This work considers the two way wiretap channel in which two legitimate
users, Alice and Bob, wish to exchange messages securely in the presence of a
passive eavesdropper Eve. In the full duplex scenario, where each node can
transmit and receive simultaneously, we obtain new achievable secrecy rate
regions based on the idea of allowing the two users to jointly optimize their
channel prefixing distributions and binning codebooks; in addition to key
sharing. The new regions are shown to be strictly larger than the known ones
for a wide class of discrete memoryless and Gaussian channels.

Adding location to the available information enables a new category of
applications. With the constrained battery on cell phones, energy-efficient
localization becomes an important challenge. In this paper we introduce a
low-energy calibration-free localization scheme based on the available internal
sensors in many of today's phones. We start by energy profiling the different
sensors that can be used for localization.

In this paper we propose distributed flooding-based storage algorithms for
large-scale wireless sensor networks. Assume a wireless sensor network with $n$
nodes that have limited power, memory, and bandwidth. Each node is capable of
both sensing and storing data. Such sensor nodes might disappear from the
network due to failures or battery depletion. Hence it is desired to design
efficient schemes to collect data from these $n$ nodes. We propose two
distributed storage algorithms (DSA's) that utilize network flooding to solve
this problem.

This paper develops a new physical layer framework for secure two-way
wireless communication in the presence of a passive eavesdropper, i.e., Eve.
Our approach achieves perfect information theoretic secrecy via a novel
randomized scheduling and power allocation scheme. The key idea is to allow
Alice and Bob to send symbols at random time instants. While Alice will be able
to determine the symbols transmitted by Bob, Eve will suffer from ambiguity
regarding the source of any particular symbol. This desirable ambiguity is
enhanced, in our approach, by randomizing the transmit power level.