Li-Fung Chang

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The Mobile IP (MIP) protocol for IP version 4 provides continuous Internet connectivity to mobile hosts. However, currently it has some drawbacks in the areas of survivability, performance, interoperability with protocols for providing QoS. We have proposed an alternative protocol, Mobile IP with Location Registers (MIP-LR), which overcomes some of these(More)
{ This paper evaluates the use of packet scheduling to provide multiple service classes for bursty data traac. In particular, we study the performance of the weighted fair queueing algorithm by simulating various scenarios in a packet cellular wireless network similar to an EDGE system. The results show that, due to the burstiness of data traac, traditional(More)
— Current cellular subscribers have a geographic phone number (e.g., in AMPS and U.S. digital cellular systems) or a number which contains the network provider's identity (e.g., in GSM), and whenever subscribers register or receive (and possibly, originate) a call, a home location register (HLR) database has to be queried. The wired infrastructure supports(More)
Performance enhancing proxies have drawn considerable interests from the network community a s a n eeective approach to improve user experience in cellular networks. However, previous research has been focusing on the design of proxy servers as well as the functions that these servers provide. In this paper, we study the placement of proxy servers,(More)