A transaction protocol for communicating between an encryption renewal system communicably coupled to one or more video on demand systems via a communication network. The encryption renewal system permits pre-encrypted content to be accessed by clients of the video on demand systems. The protocol comprises, receiving, by the encryption renewal system, a request transaction document having a first format from the video on demand system; parsing the request transaction document to retrieve data from the request transaction document; generating a request object code in a second format for processing by encryption renewal system, the request object code based on the data in the request transaction document; responsive to processing of the request object code, generating a response object code having the second format; converting the response object code to a response transaction document having the first format; and forwarding the response transaction document to the video on demand system.