Universal Multiparty Data Exchange and Secret Key Agreement

Multiparty Secret Key Exchange Using a Random Deal of Cards

We consider the problem of multiparty secret key exchange. A \team" of players P1 through Pk wishes to determine an n-bit secret key in the presence of a compu-tationally unlimited eavesdropper, Eve. The team players are dealt hands of cards of prespeciied sizes from a deck of d distinct cards; any remaining cards are dealt to Eve. We explore how the team can use the information contained in th...

A Bound for Multiparty Secret Key Agreement and Implications for a Problem of Secure Computing

We consider secret key agreement by multiple parties observing correlated data and communicating interactively over an insecure communication channel. Our main contribution is a single-shot upper bound on the length of the secret keys that can be generated, without making any assumptions on the distribution of the underlying data. Heuristically, we bound the secret key length in terms of “how f...

Information-Theoretic Secret Key Agreement

Studies on Verifiable Secret Sharing, Byzantine Agreement and Multiparty Computation

This dissertation deals with three most important as well as fundamental problems in secure distributed computing, namely Verifiable Secret Sharing (VSS), Byzantine Agreement (BA) and Multiparty Computation (MPC). VSS is a two phase protocol (Sharing and Reconstruction) carried out among n parties in the presence of a centralized adversary who can corrupt up to t parties. Informally, the goal o...

Multiparty Key Agreement Using Bilinear Map

⎯ A key agreement protocol is a cryptographical primitive which allows participants to share a common secret key via insecure channel. In particular, a multiparty key agreement protocol is a key agreement protocol that can manage arbitrary number of participants at once. In the security point of view, authentication and forward secrecy are the most important requirements in such protocols. One ...