Abstract
Handoff provides seamless mobility to users. When a user crosses the cell boundary of one base station
(BS) and enters into the control area of another base station while a call is in progress, this process is called handoff.
Horizontal Handoff (HHO) occur if the two base stations use the same network technology while vertical handover
occur if the Serving Network (SN) and the Target Network (TN) uses different network technologies. One of the major
technical challenges of vertical handover (VHO) is the transferring of security context. In heterogeneous networks the
security mechanism of one network is different from other network. Therefore, when a mobile terminal (MT) executes
vertical handover, security context with serving network is usually terminated and a new context with target network
is created for the mobile terminal. If we securely transfer the old security context in VHO and reuse it with necessary
adaptations, then overall latency in VHO will be reduced. In this way a full security context creation is avoided in
VHO process and latency is reduced because home network is not involved in the handover process to transfer the
security context. This paper presents an algorithm that provide optimized security context switching with low latency
in vertical handover process.
