移动多媒体网络中的无缝切换

SEAMLESS HANDOVER IN MOBILE MULTIMEDIA NETWORKS

第三代移动通信（３Ｇ）面临的一个重 要的挑战就是要无缝集成固定和移动 网络中的多媒体业务。对于移动用户 来讲，网络支持的业务有图像、多媒 体、数据以及不同服务级别的话音业 务。为了满足以上业务需求，３Ｇ系统 必须具有丰富的性能。如今普遍采用 ＡＴＭ技术的同质网络虽然支持很多用 户，但此种网络结构不可能成为最终 的解决方案（至少从学术界、网络设备 制造商的观点来看）。而以太网家族中 高速设备的快速发展，已经部分代替 了ＡＴＭ。同时基于因特网业务的爆炸性 增长，已经确保ＩＰ仍将成为下一代系 统网络层协议。本文讨论了ＩＰ网因支 持移动业务而产生的问题，以及对切 换技术进行的分析。

One of the major objective of third- generation mobile communications(3G) is the seamless integration of advanced multimedia services. Such systems will support audio , video , multimedia , data and speech services in a variety of levels . To achieve this, 3G system must provide adequate performance for each user . the universal adoption of ATM seems unlikely to become a reality . ATM has been preempted by the very rapid development of ultra high speed Ethernet .And the explosive growth of Internet applications has ensured that IP will remain the network layer protocol of next generation systems . This article discusses the problem for supporting mobility in IP, and also provides some solutions for handover in IP.