Ultra Lightweight Multiple-Time Digital Signature for the Internet of Things Devices

Abstract

Digital signatures are basic cryptographic tools to provide authentication and integrity in the emerging ubiquitous systems in which resource-constrained devices are expected to operate securely and efficiently. However, existing digital signatures might not be fully practical for such resource-constrained devices (e.g., medical implants) that have energy limitations. Some other computationally efficient alternatives (e.g., one-time/multipletime signatures) may introduce high memory and/or communication overhead due to large private key and signature sizes.In this paper, our contributions are two-fold: First, we develop a new lightweight multiple-time digital signature scheme called Signer Efficient Multiple-time Elliptic Curve Signature (SEMECS), which is suitable for resource-constrained embedded devices. SEMECS achieves optimal signature and private key sizes for an EC-based signature without requiring any EC operation (e.g., EC scalar multiplication or addition) at the signer. We prove SEMECS is secure (in random oracle model) with a tight security reduction. Second, we fully implemented SEMECS on 8-bit AVR microprocessor with a comprehensive energy consumption analysis and comparison. Our experiments confirm up to 19× less battery-consumption for SEMECS as compared to its fastest (full-time) counterpart, SchnorrQ, while offering significant performance advantages over its multipletime counterparts in various fronts. We open-source our implementation for public testing and adoption.

LiS: Lightweight Signature Schemes for Continuous Message Authentication in Cyber-Physical Systems

“…Also, compared with Schnorr's signature, our signing algorithm is more efficient as Schnorr's signature requires modular exponentiation, which does not fit any resource-constrained devices in CPS [27]. Although our schemes' the key size of the signer is slightly longer than that of SEMECS [13], we outperform SEMECS with respect to the other performance metrics.…”

“…Comparison. Here we compare the security features and performance between our signature schemes and some related works, including Schnorr [9], Yao and Zhao's Γ-1 and Γ-2 [12], and SEMECS [13]. Let 'CMAu' and 'PV' denote continuous message authentication and public verifiability, respectively.…”

“…In 2019, Yavuz and Ozmen [13] proposed a lightweight signature scheme called SEMECS, which is adapted from the Schnorr signature. To facilitate the signature generation, SEMECS particularly chain up the exponents of verification keys, such that r j := H (r j−1 ), where the j-th verification key is computed as д r j and д is the group generator of a cyclic abelian group, so that it can pre-compute all verification keys in advance.…”

“…It is suggested in [11][12][13] that the offline phase for computing D can be carried out either during the device manufacturing process or by the device itself as a background computation. However, none of these two ways of generating D is perfect in CPS.…”

Continuous Entity Authentication in the Internet of Things Scenario

“…However, their proposal still requires a storage which is linear in the number of signatures that the signer can generate, making the scheme unsuitable for storage-limited signer devices. Other solutions in the online/offline paradigm have been proposed in [20,21]. Unfortunately, none of the above solutions is suitable in a scenario where the signer is a device having both limited computing power and low storage capability, such as an IoT device.…”