Hak-soo Ju

CAS-based Security System for IPTV

ABSTRACT IPTV is well known services of TPS (Triple play service). Since TPS supplies the bundle service, service providers can supply low-priced services for their subscribers. To supply high quality contents stably, it is an essential requirement to make payment for the services. According to the type of services, either CAS or DRM is used to protect the pay-contents service. Also IPTV uses or will use these security systems to protect the service. In this paper, we will describe security problems when a IPTV service provider chooses either CAS or DRM, and then propose a new security system to solve the problems. Key Words: IPTV, CAS, DRM 1. 서 론 1) TPS (Triple Play Service)는 방송, 통신 그리고 데이터 서비스를 하나의 서비스로 구성하여 제공하는 융합 서비스로 IPTV는 TPS의 대표적인 예다. IPTV 서비스는 주문형 서비스(Video on Demand, VoD) 뿐만 아니라 방송 서비스를 인터넷 환경에서 제공할 수 있다는 장점 때문에 다양한 소비 계층의 욕구를 만족시킬 수 있을 것으로 기대되고 있다 [1] . 그러나 이와 같은 서비스의 발전은 콘텐츠의 불법 복사 및 배포라는 새로운 문제에 직면했다. 그러므로 서비스 제공자(Service Provider, SP)가 고품질의 콘텐츠를 안정적으로 공급하기 위해서는 콘텐츠 사용 제어 및 요금 징수를 위한 보안 시스템이 반드시 필요하다. 콘텐츠 보호 및 사용

Clone resistant mutual authentication using two broadcast encryption

This paper provides a clone resistant mutual authentication between Secure Digital (SD) memory cards and host devices. The existing mutual authentication using one broadcast encryption can not resist cloning attacks. Therefore, a new clone resistant mutual authentication is proposed by using two broadcast encryption with the traitor tracing algorithm.

A Study On Forward Secure Mediated RSA Digital Signature

Many service systems use Public Key Infrastructure (PKI) to protect the service. But there arc problems with the use of PKI. One of the problems is that some services would require a function instantaneously to check public kel certificate, but PKI does not satisfy such request. To solve the problem, Bouch et al. first proposed the concept of mediated RSA (mRSA). Then Gene Tsudik proposed `weak` forward secure mRSA. In this paper, we analyze the weakness of these schemes and find the source of the vulnerabilitv. And we propose a new mRSA that is strong forward secure.