This book contains the best papers of the Third International Conference on E-business and Telecommunications (ICETE), which was held in 2006 in Portugal. This conference reflects a continuing effort to increase the dissemination of recent research results among professionals who work in the e-business field. ICETE is a joint international conference integrating four major areas of knowledge that are divided into four cor- sponding conferences: ICE-B (Int’l Conf. on e-Business), SECRYPT (Int’l Conf. on Security and Cryptography), WINSYS (Int’l Conf. on Wireless Information Systems) and SIGMAP (Int’l Conf. on Signal Processing and Multimedia). The program of this joint conference included seven outstanding keynote lectures presented by internationally renowned distinguished researchers who are experts in the various ICETE areas. Their keynote speeches contributed to heightening the ov- all quality of the program and significance of the theme of the conference. The conference topic areas define a broad spectrum in the key areas of e-Business and telecommunications. This wide view has made it appealing to a global audience of engineers, scientists, business practitioners and policy experts. The papers – cepted and presented at the conference demonstrated a number of new and innovative solutions for e-business and telecommunication networks, showing that the technical problems in both fields are challenging, related and significant.