The papers in this book were prepared for and presented at the International ConferenceonInformationNetworking2004(ICOIN2004),whichwasheldfrom February 18 to 20, 2004 at Busan, Korea.It was organizedby the KISS (Korean Information Science Society) SIG-IN in Korea and the IPSJ (Information P- cessing Society of Japan) SIG-IN. The papers were selected through two steps: (1)referralbyTPCmembersand reviewers;and(2)on-sitepresentationreviews by session chairs and conference participants. The theme of ICOIN 2004 was Convergencein Broadband and Mobile N- working , considering high-speed mobile networks. Even though it seems that a kind of slow-speed mobile Internet service is to be provided in the market sooner or later, it would not be an ultimate solution for the users, who require more QoS-rich services. In the near future, mobile services will adopt hi- speed networking technology. At the same time, mobile service users will anti- pate that a reasonable level of quality of service and security is provided. Based onthis,ICOIN2004requestedpapersontechnologiesformobility,qualityofs- vice,security,broadbandaccess,andapplications,focusingonenhancedInternet protocolsandalgorithms,their implementation, and the convergencetechnology required to support wired and wireless Internet. This book contains articles on the following subjects related to information networking from the low-layer transmission technologies to the higher-layer p- tocols and services. Mobility Internet and Ubiquitous Computing: Concerned with mobile ad hoc networking, mechanisms for ubiquitous environments, routing in mobile networks, and mobile IP protocols. QoS, Measurement and Performance Analysis: Concerned with QoS-related routingalgorithmsand protocols,QoS provisioningInternet protocols,m- elling and analysis, and performance measurement. High-Speed Network Technologies: Concerned with multicast in high-speed networks, advanced algorithms and protocols, and switching and routing.