Access Service Network (ASN) Gateway Relocation Algorithms in WiMAX Networks

WiMAX forum is developing and standardizing the end-to-end network architecture. The access service network (ASN) gateway (GW) plays a critical role in the system. How to reduce the load in the ASN GW has become an important issue. However, the standards only define the ASN GW relocation procedure without specifying when the relocation should be performed. In a real development, the key challenge to reduce the load of an ASN GW heavily relies on the decision of an appropriate time to relocate the MSs in an ASN GW. In this paper, we propose two effective ASN GW relocation algorithms. They can accurately estimate the traffic load and decide when to perform ASN GW relocation. The proposed algorithms can be accomplished by ASN GW alone. There is no need to exchange information among ASN GWs or get any help from other servers. They are fully compatible with existing systems and should be easy to implement. Extensive simulations have been performed to investigate the performance of the proposed algorithms. The results show that the proposed algorithms can increase overall throughput and reduce the loads of ASN GWs.