  This paper presents a reconfigurable cryptographic engine that implements the
DTLS protocol to enable end-to-end security for IoT. This implementation of the
DTLS engine demonstrates 10x reduction in code size and 438x improvement in
energy-efficiency over software. Our ECC primitive is 237x and 9x more
energy-efficient compared to software and state-of-the-art hardware
respectively. Pairing the DTLS engine with an on-chip RISC-V allows us to
demonstrate applications beyond DTLS with up to 2 orders of magnitude energy
savings.
