The transition to a cloud-native 5G Service-Based Architecture (SBA) improves scalability but exposes control-plane signaling to emerging quantum threats, including Harvest-Now, Decrypt-Later (HNDL) attacks. While NIST has standardized post-quantum cryptography (PQC), practical, deployable integration in operational 5G cores remains underexplored. This work experimentally integrates NIST-standardized ML-KEM-768 and ML-DSA into an open-source 5G core (free5GC) using a sidecar proxy pattern that preserves unmodified network functions (NFs). Implemented on free5GC, we compare three deployments: (i) native HTTPS/TLS, (ii) TLS sidecar, and (iii) PQC-enabled sidecar. Measurements at the HTTP/2 request-response boundary over repeated independent runs show that PQC increases end-to-end Service-Based Interface (SBI) latency to approximately 54 ms, adding a deterministic 48-49 ms overhead relative to the classical baseline, while maintaining tightly bounded variance (IQR <= 0.2 ms, CV < 0.4%). We also quantify the impact of Certification Authority (CA) security levels, identifying certificate validation as a tunable contributor to overall delay. Overall, the results demonstrate that sidecar-based PQC insertion enables a non-disruptive and operationally predictable migration path for quantum-resilient 5G signaling.
The transition to a cloud-native 5G Service-Based Architecture (SBA) improves scalability but exposes control-plane signaling to emerging quantum threats, including Harvest-Now, Decrypt-Later (HNDL) attacks. While NIST has standardized post-quantum cryptography (PQC), practical, deployable integration in operational 5G cores remains underexplored. This work experimentally integrates NIST-standardized ML-KEM-768 and ML-DSA into an open-source 5G core (free5GC) using a sidecar proxy pattern that preserves unmodified network functions (NFs). Implemented on free5GC, we compare three deployments: (i) native HTTPS/TLS, (ii) TLS sidecar, and (iii) PQC-enabled sidecar. Measurements at the HTTP/2 request-response boundary over repeated independent runs show that PQC increases end-to-end Service-Based Interface (SBI) latency to approximately 54 ms, adding a deterministic 48-49 ms overhead relative to the classical baseline, while maintaining tightly bounded variance (IQR <= 0.2 ms, CV < 0.4%). We also quantify the impact of Certification Authority (CA) security levels, identifying certificate validation as a tunable contributor to overall delay. Overall, the results demonstrate that sidecar-based PQC insertion enables a non-disruptive and operationally predictable migration path for quantum-resilient 5G signaling.
As mobile networks evolve toward future disaggregated architectures and 6G systems, quantum computing poses an existential threat to the current cryptographic foundations underpinning Service-Based Architecture (SBA) deployments. This paper presents a standards-driven analysis of integrating Post-Quantum Cryptography (PQC) into future mobile core networks, directly informing ongoing NIST, IETF, and 3GPP standardization efforts. We examine current security specifications and identify critical vulnerabilities in SBA interfaces that are susceptible to “harvest-now, decrypt-later” attacks. Our framework maps PQC algorithm recommendations to existing standards clauses, proposing concrete specification updates for future release adoption. We assess the impact of standardization by validating the performance of NIST-standardized post-quantum algorithms across representative SBA interfaces, demonstrating that quantum-safe migrations can meet operational requirements for future mobile cores. Experimental results indicate that selected post-quantum configurations deliver acceptable performance for control-plane functions, supporting edge-cloud continuum deployments. We present a standards migration roadmap that addresses PKI lifecycle management, inter-operator security protocols, and coordination requirements between standards bodies.
