Date: 2004/02/02 15:30-17:00

      Place: Lecture Hall (Knowledge Science Building)

      Name: Kwangjo KIM
           Director of IRIS
           Prof. of ICU (Information and Communications Univ.)

      Title: An Efficient Tree-based Group Key Agreement using Bilinear Map

      Secure and reliable group communication is an increasingly active research area by growing popularity in group-oriented and collaborative application. One of the important challenges is to design secure and efficient group key management. While centralized management is often appropriate for key distribution in large multicast-style groups, many collaborative group settings require distributed key agreement. The communication and computation cost is one of important factors in the group key management for Dynamic Peer Group. In this paper, we extend TGDH (Tree-based Group Diffie-Hellman) protocol to improve the computational efficiency by utilizing pairing-based cryptography. The resulting protocol reduces computational cost of TGDH protocol without degrading the communication complexity.

      Title: Practical Solution for Location Privacy in Mobile IPv6

      Mobile IP protocol (MIP) enables the Mobile Node (MN) to move around without loosing their transport-layer connectivity by using resources in the foreign domain network. MIP is currently a hot research area and expected to be the core infrastructure of future mobile communication. However, a certain level of security services must be provided before the wide deployment of MIP. Security services, such as authentication and access control of the MN, have been considered since the birth of MIP. But little attention has been given to location privacy service, i.e. preventing the tracing of mobile user's point of attachment to the network, despite of their increased significance in wireless network. The disclosure of a MN's location and identity allows unauthorized entities to track down his moving history, which can be a serious violation of privacy. We identify required level of location privacy, and propose an efficient protocol for providing the identified level of location privacy. We also examine that this protocol is compatible with current IPv6 and MIPv6 specifications.