Han-Seung Koo

A novel protocol for downloadable CAS

This paper presents a novel protocol for downloadable conditional access system (DCAS) which can securely download conditional access (CA) software via bidirectional communication channel. The proposed DCAS protocol uses pre-assigned keys and certificates for mutual authentication between a DCAS headend and DCAS host, and then it shares a session key for encrypting and decrypting CA software to be downloaded to a DCAS host. In order to verify the stability and effectiveness of the proposed protocol, we implement the DCAS protocol simulator. It can emulate the function of DCAS entities and the process of messages for mutual authentication, session key sharing and code downloading. Finally, experimental results indicate that the proposed protocol satisfies the design requirements for DCAS1.

A tree key graph design scheme for hierarchical multi-group access control

A tree key graph design scheme for hierarchical multi-group access control with low communication overhead is presented. A simulation result shows that the proposed scheme can reduce a communication overhead up to about 15.2% compared to the previously proposed scheme.

Key refreshment management for conditional access system in DTV broadcasting

This work presents a key refreshment management scheme for a conditional access system (CAS) in DTV broadcasting. The proposed scheme not only performs dynamic entitlement management securely and efficiently, but also reduces the key generation and encryption load for CAS.

Downloadable multi-CA/DRM service model and architecture for mobile broadcasting

Downloadable multi-CA/DRM is an emerging technology which has been standardizing in multiple standard organizations such as ITU-T and ETSI. This technology is used for providing multiple conditional access system and digital right management environment in pay-television service to overcome market fragmentation and enable interoperability. We studied a reference model and system architecture for downloadable multi-CA/DRM in mobile broadcasting service. It is also specified that the detail operational processes for downloadable multi-CA/DRM service.

An Active Entitlement Key Management for Conditional Access System on Digital TV Broadcasting Network

Conditional access system (CAS) performs entitlement management to make only legitimate subscribers watch pay-services. Generally, CAS uses passive entitlement management to fulfil that entitlement control, and various schemes are existed for that. Among them, Tu introduced two schemes in F.K. Tu et al., (1999), which are the simple scheme and complete scheme of four levels hierarchy. The advantage of the simple scheme of four levels hierarchy is a small key generation and encryption load for a CAS, but it is not good for the dynamic entitlement management. On the other hand, the complete scheme of four levels hierarchy is good for the dynamic entitlement management, but key generation and encryption load for CAS is considerable when it is compared to the simple scheme. In this circumstance, we proposed a novel scheme, which is an active entitlement key management. The proposed scheme not only performs the dynamic entitlement management very efficiently, but also generates and encrypts keys with a small load for CAS, which is just the same as the load of the simple scheme

A novel rekey management scheme in digital broadcasting network

Conditional Access System (CAS) performs entitlement management to make only legitimate subscribers watch pay-services. Generally, CAS uses passive entitlement management to fulfill that entitlement control, and various schemes are existed for that. Among them, Tu introduced two schemes in [1], which are the simple scheme and complete scheme of four levels hierarchy. The advantage of the simple scheme of four levels hierarchy is a small key generation and encryption load for a CAS, but it is not good for the dynamic entitlement management. On the other hand, the complete scheme of four levels hierarchy is good for the dynamic entitlement management, but key generation and encryption load for CAS is considerable when it is compared to the simple scheme. In this circumstance, we proposed a novel scheme, which is an active entitlement key management. The proposed scheme not only performs the dynamic entitlement management very efficiently, but also generates and encrypts keys with a small load for CAS, which is just the same as the load of the simple scheme.

Implementation of AR-Based Hybrid Broadcasting System by TV Viewer's Preferred Content Provider

This paper proposes a AR-based hybrid broadcasting system via broadcast and broadband networks under terrestrial DTV environment. Augmented Reality (AR) technology is a kind of mixed reality which 2D/3D graphics are integrated into the real world in order to enhance user experience and enrich information. A goal of AR-based hybrid broadcasting system is to enable broadcasting program using AR technology to blend augmented content (2D/3D graphic object) with broadcasting content in real-time on receiving terminals. The proposed system enables viewer-selectable augmented broadcasting service being provided from two content providers with authorization by a broadcaster and we show the implemented results under a terrestrial DTVs environment.

Service framework for public wireless electric charging

Wireless Power Transfer (WPT) is a technology of transferring electricity from the electric power source to other devices without the need of wired intermediate media such as cable and plugs. There are many standards developed to provide wireless power charging. With these technologies, it would be very effective if the public can provide wireless charging service to the mobile devices which can ease the burden in carrying extra batteries and electric adaptors. For this, public needs to provide service framework which consists of charging service control and management, reliable authentication/authorization, fare-charging policy, etc. This paper proposes service framework and service flow to be considered for proving wireless power transfer in the public space.

Smart agricultural framework over RCAS in CATV network

This paper proposed smart agricultural framework over RCAS in CATV network. The proposed framework adopts RCAS, which is a security system which is dedicated to cable television system, as a data protection system, and cable two-way broadband network as a communication channels among smart agricultural service participants.

A low overhead TEK rekeying scheme for IPTV CAS over DOCSIS 3.0

A novel scheme is presented for traffic encryption key (TEK) rekeying with low communication overhead for an Internet television (IPTV) conditional access system over Data-Over-Cable Service Interface Specifications (DOCSIS) 3.0. The proposed scheme utilizes the DOCSIS system synchronization for periodic TEK rekeying instead of a conventional TEK rekeying negotiation process. Analysis shows that the communication overhead is only 0.012 Kbps when TEK rekeying frequency is 1 second.