Handover mechanisms in next generation heterogeneous wireless ...

INTRODUCTION
network trust pattern of its nearby networks using mobile users’ handover records
without relying on direct links with its neighbours. In this scheme, a mobile user can
obtain necessary network trust information dynamically from its serving access network,
and thus has sufficient flexibility to work with a large number of network operators.
In Chapter 5, a network trust information assisted handover algorithm is presented for
handover in a multi-operator environment. On a cost basis, the proposed algorithm uses
network trust relationship in additional to other handover metrics such as signal strength,
delay, network load and so forth. This provides a mobile user with an intelligent
approach of dealing with complex trust relationships between network operators.
According to the proposed algorithm, network trust information that is needed in a
handover can be considered as an integral part of handover decision algorithm rather
than as a separated add-on. This effectively avoids unnecessary handover attempts, and
ensures reliable handover in a multi-operator environment. The algorithm can work
without compromising Quality of Service (QoS).
Chapter 6 introduces a proxy-based authentication localisation scheme for handover
between networks without a trust relation. The proposed scheme presents a method of
relaying a mobile’s home network’s authentication authority to a third party proxy
based on a proposed trust association model. To provide secure and controllable
authentication localisation, a set of fast authentication related algorithms are presented.
The proposed trust association model along with the fast authentication algorithms
enable the authentication required in a handover to be locally processed. This avoids
resorting to the home AAA server for identity verification in a handover. The proposed
scheme is particularly effective for the handover taking place between two networks
without a trust relation, and can result in great performance improvement.
In Chapter 7, a generic multi-interface mobile terminal model is described. The
proposed model provides a multi-interface architecture that supports multiple
heterogeneous network interfaces being alternatively used and media independent
handover. Its design focus is to enable the multi-interface function and support ordinary
upper layer protocols such as TCP/IP and Mobile IPv4 at the mobile end without
modifying wireless network infrastructure already in use. This makes sure that the
proposed model that is compatible with the latest IEEE 802.21 standard can be
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