  As wireless access technologies grow rapidly, the recent studies have focused
on granting mobile users the ability of roaming across different wireless
networks in a seamless manner thus offering seamless mobility. The different
characteristics of each wireless technology with regards to QoS brought many
challenges for provisioning the continuous services (audio/video streaming) in
a seamless way. In this paper, we intend to review the existing context-aware
methods which offered solutions for service continuity. We looked at the types
of context information used in each solution. Through this study, it is clear
that context awareness plays a significant role in handover process in order to
satisfy users demanding seamless services. Therefore, the goal of this paper is
to compare the existing methods grouped as general, IMS based, and WLAN/WiMAX
solutions in terms of several criteria, such as interworking architecture,
service continuity, and QoS provisioning.
