Patent ID: 8533458

Claim:
A method of operating a headend system for a downloadable conditional access service, the method comprising: receiving, by an Authentication Proxy (AP) server, basic authentication information from a Downloadable Conditional Access System (DCAS) host, the basic authentication information being required to authenticate the DCAS host; transmitting, by the AP server, the basic authentication information to an external trusted authority device which authenticates the DCAS host, wherein after the DCAS host in authenticated, the DCAS host is able to communicate with the AP server, wherein after the external trusted authority device authenticates the DCAS host and DCAS host communicates with the AP server, the external trusted authority device generates a session key sharing factor; transmitting, by the external trusted authority device, the session key sharing factor to the AP server, wherein the AP server receives and shares the session key sharing factor with the DCAS host, wherein, after sharing the session key sharing factor with the DCAS host, the DCAS host and the AP server perform mutual authentication based on the session key sharing factor, wherein, after the mutual authentication between the DCAS host and the AP server has been completed, generating by each of the AP server and the DCAS host a session key, and wherein the generating step of the session key, by the AP server and the DCAS host, the session key allows for encrypting/decrypting a secure micro client by the IPS and the DCAS host, wherein the generating step of the session key, by the AP server and the DCAS host, the session key allows for encrypting/decrypting a DCAS message by the AP server and the DCAS host, wherein the session key for both encrypting/decrypting the secure micro client by the IPS and the DCAS host and encrypting/decrypting the DCAS message by the AP server and the DCAS host is generated by each of the AP server and the DCAS host, wherein the session is generated based on the session key sharing factor generated from the external trusted authority device after the external trusted authority device authenticates the DCAS host and DCAS host communicates with the AP server, and wherein the session key generated by the AP server and the session key generated by the DCAS host are a same session key.