I need to create a server that will receive an encrypted/signed message in form of a http request (Google App Engine), decrypt it/check the signature, and send it over a TCP/IP connection (Bitcoin network). Moreover, it will need to do the same in reverse - receive TCP/IP messages, encrypt/sign them, and send them as a http request. I'm planning to put the server on EC2.
I don't have too much experience with these things, so I'd like to ask - what is the easiest programming language to create something like that in, and what libraries would you recommend for the required usability?