Peer exchange

Abstract: Peer Exchange (PEX), in which peers directly exchange with each other lists of active peers in the torrent, has been widely implemented in modern BitTorrent clients for decentralized peer discovery However, there is little knowledge about the behavior of PEX in operational systems In this paper, we perform both passive measurements and Planetlab experiments to study the impact and properties of BitTorrent PEX We first study the impact of PEX on the download efficiency of BitTorrent We observe that PEX can significantly reduce the download time for some torrents We then analyze the freshness, redundancy and spread speed of PEX messages Finally, we also conduct large- scale Planetlab experiments to understand the impact of PEX on the overlay properties of BitTorrent

Abstract: In this paper, we conduct extensive simulations to understand the properties of the overlay generated by BitTorrent. We start by analyzing how the overlay properties impact the efficiency of BitTorrent. We focus on the average peer set size (i.e., average number of neighbors), the time for a peer to reach its maximum peer set size, and the diameter of the overlay. In particular, we show that the later a peer arrives in a torrent, the longer it takes to reach its maximum peer set size. Then, we evaluate the impact of the maximum peer set size, the maximum number of outgoing connections per peer, and the number of NATed peers on the overlay properties. We show that BitTorrent generates a robust overlay, but that this overlay is not a random graph. In particular, the connectivity of a peer to its neighbors depends on its arriving order in the torrent. We also show that a large number of NATed peers significantly compromise the robustness of the overlay to attacks. Finally, we evaluate the impact of peer exchange on the overlay properties, and we show that it generates a chain-like overlay with a large diameter, which will adversely impact the efficiency of large torrents.

Abstract: Extension Forestry has long acted as a medium for landowner education and engagement through a variety of programs that encourage peer learning. We describe recent trends and innovations in Extension Forestry programming by reporting the results of surveys and focus groups with the managers of 39 (of 42 identified) Extension Forestry master volunteer and other peer-learning programs. These programs combine instruction from experts with peer learning and volunteerism to provide nonformal adult education for family forest owners. Results indicate that Extension Forestry peer-learning programs are evolving to address emerging issues and to use recent developments in communication and educational technologies, such as online programming and social media. With median annual budgets of just over $10,000, several programs target small and often underserved segments of the landowner population, such as women and absentee landowners. Although program outputs and demands for service are increasing, many program managers face reduced budgets and a variety of challenges to program sustainability.

Abstract: An approach for enabling autonomous decentralized peer-to-peer telemetry (ADEPT). A first ADEPT peer senses ADEPT peers to interconnect where the ADEPT peers are identified as ADEPT light peer, ADEPT standard peer and ADEPT peer exchange based on respectively increasing IoT device capability. The first ADEPT peer sends and receives requests to interconnect to the ADEPT peers based on messaging. The first ADEPT peer transfers files where the files are distributed toward peer-to-peer networks, creating peer consensus and interconnecting the first ADEPT peer to the ADEPT peers based on the peer consensus. ADEPT peers execute transactions and contracts by decentralized peer to peer consensus network and consensus ledger to enable autonomous device coordination.