Embedded cryptography stands or falls on entropy quality, yet small devices have few trustworthy sources and little tolerance for heavyweight protocols. We build a Quantum Entropy as a Service (QEaaS) system that moves QRNG-derived entropy from a Quantis device to ESP32-class clients over post-quantum-secured channels. On the server side, the design exposes two paths: direct quantum entropy through a custom OpenSSL provider and mixed entropy through the Linux system pool. On the client side, we extend libcoap's Zephyr support, integrate wolfSSL-based DTLS 1.3 into the CoAP stack, and add a BLAKE2s entropy pool that preserves the standard Zephyr extraction interface while introducing an injection API for server-provided entropy. Benchmarks on ESP32 hardware, targeting 100 iterations per configuration, show that ML-KEM-512 completes a DTLS 1.3 handshake in 313 ms on average without certificate verification, 35% faster than ECDHE P-256. Pairing ML-KEM-512 with ML-DSA-44 lowers the mean to 225 ms. Certificate verification adds roughly 194 ms for ECDSA but only 17 ms for ML-DSA-44, so the fully post-quantum configuration remains 63% faster than classical ECDHE P-256 with ECDSA even under full verification. Local BLAKE2s pool operations stay below 0.1 ms combined. On this platform, post-quantum key exchange and authentication are not only feasible; they are faster than the classical baseline.
Embedded cryptography stands or falls on entropy quality, yet small devices have few trustworthy sources and little tolerance for heavyweight protocols. We build a Quantum Entropy as a Service (QEaaS) system that moves QRNG-derived entropy from a Quantis device to ESP32-class clients over post-quantum-secured channels. On the server side, the design exposes two paths: direct quantum entropy through a custom OpenSSL provider and mixed entropy through the Linux system pool. On the client side, we extend libcoap's Zephyr support, integrate wolfSSL-based DTLS 1.3 into the CoAP stack, and add a BLAKE2s entropy pool that preserves the standard Zephyr extraction interface while introducing an injection API for server-provided entropy. Benchmarks on ESP32 hardware, targeting 100 iterations per configuration, show that ML-KEM-512 completes a DTLS 1.3 handshake in 313 ms on average without certificate verification, 35% faster than ECDHE P-256. Pairing ML-KEM-512 with ML-DSA-44 lowers the mean to 225 ms. Certificate verification adds roughly 194 ms for ECDSA but only 17 ms for ML-DSA-44, so the fully post-quantum configuration remains 63% faster than classical ECDHE P-256 with ECDSA even under full verification. Local BLAKE2s pool operations stay below 0.1 ms combined. On this platform, post-quantum key exchange and authentication are not only feasible; they are faster than the classical baseline.
Embedded cryptography stands or falls on entropy quality, yet small devices have few trustworthy sources and little tolerance for heavyweight protocols. We build a Quantum Entropy as a Service (QEaaS) system that moves QRNG-derived entropy from a Quantis device to ESP32-class clients over post-quantum-secured channels. On the server side, the design exposes two paths: direct quantum entropy through a custom OpenSSL provider and mixed entropy through the Linux system pool. On the client side, we extend libcoap's Zephyr support, integrate wolfSSL-based DTLS 1.3 into the CoAP stack, and add a BLAKE2s entropy pool that preserves the standard Zephyr extraction interface while introducing an injection API for server-provided entropy. Benchmarks on ESP32 hardware, targeting 100 iterations per configuration, show that ML-KEM-512 completes a DTLS 1.3 handshake in 313 ms on average without certificate verification, 35% faster than ECDHE P-256. Pairing ML-KEM-512 with ML-DSA-44 lowers the mean to 225 ms. Certificate verification adds roughly 194 ms for ECDSA but only 17 ms for ML-DSA-44, so the fully post-quantum configuration remains 63% faster than classical ECDHE P-256 with ECDSA even under full verification. Local BLAKE2s pool operations stay below 0.1 ms combined. On this platform, post-quantum key exchange and authentication are not only feasible; they are faster than the classical baseline.
The emergence of cryptographically relevant quantum computers threatens the security ofclassical public-key cryptography, necessitating the transition toward post-quantum cryptographic (PQC)algorithms standardized by NIST. At the same time, modern Internet protocols such as HTTP/3—runningover the QUIC transport protocol—are becoming widely deployed, offering reduced latency and improvedreliability compared to traditional TCP+TLS stacks. Ensuring that HTTP/3 infrastructure remains secure inthe post-quantum era requires practical implementations that integrate PQC algorithms without causingprohibitive performance overheads. In this study, we present the development of a PQC–enabled Apacheweb server that supports HTTP/3 through a custom OpenSSL 3.5.4 provider embedding the NISTstandardized ML-KEM and ML-DSA algorithms. Our implementation integrates PQC primitives into theQUIC handshake via modified OpenSSL EVP interfaces and enables PQC-based certificates and keyencapsulation mechanisms within a Caddy reverse proxy + Apache server architecture. Performanceevaluations were conducted on heterogeneous hardware, including a Raspberry Pi 4 and an Intel-baseddesktop system, under realistic network conditions. Experimental results show that ML-KEM and MLDSA introduce moderate handshake latency (≈18%) and minimal throughput reduction (4–8%). Across allconfigurations, HTTP/3's multiplexed, UDP-based design mitigated PQC-related delays, maintaining morethan 90% of classical throughput. The results demonstrate that integrating standardized PQC algorithmsinto modern web servers is both feasible and efficient, validating HTTP/3 as a strong foundation forquantum-resilient Internet communication. This work provides an operational reference for deploying PQCwithin web infrastructures and highlights pathways for future enhancements such as hybrid key exchange,certificate compression, and hardware acceleration.
