On Mobility Solutions in Heterogeneous Networking Environments

Abstract: Mobility support for users and devices, such as sensors, connecting to the Internet is a continuously growing trend. Different types of wireless networking technologies like WiFi, LTE, and ZigBee are available, creating a heterogeneous wireless networking environment. In general, the technology, ranging from network equipment to communications protocols, available today, tends to be designed with limited exibility when it comes to supporting heterogeneity. Proprietary technology and highly optimized mechanisms limit the potential use of networking infrastructure for multiple purposes. Supporting mobility for wireless devices between different networking technologies and administrative domains requires secure and scalable mobility management solutions. Current research in the field of mobility management and security in heterogeneous networking environment tends to handle mobility management performance, such as communications characteristics, and security related aspects as separate, and more or less mutuallyexclusive. The work presented in this thesis serves to challenge this trade-off and proposes solutions that seeks to brigde the gap between the two areas. This thesis proposes using an Authentication, Authorization and Accounting (AAA) system based on the RADIUS AAA protocol that enables a common AAA infrastructure to operate in a heterogeneous networking environment, and that enables a hierarchical interconnection structure between service providers. The proposed AAA architecture offers a highly scalable AAA infrastructure with access technology independent support for user and device authentication as well as mobility on a global scale. Further, to support handoffs between networks, a set of methods for facilitating improved handoff decisions for intra- and inter-operator mobility in heterogeneous networks are presented. These methods rely on metrics that include indicators on network load conditions to improve service stability and decrease application down time during handoff. Results show that the proposed AAA infrastructure can be built to scale in order to support a very large number of entities, more than 1000 user or device authentications per second, using industry standard hardware. Further, an AAA architecture compatible sensor authentication protocol is proposed, implemented, and validated that supports sensor mobility and reduces power consumption, on wireless sensor nodes, with 33% compared to state-of-the-art protocols by reducing CPU and communications overhead. Using the proposed mechanism for facilitating handos in wireless sensor networks, a reduction of 44% in packet loss is achived during a mobility session compared to a traditional solution.