5th Generation (5G) cellular networks have been adopted around the world since the rollout began around 2019. It brought with it many innovations and new services, such as Enhanced Mobile Broadband (eMBB), Ultra Reliable and Low Latency Communications (URLLC), and Massive Internet of Things (mIoT). 5G also introduced a more scalable approach to network operations using fully software-based Virtualized Network Functions (VNF) in Core Networks (CN) rather than the prior hardware-based approach. However, while this shift towards a fully software-based system design provides numerous significant benefits, such as increased interoperability, scalability, and cost-effectiveness, it also brought with it an increased cybersecurity risk. Security is crucial to maintaining trust between vendors, operators, and consumers. Cyberattacks are rapidly increasing in number and sophistication, and we are seeing a shift towards zero-trust approaches. This means that even communications between VNFs inside a 5G core have to be scrutinized and hardened against attacks, especially with the advent of quantum computers. The National Institute of Standards and Technology (NIST), over the past 10 years, has led efforts to standardize Post Quantum Cryptography (PQC) to protect against quantum attacks. This paper covers a custom implementation of the open-source free5GC CN, to expand its HTTPS capabilities for VNFs by introducing PQC Key Encapsulation Methods (KEM) for TLS v1.3. This paper provides the details of this integration with a focus on the latency of different PQC KEMs in initial handshakes between VNFs, on packet size, and the implications on a 5G environment. This work also conducts a security comparison between the PQC-equipped free5GC and other open-source 5G CNs. The presented results indicate a negligible increase in UE connection setup duration and a small increase in connection setup data requirements, strongly indicating that PQC KEM’s benefits far outweigh any downsides when integrated into 5G and 6G core services.
5G Core networks are entering a decisive phase of post-quantum (PQ) migration: operators and vendors are beginning to advertise PQ-TLS 1.3, PQ-IPsec, and hybrid KEM support across the Service-Based Interface (SBI) and N2, N3, N4 reference points, in line with 3GPP TS 33.501, emerging IETF drafts, and NIST FIPS 203, 204, 205. Yet deploying PQ primitives does not guarantee PQ security. A Network Function may advertise ML-KEM-768 and silently fall back to X25519; negotiate a hybrid KEM but authenticate with ECDSA-P256; present an ML-DSA leaf on a classical chain; or skip mutual TLS altogether. These failures are silent on the wire, and today scanners (testssl.sh, sslyze, Qualys) together with 5G-specific fuzzers are PQ-unaware and telecom-blind. We present PQC Validator, a layered PQC assurance framework purpose-built for the cloud-native 5G Core, comprising a PQ Crypto Engine (L1), a PQ Conformance Prober (L2), a PQ Robustness Tester (L3), a PQ Overhead Meter (L4), and an eBPF Attestation Plane for wire-level ground truth. Its scope spans the full control-plane cryptographic surface: an independent PQ-TLS 1.3 client and server, a strongSwan-driven PQ-IPsec harness for N2/N3/N4, an eBPF/XDP/TC monitoring plane that extracts wire-level ground truth on negotiated groups and signatures, and a Kubernetes-native UI that auto-discovers NFs and emits structured PQ evidence classifying every endpoint as classical, hybrid-pq, or full-pq. A compliance suite spans TLS, PQC, 3GPP SBI, NRF OpenAPI, and security hardening, while a protocol fuzzer exercises CVE-class regressions and downgrade paths.
