42 research outputs found
Control over adversarial packet-dropping communication networks revisited
We revisit a one-step control problem over an adversarial packet-dropping
link. The link is modeled as a set of binary channels controlled by a strategic
jammer whose intention is to wage a `denial of service' attack on the plant by
choosing a most damaging channel-switching strategy. The paper introduces a
class of zero-sum games between the jammer and controller as a scenario for
such attack, and derives necessary and sufficient conditions for these games to
have a nontrivial saddle-point equilibrium. At this equilibrium, the jammer's
optimal policy is to randomize in a region of the plant's state space, thus
requiring the controller to undertake a nontrivial response which is different
from what one would expect in a standard stochastic control problem over a
packet dropping channel.Comment: This paper has been accepted for presentation at the 2014 American
Control Conference, Portland, Orego
Self-triggered Coordination over a Shared Network under Denial-of-Service
The issue of security has become ever more prevalent in the analysis and
design of cyber-physical systems. In this paper, we analyze a consensus network
in the presence of Denial-of-Service (DoS) attacks, namely attacks that prevent
communication among the network agents. By introducing a notion of
Persistency-of-Communication (PoC), we provide a characterization of DoS
frequency and duration such that consensus is not destroyed. An example is
given to substantiate the analysis
On Resilient Control of Nonlinear Systems under Denial-of-Service
We analyze and design a control strategy for nonlinear systems under
Denial-of-Service attacks. Based on an ISS-Lyapunov function analysis, we
provide a characterization of the maximal percentage of time during which
feedback information can be lost without resulting in the instability of the
system. Motivated by the presence of a digital channel we consider event-based
controllers for which a minimal inter-sampling time is explicitly
characterized.Comment: 7 pages, 1 figur
Towards Stabilization of Distributed Systems under Denial-of-Service
In this paper, we consider networked distributed systems in the presence of
Denial-of-Service (DoS) attacks, namely attacks that prevent transmissions over
the communication network. First, we consider a simple and typical scenario
where communication sequence is purely Round-robin and we explicitly calculate
a bound of attack frequency and duration, under which the interconnected
large-scale system is asymptotically stable. Second, trading-off system
resilience and communication load, we design a hybrid transmission strategy
consisting of Zeno-free distributed event-triggered control and Round-robin. We
show that with lower communication loads, the hybrid communication strategy
enables the systems to have the same resilience as in pure Round-robin
Resilient Control under Denial-of-Service
We investigate resilient control strategies for linear systems under
Denial-of-Service (DoS) attacks. By DoS attacks we mean interruptions of
communication on measurement (sensor-to-controller) and/or control
(controller-to-actuator) channels carried out by an intelligent adversary. We
characterize the duration of these interruptions under which stability of the
closed-loop system is preserved. The resilient nature of the control descends
from its ability to adapt the sampling rate to the occurrence of the DoS.Comment: 10 pages, abridged version submitte