1. A method of granting a client access to a communication network, the method comprising: blocking access by the client to the communication network using an enforcer; receiving a request to access the communication network from the client; invoking an appropriate access protocol terminator; receiving at least one attribute associated with client access to the communication network from the appropriate access protocol terminator; translating the at least one attribute into a canonical form; receiving at least one attribute of backend service type information and translating the at least one attribute of the backend service type information into the canonical form; using the at least one attribute associated with client access in canonical form and the at least one attribute of the backend service type information in canonical form as input to policy rules; applying the policy rules to determine a policy result; delivering the policy result to the enforcer; and granting access by the client to the communication network through the enforcer based on the policy result.