We consider the problem of achieving reliable/secure transmission of a message in an insecure network such as the Internet. The sender S and the receiver R are two nodes of a synchronous network and the insecurity is modeled by a centralized adversary who can disrupt the network in a variety of ways. We assume that the adversary has infinite computational power. We discuss various abstract models available in the literature for this problem and present a unified taxonomy for these models. We present a necessary and sufficient condition for the existence of a protocol and discuss the protocols of Dolev and Abu-Amara. Then, we will take a closer look at a powerful technique called Matching Technique and obtain optimal protocols for these problems.
Professor Pandu Rangan obtained his PhD from the Indian Institute of Science (Bangalore, India). Since 1982, he serves as a faculty member in the department of Computer Science and Engineering of the Indian Institute of Technology (Madras). He joined the rank of professors in 1995 and served as Head of Department from 1998 to 2001. He was recently honored as Fellow of the Indian National Academy of Engineering (INAE). He served as a member of the board of Directors of the International Association for Cryptologic Research (IACR) from 2002 to 2005. He is currently in the editorial board of LNCS published by Springer-Verlag and in the editorial board of the Journal of Parallel and Distributed Computing. He served as PC chair/General chair for a number of leading conferences such as ASIACRYPT and INDOCRYPT. He has published extensively in various reputed international journals and conferences covering a vast range of topics in algorithms and cryptology. In algorithms, his research focus is in graph algorithms, randomized algorithms and parallel algorithms. In cryptology, he is focusing in secure/reliable message transmission which is a key problem to solve multiparty computations.