By signed request I mean something like this (simplified example):
Client creates a sig in his request:
$sig = hash('sha256', $api_key.$data); which generates
7409ur0k0asidjko2j for example. He then sends this to his request:
Now, the receiving server then performs the exact process to perform a match for the sig.
Which is generally more secure, a signed request like this or an HTTP digest auth for the purpose of authenticating requests to an API server? Note we assume SSL is not installed.