EP-CuMAC: Energy and Performance-Efficient Integrity Protection for Narrow-Band IoT

Narrowband Internet of Things (NB-IoT) is a LPWAN radio standard developed by 3GPP to provide devices with longer battery life and broader coverage. Many authors have proposed algorithms to maximise battery life by optimising devices’ Active periods. However, more research is required to develop integrity-protection algorithms for NB-IoT and study their impact on battery life. NB-IoT, being bandwidth-constrained, transmits data as truncated packets at discrete intervals to maximise battery life. However, truncated MACs reduce cryptographic strength leading to brute-force attacks. Cumulative MAC (CuMAC), generating 256-bit authentication tags by aggregating truncated MACs, alleviates this limitation. However, CuMAC is prone to replay attacks and reduced performance due to re-transmissions, resulting in delayed responses, packet loss and battery overhead.