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Meeting with Bram Cohen

During PyCon Sprints, I met Bram Cohen 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 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 - 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 uTP 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.