It’s worth reading the mailing list posts by BITS (the main proponent of ETS) here: https://mailarchive.ietf.org/arch/msg/tls/KQIyNhPk8K6jOoe2Sc... . The replies are pretty informative. You can see here the message in which BITS starts to consider fixed DH keys, which were implemented in ETS: https://mailarchive.ietf.org/arch/msg/tls/3d7TM0g_EdtMzhgmcP... > Tue, 27 September 2016 18:21 UTC > The various suggestions f…
If you think about it, given the retention requirements they have, it's not clear that forward secrecy is useful in that context.
If they're actually recording the entirety of every TCP stream that comes into the datacenter, how many sets of credentials do you think are stored in that system? And right now, they're all encrypted with a single or small number of keys, that must be available to the system that is storing and parsing this data.
Also, given the breaches that have happened, I keep waiting for there to be a set of regulations from the other side requiring adequate protection and deletion of data. He seems entirely unconcerned with that aspect.