This book constitutes the thoroughly refereed post-conference proceedings of the 7th International Joint Conference on e-Business and Telecommunications, ICETE 2010, held in Athens, Greece, in July 2010. The 28 revised full papers presented together with 1 invited paper in this volume were carefully reviewed and selected from 422 initial submissions. They have passed two rounds of selection and improvement. According to the topics of the particular conference the papers are organized in thematical parts on data communication networking (DCNET), e-business (ICE-B), optical communication systems (OPTICS), security and cryptography (SECRYPT), signal processing and multimedia applications (SIGMAP), wireless information networks and systems (WINSYS).