Covert Routing with DSSS Signaling Against Cycle Detectors

TL;DR

This paper develops a framework for covert multi-hop wireless communication using DSSS signaling to optimize route selection and resource allocation against cycle detectors, balancing covertness, latency, and reliability.

Contribution

It introduces an optimal joint bandwidth, power, and spreading gain allocation method for covert routing under QoS constraints, with a novel equivalence between covertness and detection SNR formulations.

Findings

Latency increases exponentially with covertness requirement.

Latency growth is super-linear with packet size M.

Cycle and energy detectors affect latency differently based on message length.

Abstract

This paper investigates covert multi-hop communication in wireless networks where an adversary employs a cyclostationary (cycle) detector to reveal hidden transmissions. The covert route employs direct sequence spread spectrum (DSSS) signaling to ensure either maximum end-to-end covertness maximization or minimum latency minimization-under quality-of-service (QoS) and link budget constraints. Optimal bandwidth, transmit power, and spreading gain for each hop jointly satisfy reliability and either rate or covertness requirements. We show the equivalence between the covertness and the detection SNR gain-based widest-path formulations, and, hence, enabling efficient route computation. Numerical simulations in a realistic 3D environment illustrate that (i) end-to-end latency increases exponentially with the covertness requirement, (ii) the end-to-end latency increase is super-linear with the packet size M, and (iii) cycle and energy detectors impose different latency behavior as a function of the message length and the covertness requirement. The proposed framework provides important insights into resource allocation and routing design for covert networks against advanced detection adversaries.