A vertical handoff decision process and algorithm based on context information in CDMA-WLAN interworking

The integration of WLANs and CDMA networks has recently evolved into a very hot issue. In order to support a vertical handoff, we propose a context based vertical handoff decision process and the corresponding algorithms from WLAN to CDMA system, and vice versa, based on wireless channel assignment. We focuses on the handoff decision which uses context information such as dropping probability, blocking probability, GoS (Grade of Service), the number of handoff attempts and velocity. As a decision criterion, velocity threshold is determined to optimize the system performance. The optimal velocity threshold is adjusted to assign available channels to the mobile stations with various handoff strategies. The proposed scheme is validated using computer simulation. Also, the overflow traffic (a vertical handoff) is evaluated and compared with non-overflow traffics in terms of GoS.