Non-Interactive Hierarchical Key Distribution for MANETs
IBM T.J. Watson Research Center
Key agreement is a fundamental security functionality by which pairs of nodes agree
on shared keys to be used for protecting their pairwise communications. In this work
we study key-agreement schemes that are well-suited for the mobile network environment.
Specifically, we describe schemes with the following characteristics:
Non-interactive: any two nodes can compute a unique shared secret key without interaction;
Identity-based: to compute the shared secret key, each node only needs its own secret key
and the identity of its peer;
Hierarchical: the scheme is decentralized through a hierarchy where intermediate nodes
in the hierarchy can derive the secret keys for each of its children without any limitations or
prior knowledge on the number of such children or their identities;
Resilient: the scheme is fully resilient against compromise of any number of leaves}
in the hierarchy, and of a threshold number of nodes in each of the upper levels of the hierarchy.
Several schemes in the literature have three of these four properties, but the schemes in this
work are the first to possess all four. This makes them well-suited for environments such as
MANETs and tactical networks which are very dynamic, have significant bandwidth and energy
constraints, and where many nodes are vulnerable to compromise. We provide rigorous analysis
of the proposed schemes and discuss implementations aspects.
Tal Rabin is a research staff member in, and manager of the Cryptography
Research group at IBM T.J. Watson Research Center. Tal received her
Ph.D. in Computer Science from the Hebrew University, Israel in 1994,
and was an NSF Postdoc Fellow at MIT between 1994-1996. Following her
postdoc she joined IBM in 1996, and started managing the group in 1997.
Tal's areas of interest are secure distributed protocols, provable security
of cryptographic tools and privacy. Dr. Rabin publishes regularly in the
leading cryptography and security conferences and journals. She will
serve as the Program chair of Crypto 2010.