@jwildeboer if the NSA can monitor all traffic going in and out (they can) then they don't need a subpoena
@powersource
It would be easy as well as signal is using aws, Google, cloudflare and azure. They also use twilio for SMS messages I think. All those companies could easily collaborate and provide information on which IP address is talking to signal servers and when. So be careful of your threat model. This could be used to confirm suspects are talking to each other for example. Even sealed sender is not always useful. Signal is a good solution but it has limitations.
@jwildeboer