Hyun Gon Kim

Secure session key exchange for mobile IP low latency handoffs

Mobile IP Low Latency Handoffs[1] allow greater support for real-time services on a Mobile IPv4 network by minimising the period of time when a mobile node is unable to send or receive IP packets due to the delay in the Mobile IP Registration process. However, on Mobile IP network with AAA servers that are capable of performing Authentication, Authorization, and Accounting(AAA) services, every Regional Registration has to be traversed to the home network to achieve new session keys, that are distributed by home AAA server, for a new Mobile IP session. This communication delay is the time taken to reauthenticate the mobile node and to traverse between foreign and home network even if the mobile node has been previously authorized to old foreign agent. In order to reduce these extra time overheads, we present a method that performs Low Latency Handoff without requiring further involvement by home AAA server. The method re-uses the previously assigned session keys. To provide the confidentiality of session keys in the phase of key exchange between old FA and new FA, it uses a key sharing method with a trusted third party. The proposed method allows the mobile node to perform Low Latency Handoff with fast as well as secure operation.

Session Key Exchange Based on Dynamic Security Association for Mobile IP Fast Handoff

For Low Latency Handoffs(LLH) [1] to be fast and effective, the Mobile IP session keys distributed by home AAA(Authentication, Authorization, and Accounting) server should be reused [2]. This can decrease the number of signaling messages to the home network, and reduce the signaling delay when a mobile node moves from one foreign agent to another, within the same visited domain. To reuse the session keys in a secure fashion, we present a method that performs the LLH without requiring further involvement by home AAA server. To prevent session stealing attack, the method provides the confidentiality and integrity of session keys in the phase of key exchange between old foreign agent and new foreign agent by using Diffie-Hellman key agreement. It allows the mobile node to perform LLH with fast as well as secure operation.

Analysis and design of secure and reliable transmission protocol in diameter

Diameter adopts TLS to secure transferring messages between communicating peers and defines TCP and SCTP as its transmission protocol. This paper analyzes functional requirements of transmission protocol of Diameter and proposes design of transport layer structure including integrated TLS with SCTP. First, we analyze the functional requirements of transport protocol both TCP and SCTP in Diameter as well as TLS. To integrate TLS and SCTP, we analyze characteristics of TLS and SCTP. Based on their characteristics, we derive design requirements of transport layer structure integrated TLS and SCTP.