4 research outputs found
Distributed Storage for Data Security
We study the secrecy of a distributed storage system for passwords. The
encoder, Alice, observes a length-n password and describes it using two hints,
which she then stores in different locations. The legitimate receiver, Bob,
observes both hints. The eavesdropper, Eve, sees only one of the hints; Alice
cannot control which. We characterize the largest normalized (by n) exponent
that we can guarantee for the number of guesses it takes Eve to guess the
password subject to the constraint that either the number of guesses it takes
Bob to guess the password or the size of the list that Bob must form to
guarantee that it contain the password approach 1 as n tends to infinity.Comment: 5 pages, submitted to ITW 201
Distributed Task Encoding
The rate region of the task-encoding problem for two correlated sources is
characterized using a novel parametric family of dependence measures. The
converse uses a new expression for the -th moment of the list size, which
is derived using the relative -entropy.Comment: 5 pages; accepted at ISIT 201
Distributed Storage for Data Security
Abstract-We study the secrecy of a distributed storage system for passwords. The encoder, Alice, observes a length-n password and describes it using two hints, which she then stores in different locations. The legitimate receiver, Bob, observes both hints. In one scenario we require that the number of guesses it takes Bob to guess the password approach 1 as n tends to infinity and in the other that the size of the list that Bob must form to guarantee that it contain the password approach 1. The eavesdropper, Eve, sees only one of the hints; Alice cannot control which. For each scenario we characterize the largest normalized (by n) exponent that we can guarantee for the number of guesses it takes Eve to guess the password