3,741 research outputs found
Jamming Games in the MIMO Wiretap Channel With an Active Eavesdropper
This paper investigates reliable and covert transmission strategies in a
multiple-input multiple-output (MIMO) wiretap channel with a transmitter,
receiver and an adversarial wiretapper, each equipped with multiple antennas.
In a departure from existing work, the wiretapper possesses a novel capability
to act either as a passive eavesdropper or as an active jammer, under a
half-duplex constraint. The transmitter therefore faces a choice between
allocating all of its power for data, or broadcasting artificial interference
along with the information signal in an attempt to jam the eavesdropper
(assuming its instantaneous channel state is unknown). To examine the resulting
trade-offs for the legitimate transmitter and the adversary, we model their
interactions as a two-person zero-sum game with the ergodic MIMO secrecy rate
as the payoff function. We first examine conditions for the existence of
pure-strategy Nash equilibria (NE) and the structure of mixed-strategy NE for
the strategic form of the game.We then derive equilibrium strategies for the
extensive form of the game where players move sequentially under scenarios of
perfect and imperfect information. Finally, numerical simulations are presented
to examine the equilibrium outcomes of the various scenarios considered.Comment: 27 pages, 8 figures. To appear, IEEE Transactions on Signal
Processin
Vulnerability analysis of satellite-based synchronized smart grids monitoring systems
The large-scale deployment of wide-area monitoring systems could play a strategic role in supporting the evolution of traditional power systems toward smarter and self-healing grids. The correct operation of these synchronized monitoring systems requires a common and accurate timing reference usually provided by a satellite-based global positioning system. Although these satellites signals provide timing accuracy that easily exceeds the needs of the power industry, they are extremely vulnerable to radio frequency interference. Consequently, a comprehensive analysis aimed at identifying their potential vulnerabilities is of paramount importance for correct and safe wide-area monitoring system operation. Armed with such a vision, this article presents and discusses the results of an experimental analysis aimed at characterizing the vulnerability of global positioning system based wide-area monitoring systems to external interferences. The article outlines the potential strategies that could be adopted to protect global positioning system receivers from external cyber-attacks and proposes decentralized defense strategies based on self-organizing sensor networks aimed at assuring correct time synchronization in the presence of external attacks
One Breaker is Enough: Hidden Topology Attacks on Power Grids
A coordinated cyber-attack on grid meter readings and breaker statuses can
lead to incorrect state estimation that can subsequently destabilize the grid.
This paper studies cyber-attacks by an adversary that changes breaker statuses
on transmission lines to affect the estimation of the grid topology. The
adversary, however, is incapable of changing the value of any meter data and
can only block recorded measurements on certain lines from being transmitted to
the control center. The proposed framework, with limited resource requirements
as compared to standard data attacks, thus extends the scope of cyber-attacks
to grids secure from meter corruption. We discuss necessary and sufficient
conditions for feasible attacks using a novel graph-coloring based analysis and
show that an optimal attack requires breaker status change at only ONE
transmission line. The potency of our attack regime is demonstrated through
simulations on IEEE test cases.Comment: 5 pages, 5 figures, Accepted to the IEEE PES General Meeting 201
Jamming aided Generalized Data Attacks: Exposing Vulnerabilities in Secure Estimation
Jamming refers to the deletion, corruption or damage of meter measurements
that prevents their further usage. This is distinct from adversarial data
injection that changes meter readings while preserving their utility in state
estimation. This paper presents a generalized attack regime that uses jamming
of secure and insecure measurements to greatly expand the scope of common
'hidden' and 'detectable' data injection attacks in literature. For 'hidden'
attacks, it is shown that with jamming, the optimal attack is given by the
minimum feasible cut in a specific weighted graph. More importantly, for
'detectable' data attacks, this paper shows that the entire range of relative
costs for adversarial jamming and data injection can be divided into three
separate regions, with distinct graph-cut based constructions for the optimal
attack. Approximate algorithms for attack design are developed and their
performances are demonstrated by simulations on IEEE test cases. Further, it is
proved that prevention of such attacks require security of all grid
measurements. This work comprehensively quantifies the dual adversarial
benefits of jamming: (a) reduced attack cost and (b) increased resilience to
secure measurements, that strengthen the potency of data attacks.Comment: 11 pages, 8 figures, A version of this will appear in HICSS 201
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