摘要： 802.11网络现有的切换方案可以解决域内切换问题，域间切换涉及网络层切换操作，导致较大的网络延迟和大量的分组丢失。该文提出一种基于虚拟接口的802.11网络切换方法，通过对一个物理接口设备分时使用，使得无线终端在保证现有通信质量的情况下，平滑地完成与新无线访问点AP建立无线链路的过程。该方法具有实现简单、不用修改现有的Mobile IP协议等优点，在NS系统上的模拟表明，该方法能够满足实时交互式应用对移动切换过程中的网络质量需求。

关键词: 802.11网络, 移动IP, 平滑切换, 虚拟设备

Abstract:

Existing schemes in IEEE 802.11 network can only resolve the problems of inner ESS domain, but cannot effectively resolve that of inter ESS domains because the handoff between two ESS domains involve network layer operations. This paper proposes a smooth handoff scheme based on virtual interface in wireless network. This scheme applies a time-sharing policy on physical wireless interface, which enables mobile station to establish new wireless link with the right new access point and to keep normal communication in present wireless link with the previous access point at the same time, so it can perfectly resolve the problems of packet latency and loss ratio for both inner ESS domain handoff and inter ESS domain handoff. Simulation results on NS2 confirmes that it can satisfy the demand of interactive real-time applications in wireless mobile networ

Key words: 802.11 network, mobile IP, smooth handoff, virtual device

中图分类号: 

• TP393