Telecommunications and Networking ICT 2004 : 11th International Conference on Telecommunications Fortaleza Brazil August 1 6 2004. Proceedings This book constitutes the refereed proceedings of the 11th International Conference on Telecommunications ICT 2004 held in Fortaleza Brazil in August 2004. The 188 revised full papers presented were carefully reviewed and selected from 430 submissions. The papers are organized in topical sections on multimedia services antennas transmission technologies and wireless networks communication theory telecommunication pricing and billing network performance and telecommunication services active network and mobile agents optical photonic techniques optical networks ad hoc networks signal processing network performance and MPLS traffic engineering SIP Qos and switches network operation management mobility and broadband wireless cellular system evolution personal communication satellites mobility management network reliability ATM and Web services security switching and routing next generation systems wireless access Internet etc