Abstract: Provided are a Downloadable Conditional Access System (DCAS), and a channel setting method and a message format for a 2-way communication between a terminal and an authentication server in the DCAS. The DCAS may include: a verification unit to verify an electronic signature and an integrity with respect to a message received from the authentication server; an extraction unit to extract network access information of the authentication server from the message in which the electronic signature and the integrity are verified; and a channel setting unit to set a communication channel with the authentication server based on the extracted network access information.

Abstract: A method of processing a call to an unregistered user in a Wireless Local Area Network (WLAN)-General Packet Radio Service (GPRS) using a Session Initiation Protocol (SIP) is provided. The method of connecting a call to a mobile node present in a GPRS area includes registering location information of the mobile node to be invited in a Home Subscriber Server (HSS); when the mobile node uses a Mobile Internet Protocol (MIP), allocating an Internet Protocol (IP) address to the mobile node and authenticating the mobile node through MIP registration and setting a SIP session; and when the mobile node uses a simple IP, allocating an IP address to the mobile node and authenticating the mobile node through a Dynamic Host Configuration Protocol (DHCP) procedure and setting a SIP session.

Abstract: An automatic roaming apparatus and method of a terminal in a digital cable broadcasting network is provided. The method includes: performing device authentication of the terminal when terminal authentication is requested by the terminal; verifying whether roaming authentication of the terminal having requested the terminal authentication is required; requesting subscriber authentication for a Provisioning Server (PS) in a home domain and receiving the subscriber authentication when the terminal exists in the home domain, when the roaming authentication of the terminal is verified as being required; transmitting a result of the device authentication and the subscriber authentication as a response to the terminal; and instructing an Integrated Personalization Server (IPS) to download a Conditional Access (CA) application to the terminal.

Abstract: A method and apparatus of supporting a fee-based broadcasting service in a Downloadable Conditional Access System (DCAS) is provided. A control method of a DCAS, the method including: receiving a Conditional Access (CA) image file from a Conditional Access System (CAS) server and receiving Integrated Personalization Server (IPS) access information from an IPS; providing an Authentication Proxy (AP) with information about the received CA image file; controlling the AP to provide a terminal with access information to the IPS and image installation information when the terminal joins a fee-based service based on verifying device information of the terminal; and controlling the IPS to enable the terminal to receive a CA image code of the terminal based on the access information and the image installation information.

Abstract: Disclosed is a mutual authentication method and apparatus in a CAS including a headend system and DCAS host. In particular, example embodiments relate to a mutual authentication method and apparatus in DCAS, wherein the mutual authentication is performed between an authentication server of the headend system and an SM of a DCAS host, and then CAS software is downloaded to the SM. According to the example embodiments, there is provided a mutual authentication protocol between the authentication server of the headend and the SM of the DCAS host in a cable network, and also provided a mutual authentication method and apparatus in the DCAS where a substantial authentication based on a hardware, such as a smart card or a cable card, is not needed.

Abstract: A method and apparatus for management and transmission of a classified conditional access application to provide Downloadable Conditional Access System (DCAS) service according to disclosed embodiments is an effective managing method according to a type of a conditional access module in a software version in the DCAS. In particular, it relates to a method and apparatus which can continuously provide Pay per View (PPV) service during movement in a DCAS service operator (SO) network, such as maintaining independence of CAS SO in DCAS, provide adaptability to adapt to a variety of policies of the SO, and install an optimum application in a terminal.

Abstract: A method and apparatus of X.509 certificate-based mutual authentication and key distribution for a Downloadable Conditional Access System (DCAS) in a digital cable broadcasting network is provided for composing a software-based secure DCAS in various Conditional Access Systems (CASs) based on an embodiment form of Conditional Access (CA) application for CA of digital cable broadcasting.

Abstract: A method of operating a headend system for a downloadable conditional access service, the method including: 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; generating, by the AP server, a session key for encrypting/decrypting a secure micro client using a session key sharing factor; obtaining, by the AP server, download-related information of the secure micro client from a DCAS Provisioning Server (DPS); and commanding, by the AP server, an Integrated Personalization System (IPS) server to download the secure micro client to the DCAS host based on the download-related information, the secure micro client being encrypted by the session key.

Abstract: A method for supporting handoff and preventing data loss in mobile communications networks is provided.