3 research outputs found
Secure Routing with Power Optimization for Ad-hoc Networks
In this paper, we consider the problem of joint secure routing and transmit
power optimization for a multi-hop ad-hoc network under the existence of
randomly distributed eavesdroppers following a Poisson point process (PPP).
Secrecy messages are delivered from a source to a destination through a
multi-hop route connected by multiple legitimate relays in the network. Our
goal is to minimize the end-to-end connection outage probability (COP) under
the constraint of a secrecy outage probability (SOP) threshold, by optimizing
the routing path and the transmit power of each hop jointly. We show that the
globally optimal solution could be obtained by a two-step procedure where the
optimal transmit power has a closed-form and the optimal routing path can be
found by Dijkstra's algorithm. Then a friendly jammer with multiple antennas is
applied to enhance the secrecy performance further, and the optimal transmit
power of the jammer and each hop of the selected route is investigated. This
problem can be solved optimally via an iterative outer polyblock approximation
with one-dimension search algorithm. Furthermore, suboptimal transmit powers
can be derived using the successive convex approximation (SCA) method with a
lower complexity. Simulation results show the performance improvement of the
proposed algorithms for both non-jamming and jamming scenarios, and also reveal
a non-trivial trade-off between the numbers of hops and the transmit power of
each hop for secure routing.Comment: 13 pages, 10 figures, to be published in IEEE Transactions on
Communication
Can a Multi-Hop Link Relying on Untrusted Amplify-and-Forward Relays Render Security?
Cooperative relaying is utilized as an efficient method for data
communication in wireless sensor networks and the Internet of Things (IoT).
However, sometimes due to the necessity of multi-hop relaying in such
communication networks, it is challenging to guarantee the secrecy of
cooperative transmissions when the relays may themselves be eavesdroppers,
i.e., we may face with the untrusted relaying scenario where the relays are
both necessary helpers and potential adversary. To obviate this issue, a new
cooperative jamming scheme is proposed in this paper, in which the data can be
confidentially communicated from the source to the destination through multiple
untrusted relays. In our proposed secure transmission scheme, all the
legitimate nodes contribute to providing secure communication by intelligently
injecting artificial noises to the network in different communication phases.
For the sake of analysis, we consider a multi-hop untrusted relaying network
with two successive intermediate nodes, i.e, a three-hop communications
network. Given this system model, a new closed-form expression is presented in
the high signal-to-noise ratio (SNR) region for the Ergodic secrecy rate (ESR).
Furthermore, we evaluate the high SNR slope and power offset of the ESR to gain
an insightful comparison of the proposed secure transmission scheme and the
state-of-arts. Our numerical results highlight that the proposed secure
transmission scheme provides better secrecy rate performance compared with the
two-hop untrusted relaying as well as the direct transmission schemes.Comment: 24 pages, 9 figures, submitted for journal publicatio
Secrecy and Covert Communications against UAV Surveillance via Multi-Hop Networks
The deployment of unmanned aerial vehicle (UAV) for surveillance and
monitoring gives rise to the confidential information leakage challenge in both
civilian and military environments. The security and covert communication
problems for a pair of terrestrial nodes against UAV surveillance are
considered in this paper. To overcome the information leakage and increase the
transmission reliability, a multi-hop relaying strategy is deployed. We aim to
optimize the throughput by carefully designing the parameters of the multi-hop
network, including the coding rates, transmit power, and required number of
hops. In the secure transmission scenario, the expressions of the connection
probability and secrecy outage probability of an end-to-end path are derived
and the closed-form expressions of the optimal transmit power, transmission and
secrecy rates under a fixed number of hops are obtained. In the covert
communication problem, under the constraints of the detection error rate and
aggregate power, the sub-problem of transmit power allocation is a convex
problem and can be solved numerically. Simulation shows the impact of network
settings on the transmission performance. The trade-off between
secrecy/covertness and efficiency of the multi-hop transmission is discussed
which leads to the existence of the optimal number of hops.Comment: 29 pages, 11 figures, accepted by IEEE Transactions on Communications
for future publicatio