An Extensible Overlay Infrastructure for Wide-Area Stream Processing and Dissemination

nomics and Business, Athens, Greece. She worked as a software engineer for the Athens Stock Exchange untill 2002. She then joined the graduate program in Brown University, where she received her Sc. Acknowledgments The first person I would like to thank is my advisor, Ugur Cetintemel. Ugur's positive attitude inspired me from the first time I met him, in my visit at Brown as a perspective student. During my studies in Brown, he continued to be an endless source of motivation and encouragement for me. Ugur taught me how to be a researcher, invested a lot of time teaching me how to effectively present my ideas and provided his valuable advice on many critical points in my career and personal life. I will always be grateful to him for his guidance, his support and his patience all of these years. I would like also to thank my committee member and co-author, John Jannotti. His interesting questions and feedback helped me understand my own work in more depth and had an important impact on this dissertation. Thanks are also due to my third committee member, Stan Zdonik, whose support and encouragement helped me pursue my career goals. I would also like to thank the student members of the Data Management Group in Brown. I am really happy I met and worked with all of you! Nesime, you have inspired me in many different ways, in my research, in my career choices (and even during our gym classes!). My dear officemates, Ying and Jeong-Hyon, thank you for sharing with me many stressful moments. Yanif, I really appreciate the effort and time you spent discussing the details of XPORT and building our demonstration. Finally, I would like to thank the summer interns who contributed to the prototyping of my work: The years I spent at Brown were the best years of my life thanks to my friends. Manos Renieris, Yiannis Tsochantaridis and Aris Anagnostopoulos patiently listened and advised me, especially in the early years. Ioanna Papaefthimiou and Ioanna Grypari were always bringing out the positive aspect of any situation and they made my life so much more fun. I would like also to thank Cleopatra Stefan Roth and Yiannis Vergados for all the laughs we shared. Finally, the last couple of years were much more enjoyable and less lonely than I ever expected thanks to Menia Pavlakou, Sofocles Mavroeidis, Babis Papamanthou and Dimitra …