NSF Award
2331936
The problem of radio spectrum congestion limits the growth of wireless communications and sensing, which is essential for all aspects of modern society. This project investigates use of Distributed Ledger Technology (DLT), of which the famous example is Blockchain, to support automated and secure dynamic allocation mechanisms that enhance spectrum efficiency and availability. The project explores use of DLT for interaction among mutually distrustful Zone Management Systems (ZMS), a general category of automatic spectrum management mechanisms that includes currently deployed Spectrum Access Systems and future derivatives. Multiple ZMS must collaborate even though they do not trust each other, as in current SAS where competing administrators manage a single shared band, or in future radio dynamic zones like a radio telescope observatory where the observatory ZMS trades spectrum back and forth with the ZMS for a neighboring mobile wireless operator. Use of DLT enables a new collaboration approach that reaches agreement faster, delivers more optimal outcomes, is better protected against malicious ZMS, is more auditable by regulators, and enhances data privacy for spectrum users compared to current SAS designs. This project investigates DLT for ZMS collaboration from technical and policy perspectives and seeks to impact future Federal Communications Commission regulations.<br/><br/>Collaboration among multiple SAS today relies on each SAS running the same decision algorithm on the same input data. The new architecture explored in this project assumes each ZMS runs a proprietary decision algorithm on proprietary data – which increases efficiency while enhancing innovation and flexibility – and achieves coherent spectrum assignment decisions through a distributed agreement process and an auditable record to prevent cheating. Within the new architecture, this project focuses on policies and enabling technologies for privacy-preserving information exchange and Byzantine-resilient collaboration among participating ZMS. Project work includes: (1) Evaluate multiple DLT technologies such as proof-of-stake systems that are more energy-efficient than Blockchain. (2) Identify essential data that must be exchanged among ZMS. (3) Develop a lightweight (i.e., time bounded), secure, reliable, and trustworthy DLT-based protocol for assignments. (4) Explore an off-chain secure contract execution approach to reduce protocol execution complexity. (5) Apply privacy-enhancing technologies including multiparty computation and trusted execution environments to safeguard the privacy of ZMS proprietary data and algorithms and spectrum users. (6) Investigate methods to satisfy FCC policy goals such as ways to assure contiguous channel and geographic assignments.<br/><br/>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.
