e need to tunnel packets, instead we add a routing header to each packet. The ME also has more control to decide when to optimize routes, since it creates the opti- mized route rather than the HA; thus resulting in simpler MIPv6 HA. When migrating from MIPv4 to MIPv6, we need to make changes to CHs to employ route optimization. In contrast, all IPv6 CHs will support route optimization automatically. CONCLUSIONS In this chapter we have provided an overview of the ROO (R4 and R5) architecture. We have also described its main functional elements and its key interfaces. In addition, we cover the essential items of the mobility management, application level registration, location services, multimedia, QoS, Transport issues, etc. References Drafting Team. Vision and Road Map for UMTS Evolution, TSGS#8(00)0337, 2000. 3GPP, Study on Release 2000 SERVICES and Capabilities (3G TS 22.976), V2.0.0, 2000- TS 22.003. 3rd Generation Partnership Project, Technical Specification Group Services and System Aspects, Circuit Tele-services Supported by a Public Land Mobile Network (PLMN). TS 22.002. 3rd Generation Partnership Project, Technical Specification Group Services and System Aspects, Circuit Bearer Services (BS) Supported by a Public Land Mobile Network (PLMN). TS 22.004. 3rd Generation Partnership Project, Technical Specification Group Services and System Aspects, General on Supplementary Services. S 22.060. General Packet Radio Service (GPRS) Stage 1. 3GPP, Architecture Principles for Release 2000 (3G TR 23.821), V1.0.1, 2000-07). 3GPP, Combined GSM and Mobile IP Mobility Handling in UMTS IP CN 3G TR 23.923 version 3.0.0, 2000-05. IETF RFC 2002 (1996): IP Mobility Support, C. Perkins. [10] Internet draft, Johson and Perkins, Mobility Support in IPv6, October 1999. http://www.ietf.org/internet-drafts/draft-ietf-mobileip-ipv6-09.txt PRENTICE FIFTH EDITION A Completely Revised Bestseller with an Updated Industry Overview and New Coverage of Mobile Networks. LTE, Spectrum, Cloud Computing. and More! THE ESSENTIAL GUIDE TO Telec