I'm looking to create a licensing system, and I need a serial generation scheme. I want to sign some data with a private key and verify it with a public key embedded in the software.
I don't need something that is easily typable, only easily copyable. The shortest I've gotten to is 56 base64 characters using DSA signing.
Can I get a shorter key? Functionality here is much more important than security, though it needs to be non trivial.