John S. Baras received a B.S. in Electrical Engineering from the National Technical University of Athens, Greece, in 1970, M.S. and Ph.D. in Applied Mathematics from Harvard Univ. in 1971 and 1973. Founding Director of the Institute for Systems Research from 1985 to 1991. Since August 1973 he has been with the Electrical and Computer Engineering Department, and the Applied Mathematics Faculty, at the University of Maryland, College Park. Since 1991 Dr. Baras has been the Director of the Maryland Center for Hybrid Networks (HYNET). His many awards include the 1980 George S. Axelby Prize of the IEEE Control Systems Society and the 2007 IEEE Communications Society Leonard G. Abraham Prize in the Field of Communication Systems.Fellow of the IEEE and a Foreign Member of the Royal Swedish Academy of Engineering Sciences (IVA). He has given many invited plenary lectures at prestigious international conferences including the IEEE CDC, ECC, ECAI, Mobicom. His research interests include control, communication and computing systems.George Theodorakopoulos is a senior researcher at the Ecole Polytechnique Federale de Lausanne (EPFL), Lausanne, Switzerland. He received his Ph.D. and M.Sc. from the University of Maryland, College Park, and his B.Sc. from the National Technical University of Athens, Greece, all in Electrical and Computer Engineering, in 2007, 2004, and 2002, respectively. Half of his Ph.D. work was on the application of the algebraic path problem to trust computation. This work resulted in two awards: the best paper award at the ACM Wireless Security workshop (WiSe 2004) and the IEEE Leonard G. Abraham prize (IEEE Journal on Selected Areas in Communications 2006). His research interests also include game theory (the other half of his Ph.D.), trust and reputation systems, and network security.

• Classical Shortest Path.- The Algebraic Path Problem.- Properties and Computation of Solutions.- Applications.- Related Areas.- List of Semirings and Applications.

John S. Baras received a B.S. in Electrical Engineering from the National Technical University of Athens, Greece, in 1970, M.S. and Ph.D. in Applied Mathematics from Harvard Univ. in 1971 and 1973. Founding Director of the Institute for Systems Research from 1985 to 1991. Since August 1973 he has been with the Electrical and Computer Engineering Department, and the Applied Mathematics Faculty, at the University of Maryland, College Park. Since 1991 Dr. Baras has been the Director of the Maryland Center for Hybrid Networks (HYNET). His many awards include the 1980 George S. Axelby Prize of the IEEE Control Systems Society and the 2007 IEEE Communications Society Leonard G. Abraham Prize in the Field of Communication Systems.Fellow of the IEEE and a Foreign Member of the Royal Swedish Academy of Engineering Sciences (IVA). He has given many invited plenary lectures at prestigious international conferences including the IEEE CDC, ECC, ECAI, Mobicom. His research interests include control, communication and computing systems.George Theodorakopoulos is a senior researcher at the Ecole Polytechnique Federale de Lausanne (EPFL), Lausanne, Switzerland. He received his Ph.D. and M.Sc. from the University of Maryland, College Park, and his B.Sc. from the National Technical University of Athens, Greece, all in Electrical and Computer Engineering, in 2007, 2004, and 2002, respectively. Half of his Ph.D. work was on the application of the algebraic path problem to trust computation. This work resulted in two awards: the best paper award at the ACM Wireless Security workshop (WiSe 2004) and the IEEE Leonard G. Abraham prize (IEEE Journal on Selected Areas in Communications 2006). His research interests also include game theory (the other half of his Ph.D.), trust and reputation systems, and network security.

• Classical Shortest Path.- The Algebraic Path Problem.- Properties and Computation of Solutions.- Applications.- Related Areas.- List of Semirings and Applications.

John S. Baras received a B.S. in Electrical Engineering from the National Technical University of Athens, Greece, in 1970, M.S. and Ph.D. in Applied Mathematics from Harvard Univ. in 1971 and 1973. Founding Director of the Institute for Systems Research from 1985 to 1991. Since August 1973 he has been with the Electrical and Computer Engineering Department, and the Applied Mathematics Faculty, at the University of Maryland, College Park. Since 1991 Dr. Baras has been the Director of the Maryland Center for Hybrid Networks (HYNET). His many awards include the 1980 George S. Axelby Prize of the IEEE Control Systems Society and the 2007 IEEE Communications Society Leonard G. Abraham Prize in the Field of Communication Systems.Fellow of the IEEE and a Foreign Member of the Royal Swedish Academy of Engineering Sciences (IVA). He has given many invited plenary lectures at prestigious international conferences including the IEEE CDC, ECC, ECAI, Mobicom. His research interests include control, communication and computing systems.George Theodorakopoulos is a senior researcher at the Ecole Polytechnique Federale de Lausanne (EPFL), Lausanne, Switzerland. He received his Ph.D. and M.Sc. from the University of Maryland, College Park, and his B.Sc. from the National Technical University of Athens, Greece, all in Electrical and Computer Engineering, in 2007, 2004, and 2002, respectively. Half of his Ph.D. work was on the application of the algebraic path problem to trust computation. This work resulted in two awards: the best paper award at the ACM Wireless Security workshop (WiSe 2004) and the IEEE Leonard G. Abraham prize (IEEE Journal on Selected Areas in Communications 2006). His research interests also include game theory (the other half of his Ph.D.), trust and reputation systems, and network security.

• Classical Shortest Path.- The Algebraic Path Problem.- Properties and Computation of Solutions.- Applications.- Related Areas.- List of Semirings and Applications.