• Proceedings of the Korean Institute of Communication Sciences Conference
• /
• 2006.07a
• /
• pp.214-214
• /
• 2006

• 한국IT서비스학회:학술대회논문집
• /
• 2008.05a
• /
• pp.590-593
• /
• 2008

본 논문에서는 SIP 기반의 VoIP 서비스에서 발생 가능한 스팸 위협중 도청을 이용하여 Redirect 서버에서 Proxy 서버로 송신되는 패킷을 불법적으로 위 변조하여 공격하는 기법의 시나리오와 이를 차단하기 위해 발신자 인증 기법을 제안하였다. UAC가 상대편 UAS에게 INVITE 메시지를 송신할 때 Proxy 서버에서 UAS와 연결되어 있는 Proxy 서버의 주소를 알지 못한다면 Redirect 서버에서 질의를 해야 하는데 그때 Redirect 서버는 302 메시지에 Proxy 서버가 요청한 주소를 실어 보내게 된다. 이 302 메시지 패킷을 스패머가 위 변조 할 경우 Proxy 서버는 잘못된 주소가 포함된 INVITE 메시지를 생성하게 되고 스패머와 RTP 세션이 열릴수 있다. 따라서 본 논문에서는 이를 차단하기 위해 인증 메시지가 포함된 ACK 메시지를 정의하여 인증 시스템을 설계하였다.

• The Journal of Korean Institute of Communications and Information Sciences
• /
• v.32 no.12B
• /
• pp.750-757
• /
• 2007

This paper analyzes spam threats and proposes key exchange scheme for user authentication and SDP encryption to protect potential spam threats in SIP-based VoIP services. The existing HTTP digest authentication scheme exchanges many message because challenge is sent for every establishment of the session and doesn't provide a confidentiality of SDP. To protect SPIT, our scheme exchanges initial nonce and a session master key for authentication and SDP encryption during registration. In our scheme, the challenge and response procedure is not necessary and the communication overhead is much less than applying S/MIME or TLS.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
• /
• 2011.10a
• /
• pp.237-240
• /
• 2011

Voice over Internet Protocol calls using administrative agency to build a national information and communication service, 'C' group, providers, the KT, SK Broadband, LG U+, Samsung SDS, as there are four operators. To prepare for an attack on Voice over Internet Protocol for administrative agency, security is a need for research to support the model. In this paper, the Internet telephone business of Administrative Agency to investigate and analyze the specific security measures to respond. Should set priorities around confidentiality about five security threats from NIS to Study of Voice over Internet Protocol Security Response Model for Administrative Agency. (1) Illegal wiretapping, (2) call interception, (3) service misuse, (4) denial of service attacks, (5) spam attacks, write about and analyze attack scenarios. In this paper, an analysis of protection by security threats and security breaches through a step-by-step system to address the research study is a step-by-step development of the corresponding model.