In one embodiment, a method can include: receiving rules in an interoperability server, the rules being related to access control for an endpoint coupled to a variable source content stream via a multicast network; and sending to the endpoint using in-band controls of the variable source content stream via the multicast network: a description of content streams available for selection by the endpoint; a procedure for selecting an available content stream; and permission for accessing the selected content stream, the permission being based on the rules.