The rapid advancement of quantum computing presents an urgent threat to 5G networks, particularly across sensitive roaming boundaries. While existing quantum-safe solutions typically require intrusive modifications to core network functions, this paper introduces a highly crypto-agile, non-intrusive proxy architecture to secure the N32 control-plane and N9 user-plane roaming interfaces. By deliberately isolating cryptographic operations within local, containerized proxies, our design avoids complex dependency upgrades on the running 5G core. To maximize practical deployability, we developed proof-of-concept prototypes based on OpenSSL 3.5.4 offering two distinct, highly configurable variants. The first enables immediate, software-only integration utilizing Post-Quantum Cryptography (PQC) suites (ML-KEM/ML-DSA, BIKE/Falcon). The second deploys autonomous agents in a custom Pre-Shared Key (PSK) configuration fed by out-of-band Quantum Key Distribution (QKD), enabling dynamically enforced cryptoperiods and seamless Public Key Infrastructure (PKI) fallback mechanism based on real-time key availability. We evaluate this architecture using a comprehensive open-source testbed combining Open5GS and QKDNetSim. To assess practical deployability, we measured control-plane registration times, cryptographic data volume, user-plane delay, and QKD key consumption against legacy HTTP(S) baselines. Experimental results demonstrate that these quantum-safe architectures perform comparably to, or better than, legacy security. The PQC proxies maintained competitive cold-start registration times (261–285 ms), successfully balancing computational and bandwidth trade-offs. Notably, the QKD-assisted PSK configuration achieved the highest efficiency, reducing median registration time to 258.2 ms (a 4.5% improvement over legacy HTTPS) and restricting handshake data volume to 12.3 kB by bypassing heavy asymmetric certificate authentication. Furthermore, all prototypes successfully secured the traditionally unencrypted GPRS Tunnelling Protocol user plane (GTP-U) traffic traversing the N9 interface with a practically negligible delay increase ( $\sim 300~\mu $ s). Finally, the study highlights critical transport-layer constraints, such as TCP-in-TCP congestion interference, underscoring the necessity of DTLS 1.3 to optimize practical, quantum-resilient telecommunications infrastructure.
Quantum computing is reshaping the security landscape of modern telecommunications. The cryptographic foundations that secure todays 5G systems, including RSA, Elliptic Curve Cryptography (ECC), and Diffie-Hellman (DH), are all susceptible to attacks enabled by Shors algorithm. Protecting 5G networks against future quantum adversaries has therefore become an urgent engineering and research priority. In this paper we introduce QORE, a quantum-secure 5G and Beyond 5G (B5G) Core framework that provides a clear pathway for transitioning both the 5G Core Network Functions and User Equipment (UE) to Post-Quantum Cryptography (PQC). The framework uses the NIST-standardized lattice-based algorithms Module-Lattice Key Encapsulation Mechanism (ML-KEM) and Module-Lattice Digital Signature Algorithm (ML-DSA) and applies them across the 5G Service-Based Architecture (SBA). A Hybrid PQC (HPQC) configuration is also proposed, combining classical and quantum-safe primitives to maintain interoperability during migration. Experimental validation shows that ML-KEM achieves quantum security with minor performance overhead, meeting the low-latency and high-throughput requirements of carrier-grade 5G systems. The proposed roadmap aligns with ongoing 3GPP SA3 and SA5 study activities on the security and management of post-quantum networks as well as with NIST PQC standardization efforts, providing practical guidance for mitigating quantum-era risks while safeguarding long-term confidentiality and integrity of network data.
As the era of quantum computing approaches, the fundamental cryptographic primitives securing global communications face a paradigm shift. With the National Institute of Standards and Technology (NIST) finalizing new standards, the industry must urgently address the vulnerabilities of legacy systems. The imminent advent of CRQCs (Cryptographically Relevant Quantum Computers) poses an existential threat to the Public Key Infrastructure (PKI) underpinning the global digital economy. Classical algorithms such as RSA and ECC (Elliptic Curve Cryptography) are vulnerable to polynomial-time cryptanalysis via Shor’s algorithm. This study investigates the HNDL (Harvest Now, Decrypt Later) threat model and evaluates the resilience of NIST-standardized PQC (Post-Quantum Cryptography) algorithms: ML-KEM and ML-DSA. Utilizing a high-performance Fortinet networking environment, we experimentally validate that "Hybrid Mode" IPsec VPNs can achieve quantum resistance with negligible performance degradation, offering a viable migration path for enterprise infrastructure. Specifically, we benchmark the trade-offs between PQC’s larger key sizes and network latency, demonstrating that the overhead remains within acceptable operational thresholds. Implementing hybrid protocols provides a critical transition mechanism, allowing organizations to secure long-term data confidentiality against retrospective decryption while preserving interoperability with legacy systems.