Abstract
The IEEE 802.16 is expected to become one of the most important standards for broadband wireless access in the future. In addition, WiMAX Network Working Group (NWG) pro-poses an end-to-end system architecture which uses 802.16 as the radio link. In WiMAX, Mobile IP is used for mobility management. However, the WiMAX Access Service Network (ASN) gateway will overload when it anchors too many mobile nodes. The gateway relocation procedure defined in the standards can help reduce the load by removing some anchored mobile nodes to other ASN gateway. In this thesis, we study when to perform the relocation to reduce ASN gateway’s load. We use random early detection(RED) queue management and relocation algorithms to trigger relocation. The mechanisms we propose can make ASN gateway to perform relocation at appropriate time and prevent some critical problems. Be-sides, we perform relocation earlier with the prediction mechanism we proposed and let users get good communication quality earlier.