12 research outputs found
Principles of Physical Layer Security in Multiuser Wireless Networks: A Survey
This paper provides a comprehensive review of the domain of physical layer
security in multiuser wireless networks. The essential premise of
physical-layer security is to enable the exchange of confidential messages over
a wireless medium in the presence of unauthorized eavesdroppers without relying
on higher-layer encryption. This can be achieved primarily in two ways: without
the need for a secret key by intelligently designing transmit coding
strategies, or by exploiting the wireless communication medium to develop
secret keys over public channels. The survey begins with an overview of the
foundations dating back to the pioneering work of Shannon and Wyner on
information-theoretic security. We then describe the evolution of secure
transmission strategies from point-to-point channels to multiple-antenna
systems, followed by generalizations to multiuser broadcast, multiple-access,
interference, and relay networks. Secret-key generation and establishment
protocols based on physical layer mechanisms are subsequently covered.
Approaches for secrecy based on channel coding design are then examined, along
with a description of inter-disciplinary approaches based on game theory and
stochastic geometry. The associated problem of physical-layer message
authentication is also introduced briefly. The survey concludes with
observations on potential research directions in this area.Comment: 23 pages, 10 figures, 303 refs. arXiv admin note: text overlap with
arXiv:1303.1609 by other authors. IEEE Communications Surveys and Tutorials,
201
Solutions for the MIMO Gaussian Wiretap Channel with a Cooperative Jammer
We study the Gaussian MIMO wiretap channel with a transmitter, a legitimate
receiver, an eavesdropper and an external helper, each equipped with multiple
antennas. The transmitter sends confidential messages to its intended receiver,
while the helper transmits jamming signals independent of the source message to
confuse the eavesdropper. The jamming signal is assumed to be treated as noise
at both the intended receiver and the eavesdropper. We obtain a closed-form
expression for the structure of the artificial noise covariance matrix that
guarantees no decrease in the secrecy capacity of the wiretap channel. We also
describe how to find specific realizations of this covariance matrix expression
that provide good secrecy rate performance, even when there is no non-trivial
null space between the helper and the intended receiver. Unlike prior work, our
approach considers the general MIMO case, and is not restricted to SISO or MISO
scenarios