Trust-Based Fast Inter-Domain Secure Handoff over Heterogeneous Wireless Networks

The emerging 3G-WLAN heterogeneous networks are attracting technologies for the next generation wireless communication system. A challenging issue for the technologies is how to reduce the secure handoff delay when users roam across multiple domains. Generally, the re-authentication procedure in a visited domain causes a large delay during a secure handoff that always involves communication with the home domain. Most existing solutions are based on pre-authentication between the different domains, which needs to statically build the roaming agreement between each pair of domains, and can not support dynamic and flexible co-operation for them. In this paper, we propose a fast authentication scheme, named as T-FISH, based on a trust-token mechanism to reduce the secure handoff delay. A trust-token is issued by the home domain or a visited domain, and uses attribute-based encryption (ABE) cryptography to encrypt key information. A mobile user with a trust-token can authenticate directly in a visited domain for fast handoff. The proposed scheme can realize a fine-grained access control and a scalable cooperation business model for wireless service providers (WSPs). To the best of our knowledge, this is the first secure handoff scheme based on the ABE cryptography. The analysis and evaluation show that the proposed scheme can effectively reduce the re-authentication delay without reducing the level of security, and it securely and dynamically extends the cooperation relationship between WSPs.