I'm creating a simple web service in PHP to serve data to some of our internal applications.
My question is around authentication/security, the implementation of the actual web service isn't a problem.
For security, I'm planning on providing each application that will be consuming the service with a unique, periodically static authentication code that they use when call into the service. The service code then checks an internal list to see if the authentication code being used is a valid one, and provides access to the data if it is.
E.g.
xxx.xxx.com/ws.php?op=getproductnameslist&authcode=329cj32x21xdd332
The service is being served over HTTPS, so transmission of the actual data should be encrypted.
I'd like some comments on the above in terms security concerns, and if there is a better way to do this.