As quantum technologies advance, the security of popular cryptographic protocols becomes more threatened by the capabilities of Cryptographically Relevant Quantum Computers (CRQCs). In this scenario, Post-Quantum Cryptography (PQC) has become a potential solution to prolong the life of existing Public Key Infrastructure (PKI) systems. However, PQC protocols depend on high-quality randomness for key generation and encapsulation procedures, with the quality of the entropy source potentially having a profound impact on the security of the overall system. In this work, we demonstrate a proof-of-concept enabling the incorporation of Quantum Random Number Generation (QRNG) devices within communication networks using PQC-based Transport Layer Security (TLS).Using open-source cryptographic libraries and commercial QRNG hardware, we demonstrate their use as entropy sources via an Entropy-as-a-Service (EaaS) model. We highlight two particular use cases: a fully virtualized private PKI network and a connection to an external PQC-enabled server. Experimental results show that EaaS QRNG enables real-time entropy monitoring and quality assessment in cryptographic management systems, with negligible impact on TLS handshake time.
The advancement of quantum computing creates a big threat to classical cryptographic protocols, including TLS, which is responsible for secure internet communications. While recent industry and academic efforts have focused on integrating lattice-based post-quantum key encapsulation mechanisms (KEMs) such as Kyber+X25519 into hybrid TLS handshakes, these approaches often prioritize performance at the cost of cryptanalytic diversity. Code-based KEMs, despite their proven security measure they remain underexplored in hybrid frameworks due to some limitations like large key sizes and integration complexity. This paper proposes a novel hybrid TLS framework that explicitly incorporates code-based post-quantum cryptography—specifically McEliece—alongside classical key exchange mechanisms. The framework introduces a dual-handshake mechanism, adaptive parameter selection, and seamless fallback negotiation, enabling flexible deployment across heterogeneous networks while ensuring backward compatibility. Integration with Quantum Random Number Generators (QRNGs) and multifactor authentication further increases entropy quality and session security. We implemented and evaluated the framework using an OpenSSL-OQS integration. We measure handshake latency, CPU utilization, memory usage, and throughput across emulated and real-world testbeds. Results show that the proposed hybrid approach achieves up to 30% lower latency and significantly reduced resource overhead compared to pure post-quantum TLS variants, while maintaining near-classical efficiency levels. Mathematical modeling formalizes these trade-offs which offers a foundation for optimizing deployment in both resource-constrained IoT devices and high-performance servers. By advancing cryptographic diversity and aligning with emerging NIST and IETF standardization efforts, the proposed framework provides a practical pathway toward quantum-resilient secure communication.It shows that code-based post-quantum cryptography can be added to current TLS systems without any problems, keeping security, performance, and compatibility in mind as we get ready for the quantum age.
The integration of NIST-standardized lattice-based cryptographic algorithms (ML-KEM and ML-DSA) into TLS 1.3 enables post-quantum secure authentication for Industrial IoT (IIoT) environments. This work implements these algorithms within the X.509 certificate infrastructure and evaluates their performance on resource-constrained IIoT hardware (Raspberry Pi 4). Experimental measurements covering key generation, encapsulation, decapsulation, and signature operations were obtained using a liboqs-enabled TLS 1.3 stack. The results show that PQ TLS 1.3 achieves comparable handshake latency to conventional TLS on IIoT-class gateways, with certificate size identified as the dominant overhead. These findings confirm the practicality of post-quantum authentication in IIoT systems while acknowledging limitations related to the hardware scope and simulated networking. Future work will extend validation to field deployments and additional PQC candidates.
The migration of remote-access and industrial communication systems from classical public-key cryptography to post-quantum cryptography (PQC) requires careful evaluation at both the protocol and system levels. This paper presents PQC-E2E-CA, a system-level evaluation framework for reviewing post-quantum and hybrid cryptographic configurations in Secure Shell (SSH). The framework integrates OQS-enabled OpenSSH and OpenSSL with Linux netem network emulation, automated experiment execution, SCP integrity verification, and statistical post-processing. The evaluation separates key exchange behavior from host key authentication. Specifically, it measures ML-KEM and hybrid ML-KEM as SSH key exchange mechanisms, and ML-DSA as a host-key signature mechanism. Experiments are conducted under controlled RTT and packet-loss conditions using a gateway virtualised client-server testbed. The results show that ML-KEM and hybrid ML-KEM can be integrated into SSH without prohibitive application-level session setup overhead in the evaluated environment. Among the evaluated configurations, ML-KEM-768 demonstrates comparatively lower SSH session establishment latency at 50 ms RTT with 0% packet loss. ML-DSA-44 achieves the lowest host-key authentication latency under the same conditions and maintains relatively stable performance at 150 ms RTT with 5% packet loss. SCP throughput results for 100 MB and 200 MB transfers indicate that sustained transfer performance is mainly influenced by RTT and transport-layer dynamics using a single dominant key exchange configuration. These findings support migration toward standardized post-quantum mechanisms in SSH-based gateway and remote-access environments, provided that algorithm choice and system configuration are validated under representative workloads and network conditions.