CAREER: Foundations of Secure Communication in mmWave Networks

Today, an ever-growing number of services rely on the use of the wireless medium to transfer sheer volumes of data that is inherently private, such as e-health data and credit card information. One solution to support high data rates consists of utilizing the communication bands in the millimeter-wave (mmWave) spectrum, that is, the abundant range of frequencies from 30 GHz to 300 GHz.

Due to its openness and shared nature, however, the wireless medium is highly vulnerable to eavesdropping attacks. The traditional assumption that an eavesdropping adversary will have limited computational capabilities is placed in doubt by recent trends and advances in (quantum) computing. Conversely, in a large multi-hop mmWave network, it is reasonable to assume that an eavesdropper can intercept transmissions only over a subset of the links over which she has to be physically present.

The goal of this project is to provide simple yet powerful abstractions of mmWave networks and to design information-theoretic optimal transmission protocols that are unconditionally secure against an external eavesdropper with unbounded computational capabilities but limited network presence. The research is highly integrated with educational activities that leverage the unique opportunities presented by the awardee institution.

This project develops an information-theoretic framework that captures the essentials of multi-hop mmWave communication and eavesdroppers' capabilities. The first objective consists of characterizing the maximum secure information flow over single-source single-destination multi-hop mmWave networks with the derivation of converse bounds and the design of novel transmission schemes.

A key aspect is the characterization of the trade-off between parameters that account for the computational and processing capabilities at the nodes and afford a target end-to-end secure rate. The second objective consists of developing information-theoretic optimal secure communication protocols for multi-hop mmWave networks where multiple legitimate source-destination pairs share the same resources and wish to securely communicate among themselves.

Towards this end, the benefits of cooperation in generating randomness and sharing the resources, together with the advantages of employing common keys in place of private keys, are investigated to develop architectures that have provably optimal scaling laws for the secure flow of information over large and dense mmWave networks. The wide range of applications in which mmWave communication is foreseen to play a key role, together with the urgent need of protocols to maintain the confidentiality of the exchanged data, render this project relevant to global industrial and societal needs.

This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.