## 4 Applicability on Performance-Constrained Platforms
### Vehicle-to-Vehicle Communication  
Vehicle-to-vehicle (V2V) communication enables timely warnings about approaching vehicles, which is especially useful in situations without a direct line of sight [65]. Each vehicle broadcasts 10 basic safety messages (BSMs) per second [66]. These BSMs contain information on the direction of travel, current location, time, speed, and the status of the gas and brake pedals. Currently, secure wireless communication between vehicles is facilitated through the IEEE 1609.2 standard, which uses elliptic curve digital signature algorithm (ECDSA) for digital signatures.  
Given that the transmission of messages (BSMs) occurs over very short distances, both message transmission and verification must be completed within the order of milliseconds. Therefore, an analysis was conducted to determine whether post-quantum (PQ) digital signature algorithms meet these criteria.  
Regarding quick signature verification, Dilithium and Falcon appeared to be suitable replacements for ECDSA. However, when the size of the signature was also considered, Dilithium became inapplicable as its signature size exceeds the message size (2304 bytes) defined in IEEE 802.11p. Falcon was proposed as the most appropriate algorithm for V2V communication [66].  
Similar conclusions were reached in [67], where the authors evaluated the performance of Dilithium and Falcon for over-the-air (OTA) updates used in vehicle-to-everything (V2X) communication infrastructures. Namely, an experimental evaluation was conducted on the Xilinx Zynq Ultrascale+ ZCU102 board, tailored for automotive applications, to assess the performance of the Dilithium and Falcon cryptographic algorithms. The findings indicatedthat Falcon outperformed Dilithium in both signature verification latency and signature byte footprint.  
In a paper [68], the authors achieved significant optimizations of the Dilithium algorithm for Aurix implementation, specifically targeting automotive applications. They managed to reduce the computational time for key generation, signature creation, and verification across varying security levels. Specifically, they reported time reductions in the range from 23% to 29% for key generation, from 12% to 19% for signature creation, and from 18% to 26% for signature verification.  
A paper [69] discussed the practical integration of Dilithium into multiprocessor system-on-chip (MPSoC) architectures, commonly employed in automotive environments and managed by a commercial real-time operating system (RTOS). Experimental data revealed that deploying Dilithium on a multi-core framework significantly enhanced the performance metrics--yielding improvements of up to 48% in key generation, 34% in the signature process, and 42% in verification tasks--when contrasted with single-core configurations.  
Other researchers [70] investigated the constraints of conforming to IEEE 1609.2 standards in the context of the WAVE protocol for vehicle-to-vehicle (V2V) communications. They identified the inability to incorporate cryptographic schemes with large signature sizes as a fundamental limitation. To circumvent this issue, they introduced a technique termed \"split way for Crystals-Dilithium,\" aimed at ensuring the WAVE protocol's integrity while adhering to maximum packet size restrictions.