Building a BitTorrent client from the ground up in Go (2020) (blog.jse.li)

Article summary

The article describes the process of building a BitTorrent client from scratch in Go, covering topics such as finding peers, parsing .torrent files, and downloading pieces from peers. The author implements the original BitTorrent spec from 2001 and uses a Debian ISO file as a test case. The client is able to connect to a tracker, retrieve a list of peers, and download pieces from them. However, the implementation only covers the downloading part and does not include uploading or sharing pieces with other peers.

Main themes

• BitTorrent protocol
• Go programming language
• Peer-to-peer networking
• Decentralization
• File sharing
• Networking fundamentals
• Protocol implementation

What commenters say

• The article provides a valuable learning resource for those looking to understand how BitTorrent works and how to implement it in Go.
• The lack of upload and sharing functionality in the implementation is a significant limitation.
• Decentralization is an important aspect of BitTorrent and other peer-to-peer protocols, and it is essential to understand how they work.
• Some commenters believe that BitTorrent is still a relevant and useful protocol, while others think it is waning in popularity.
• The article's focus on the downloading part of the protocol is seen as a limitation by some, who believe that uploading and sharing are essential components of a fully functional BitTorrent client.
• The use of DHT and other decentralized peer discovery methods is an important aspect of BitTorrent that is not fully explored in the article.
• The implementation of BitTorrent in Go is seen as a useful exercise in learning about the protocol and the language.
• Some commenters disagree about the importance of decentralization and the relevance of BitTorrent in modern internet architecture.