International Academy Publishing (IAP)
In IEEE 802.16e standard, mobility and handover are added as basic capabilities. It defines a framework providing specific methods or algorithm for handover that can be deployed in mobile stations to enable them for switching seamlessly from one base station to another. A Mobile Subscriber Station (MSS) basically conducts hard handover operation when it moves to another Base Station (BS). Therefore, the MSS is not able to send or receive the data during handover process and these data should be delayed. As a result, real time packet could be dropped by handover delay.