I attended the second cryptography meetup at Cloudflare last Wednesday and was once again impressed by the turnout. It was only the second talk and they’ve already had prominent members of the crypto community speaking including Adam Langley from Google, Trevor Perrin who worked on TextSecure and Brian Warner from Mozilla.

The talks were all fantastic but Trevor’s talk about application level encryption and the challenges of group encryption the most interesting. The challenge is that there’s no known protocol or algorithm for generating a shared secret key among more than two individuals, although there has been recent research on the subject. Additionally, TextSecure had some requirements specific to the asynchronous nature of messaging and didn’t introduce any new primitives to accomplish their goal. They instead use racheting for key exchange and forward security which allows them to avoid establishing a session between users.

All the talks from the first round can be found on Cloudflare’s YouTube channel, and I expect the second round will be added before too long.

I’m looking forward to the next set of talks as I’ll surely be attending them.