Secret key sharing and secret key generation

Mariam E. Haroutunian, Narek S. Pahlevanyan

We investigate the biometric generated secret key sharing system. We consider the generalization of the secret key rate, studied by Ignatenko and Willems [1]: the notion of E-achievable secret key rate is introduced. The lower and upper bounds for the largest E-achievable secret key rate are obtained.

孝也 栃窪

Amos Beimel

Imre Csiszár, Prakash Narayan

Shannon theoretic shared secret key generation by multiple terminals is considered for a source model in which the components of a discrete memoryless multiple source and a noiseless public channel of unlimited capacity are available for accomplishing this goal. A shared secret key is generated for distinct coalitions of terminals, with all the terminals cooperating in this task through their public communication. A communication from a terminal can be a function of its observed source component and of all previous communication. Member terminals of a coalition unite in recovering the key. Secrecy is required from an eavesdropper that observes the public interterminal communication. A single-letter characterization of the shared secret key capacity is obtained. When the key must be concealed additionally from subsets of coalition members, we provide an upper bound for the strict shared secret key capacity.

Sirin Nitinawarat, Chunxuan Ye, Alexander Barg +2 more

We consider secret key generation for a "pairwise independent network" model in which every pair of terminals observes correlated sources that are independent of sources observed by all other pairs of terminals. The terminals are then allowed to communicate publicly with all such communication being observed by all the terminals. The objective is to generate a secret key shared by a given subset of terminals at the largest rate possible, with the cooperation of any remaining terminals. Secrecy is required from an eavesdropper that has access to the public interterminal communication. A (single-letter) formula for secret key capacity brings out a natural connection between the problem of secret key generation and a combinatorial problem of maximal packing of Steiner trees in an associated multigraph. An explicit algorithm is proposed for secret key generation based on a maximal packing of Steiner trees in a multigraph; the corresponding maximum rate of Steiner tree packing is thus a lower bound for the secret key capacity. When only two of the terminals or when all the terminals seek to share a secret key, the mentioned algorithm achieves secret key capacity in which case the bound is tight.

Himanshu Tyagi, Shun Watanabe