Remodel an existing peer to peer Bit Torrent project in java

In this project, you are asked to remodel/rewrite an existing P2P file sharing software similar to BitTorrent in Java. BitTorrent is a popular P2P protocol for file distribution. Among its interesting features, you are asked to implement the choking-unchoking mechanism which is one of the most important features of BitTorrent. In the following Protocol Description section, you can read the protocol description, which has been modified a little bit from the original BitTorrent protocol.