  Resource-constrained devices increasingly rely on wireless communication for
the reliable and low-latency transmission of short messages. However,
especially the implementation of adequate integrity protection of time-critical
messages places a significant burden on these devices. We address this issue by
proposing BP-MAC, a fast and memory-efficient approach for computing message
authentication codes based on the well-established Carter-Wegman construction.
Our key idea is to offload resource-intensive computations to idle phases and
thus save valuable time in latency-critical phases, i.e., when new data awaits
processing. Therefore, BP-MAC leverages a universal hash function designed for
the bitwise preprocessing of integrity protection to later only require a few
XOR operations during the latency-critical phase. Our evaluation on embedded
hardware shows that BP-MAC outperforms the state-of-the-art in terms of latency
and memory overhead, notably for small messages, as required to adequately
protect resource-constrained devices with stringent security and latency
requirements.
