Improved internet protocol multimedia subsystem authentication for long term evolution

Long Term Evolution (LTE) is a major technology to be used in the 4th generation (4G) mobile network and the core network is evolving towards a converged packet based framework for all services. As a part of the evolved core network, Internet Protocol (IP) Multimedia Subsystem (IMS) provides multimedia services (data, voice, video and variations) over packet switched networks. LTE and IMS are both defined by the 3rd Generation Partnership Project (3GPP) group, and the specification identifies that a LTE user device has to carry out two authentication steps to access IP multimedia services. The first authentication step is used to gain LTE network admission and the second authentication step is the IMS authentication used to gain access to the multimedia services. It is observed that the 4G standardized authentication protocols include double execution of the Authentication and Key Agreement (AKA) which increases the system’s complexity, results in significant authentication delay and high terminal energy consumption. Authentication is very important for a terminal to gain access to a network and therefore considerable previous research into this topic has occurred. However a common limitation of previously proposed authentication systems is either a lack of security or significant system modification. This research proposes the Improved AKA (IAKA) authentication protocol which binds the two layer’s authentication procedures by using the unified IP Multimedia Private-user Identity (IMPI). The proposed IAKA only executes the AKA protocol once in the network layer and generates authentication credentials which would be used in the second IMS service layer authentication. This research work included providing IAKA authentication protocol, developing a LTE IMS integrated network by using OPNET Modeller, simulation of the IAKA and the legacy 3GPP defined 4G LTE AKA authentication protocol under different environments, and in-depth analysis of the system performance, security and terminal’s energy consumption. It is shown that the proposed IAKA carries out terminal authentication correctly, improves security, reduces IMS layer authentication delay by up to 38%, and provides an 81.82% terminal energy consumption saving

Improved One-Pass IP Multimedia Subsystem Authentication for UMTS

As defined in the 3rd Generation Partnership Project specifications, a Universal Mobile Telecommunications System (UMTS) user device has to carry out two authentication steps to access multimedia services in IP Multimedia Subsystem (IMS). The first authentication step is used to gain UMTS General Packet Radio Service (GPRS) network admission. The second authentication step is the IMS authentication. The authentication steps utilize Authentication and Key Agreement (AKA) and many of the authentication steps are similar. This paper proposed a simplified authentication process known as Improved AKA (I-AKA) which reduced the two authentication steps used to access the UMTS GPRS network and IMS services to one authentication step. Simulation results showed the I-AKA protocol could significantly reduce the authentication delay and improve overall efficiency