digest authentication with secret / public key

Question

I'm working on providing some data to clients via API and have been examining various ways to authenticate requests. It looks like digest authentication will be the best route, since I can't be sure that the server will offer SSL, and there's no need for serious security.

I've worked (as a client) with plenty of APIs in the past including:

• Amazon AWS that use a key pair (public key, secret key)
• Facebook that use app ID and key, (application ID, secret key)

Is there a general method to how these systems work? Is there a name for this technique, or is this some variant on digest authentication?

Thanks

Answer 1

From what I can tell of your explanation, you are looking for digital signature.