the edge of the overlay. However, the authors have not demonstrated that this peer organization in the overlay actually happens. In this work, by analyzing the logs of the execution of the 2PC algorithm, together with the application of graph structures, we evaluated the application of the 2PC and identified that the partnership relationships between peers imposed by the algorithm organizes the overlay as expected.