OmniCon: a Mobile IP-based vertical handoff system for wireless LAN and GPRS links

摘要: Wi-Fi based hotspots offer mobile users broadband wireless Internet connectivity in public work spaces and corporatesuniversity campuses. Despite the aggressive deployment of these recent years, high-speed access remains restricted to small geographical areas due limited physical coverage LANs. On other hand, despite their lower throughput, cellular networks have a significantly wider are thus much more available. Recognizing that 2.5G or 3G can effectively complement LANs, we set out develop vertical handoff system allows seamlessly fall back such as general packet radio service (GPRS) whenever LAN is not The resulting mechanism network connection node operate over multiple way transparent end user applications. In this paper, present design, implementation, evaluation fully operational system, called OmniCon, which enables nodes automatically switch between GPRS, on availability, by introducing simple extension existing Mobile IP implementation. We discuss design issues proposed for heterogeneous networks, including setup problems address translation, disparity link characteristics LANs GPRS. A detailed performance study OmniCon prototype demonstrates its ability migrate active connections two technologies with low latency close zero loss. Copyright © 2006 John Wiley & Sons, Ltd.