nTorrent: Peer-to-Peer File Sharing in Named Data Networking

BitTorrent is a popular application for peer-to-peer file sharing in today’s Internet. In the core of BitTorrent is a data-centric data dissemination approach, where peers request pieces of the file(s) from each other, and each retrieved piece can be verified using cryptographic hashes. This process looks similar to that of the Named Data Networking (NDN) architecture, but is realized completely at the application level on top of the channel-based TCP/IP networking. Consequently BitTorrent has to maintain an overlay network of peers, discover and share IP addresses of peers, keep track the quality of established connections, and incentivize other peers to share data. This paper presents the design of nTorrent, a BitTorrent-like application that is based on the natively data-centric NDN network architecture. Through analysis and simulation-based experimentations, the paper exposes impacts of the network-level data-centricity on the design choices, implementation complexity, and protocol operations.