Secret Key Generation Between Ambient Backscatter Devices

Loading...
Thumbnail Image
Journal Title
Journal ISSN
Volume Title
A1 Alkuperäisartikkeli tieteellisessä aikakauslehdessä
Date
2023-02-07
Major/Subject
Mcode
Degree programme
Language
en
Pages
13
13456-13468
Series
IEEE Access, Volume 11
Abstract
We analyze secret key generation between ambient backscatter devices where the channel between an ambient transmitter and the backscatter devices is used as a source of randomness. The devices do not need to estimate or measure the channel between themselves, which greatly simplifies the gathering of raw key material. We analyze the eavesdropper's mutual information based on fundamental principles and apply privacy amplification to remove any information that the eavesdropper overheard during the error correction phase. We show how the legitimate users can estimate the eavesdropper's knowledge and trade off between achievable key rate and the eavesdropper's knowledge of the final key. When modeling the channel between the ambient transmitter and the backscatter devices using state-of-the-art 3GPP channel models we show that even in non-line-of-sight channels the distance from legitimate users to an eavesdropper being larger than a few wavelengths is not alone a sufficient security guarantee. This is in contrast with previous secret key generation methods where distance is assumed to prevent the eavesdropper from having any information about the key prior to error correction. Our simulations show that a distance based approach is too optimistic and there is a possibility that the eavesdropper still knows a substantial part of the final key.
Description
Funding Information: This work was supported in part by the Academy of Finland under Grant 334539. Publisher Copyright: © 2013 IEEE.
Keywords
ambient backscatter communication, physical layer security, Secret key generation
Other note
Citation
Lietzen , J & Tirkkonen , O 2023 , ' Secret Key Generation Between Ambient Backscatter Devices ' , IEEE Access , vol. 11 , pp. 13456-13468 . https://doi.org/10.1109/ACCESS.2023.3243063