Security Enhanced Authentication and Key Agreement Protocol in Evolved Packet System

Abstract

The convenience of mobile network makes it an indispensable part of modern life. A lot of important information are transferred within the mobile network and should be well protected. However, there are still several vulnerabilities in the Evolved Packet System Authentication and Key agreement (EPS AKA) protocol for the LTE-A network as defined in the previous related works, such as sending the International Mobile Subscriber Identity (IMSI) in clear-text causing exposure of user identity and further causing user location tracing, man-in-the-middle(MITM) attack, replay attack, etc. Hence, in this thesis, a novel EPS AKA protocol is proposed to address these issues. A novel mechanism, named Dynamic Pseudonym Mechanism (DPM), is proposed to address the IMSI exposure, MITM attack and replay attack issues between User Equipment(UE) and Mobile Management Entity (MME). Compared with ciphering IMSI using Public Key Cryptography (PKC), the calculation amount of DPM is much less. Therefore, it makes the proposed protocol much more efficient while enhancing the security. The PKC is adopted to protect the transmitted messages between MME and Home Subscriber Server (HSS). The evaluation demonstrates that the proposed protocol is more secure and relatively more efficient than other PKC based security enhanced EPS AKA protocols, and satisfies all the security requirements including confidentiality, authentication, integrity and network availability.