  In this emerging data-driven world, secure and ubiquitous authentication
mechanisms are necessary prior to any confidential information delivery.
Biometric authentication has been widely adopted as it provides a unique and
non-transferable solution for user authentication. In this article, the authors
envision the need for an in-field, remote and on-demand authentication system
for a highly mobile and tactical environment, such as critical information
delivery to soldiers in a battlefield. Fingerprint-based in-field biometric
authentication combined with the conventional password-based techniques would
ensure strong security of critical information delivery. The proposed in-field
fingerprint authentication system involves: (i) wearable fingerprint sensor,
(ii) template extraction (TE) algorithm, (iii) data encryption, (iv) on-body
and long-range communications, all of which are subject to energy constraints
due to the requirement of small form-factor wearable devices. This paper
explores the design space and provides an optimized solution for resource
allocation to enable energy-efficient in-field fingerprint-based
authentication. Using Human Body Communication (HBC) for the on-body data
transfer along with the analytics (TE algorithm) on the hub allows for the
maximum lifetime of the energy-sparse sensor. A custom-built hardware prototype
using COTS components demonstrates the feasibility of the in-field fingerprint
authentication framework.
