A Vertical Soft Handoff Scheme Based on SIP in the Ubiquitous Wireless Network

摘要

Ubiquitous Wireless Network will be the important infrastructure for ubiquitous information service in the future. Ubiquitous Wireless Network is objectively heterogeneous network, so vertical handoff is one of crucial topics. A vertical soft handoff scheme is proposed based on SIP using Wireless Access Gateway (RGW). RGW triggers and controls the handoff session to ensure same two-way delay of handoff and rate of zero-loss packet for real-time streaming media. Using M/M/1 queue model, delay of the scheme meets requirement of real-time streaming media.