TrustSAS: A Trustworthy Spectrum Access System for the 3.5 GHz CBRS Band
This addresses privacy issues for secondary users in shared wireless broadband, though it appears incremental as it builds on existing cryptographic and blockchain methods.
The paper tackles the privacy risks in the Citizens Broadband Radio Service (CBRS) band's spectrum access system (SAS) by proposing TrustSAS, a framework that combines cryptographic techniques and blockchain to protect sensitive user information while complying with regulatory requirements, showing it offers high security with reasonable overhead.
As part of its ongoing efforts to meet the increased spectrum demand, the Federal Communications Commission (FCC) has recently opened up 150 MHz in the 3.5 GHz band for shared wireless broadband use. Access and operations in this band, aka Citizens Broadband Radio Service (CBRS), will be managed by a dynamic spectrum access system (SAS) to enable seamless spectrum sharing between secondary users (SUs) and incumbent users. Despite its benefits, SAS's design requirements, as set by FCC, present privacy risks to SUs, merely because SUs are required to share sensitive operational information (e.g., location, identity, spectrum usage) with SAS to be able to learn about spectrum availability in their vicinity. In this paper, we propose TrustSAS , a trustworthy framework for SAS that synergizes state-of-the-art cryptographic techniques with blockchain technology in an innovative way to address these privacy issues while complying with FCC's regulatory design requirements. We analyze the security of our framework and evaluate its performance through analysis, simulation and experimentation. We show that TrustSAS can offer high security guarantees with reasonable overhead, making it an ideal solution for addressing SUs' privacy issues in an operational SAS environment.