Meeting with Bram Cohen

During PyCon Sprints, I met Bram_Cohen Bram Cohen is an American computer programmer, best known as the author of the peer-to-peer (P2P) BitTorrent protocol in 2001, as well as the first file sharing program to use the protocol, also known as BitTorrent. He is also the co-founder of CodeCon and organizer of the San Francisco Bay Area P2P-hackers meeting, was the co-author of Codeville and creator of the Chia cryptocurrency which implements the proof of space-time consensus algorithm. who had come down to talk to Guido and have a word on networking protocol world. It was interesting to see two experts talking. Later I invited Bram to give a tech talk at Twitter. Bram gladly accepted it and came to Twitter office to talk to us about his latest invention http://live.bittorrent.com He had been working on Distributed Live Streaming for few years and thought it was a hard problem to solve. He could dedicate himself to it and came out with live.bittorrent.com - Using this anyone can live stream a video. You can become a live video publisher too and people all around the word can see your channel in real time. This is a huge break through. My experience at Akamai helps me realize the kind of break through this can bring to real time live streaming.

Bram went with the technical aspects of the design of the live bittorrent technology and how to keep the delays as minimum as possible. He was talking at the network packets level and explaining how the packets need to be distributed from one node to another so that delay can be as minimum as possible and what are the bottlenecks that exist during the packet transfer. The innovative solutions that he had use to make these possible. He started by giving a pitch to Dan Bernstein's ciphers and explained about the TCP handshake and udp transfers and how Micro_Transport_Protocol Micro Transport Protocol (μTP, sometimes uTP) is an open User Datagram Protocol-based (UDP-based) variant of the BitTorrent peer-to-peer file-sharing protocol intended to mitigate poor latency and other congestion control problems found in conventional BitTorrent over Transmission Control Protocol (TCP), while providing reliable, ordered delivery. goes in the background during transfers and not affect peak real time traffic. The details could by got only if I read through his spec a couple of times.

One interesting thing that struck me was. One engineer asked the question, "how did he test his development of live bittorrent system?". Bram got excited to share his valuable experience in doing that. He said, few years ago he made a point saying "Remove all psychic powers in software development" - by this he meant, remove all assumptions that a software will work "magically", "assume" that it work under all conditions, but rather encode the scenarios and simulate all the possible scenarios under which you want your software to work and then run your software through it. To this effect, he seemed to built a small simulator which can help him test the system. That was a good learning and major take away for me from this session.