TK-AKA: using temporary key on Authentication and Key Agreement protocol on UMTS

Mobile communication is definitely one of the major high-technology applications that offer present-day people a modern life of appropriate convenience. In recent years, the third generation cell-phone system has approached maturity. The Universal Mobile Telecommunication System (UMTS) is currently the most widely used system around the world. The 3rd Generation Partnership Project is equipped with the Authentication and Key Agreement (AKA) protocol to maintain secret and secure both during the authentication process and during the telecommunication session through UMTS. However, Hung and Li have pointed out that the UMTS-AKA protocol has three problems involving the bandwidth consumption, space overhead, and synchronization of the sequence number that are yet to be resolved. In addition, they have proposed an extension of the UMTS-AKA protocol, named the X-AKA protocol, to overcome these obstacles. Nevertheless, the X-AKA protocol too appears to have problems of its own. In this article, the weaknesses of XAKA are enumerated. In addition, a more practical AKA protocol for UMTS is presented. The new protocol, based on the same framework as its predecessor, proves to be more efficient and practical, satisfying the requirements of modern living.