Randomness, Everlasting Security, and Undetectability

Speaker : Don Towsely
UMASS Amherst
Date: 25/06/2014
Time: 3:00 pm - 4:00 pm
Location: LINCS Meeting Room 40


Security and privacy are fundamental concerns in today‘s world. These concerns have become particularly prominent with Snowden’s revelationsof the presence of the NSA in our daily lives. These revelations have shown that traditional cryptographic techniques do not provide as was expected. This has called into question how security and privacy can be provided. In this talk we investigate how randomness in the environment can be used to provide everlasting security and undetectability(privacy) in wireless communications. In the first part of the talk we describe a practical way to harness this randomness to provide and improve the security of wireless communications. We introduce the notion of “dynamic secrets”, information shared by two parties, Alice and Bob, engaged in communication and not available to an adversary, Eve. The basic idea is to dynamically generate a series of secrets from randomness present in the in wireless environment. These dynamic secrets exhibit interesting security properties and offer a robust alternative to cryptographic security protocols. We present a simple algorithm for generating these secrets and using them to ensure secrecy.In some situations, Alice and Bob may want not only to secure their communications but to keep it private. In the second part of our talk we focus on the use of randomness to conceal the communications. Here the challenge is for Alice to communicate with Bob without an adversary, Willie the warden, ever realizing that the communication is taking place. Specifically, we establish that Alice can send O(t) bits (and no more) to Bob in time t over a variety of wireless and optical channels. Moreover, we report experimental results that corroborate the theory.