Algorithmic diversity for quantum-safe key exchange. A code-based Key Encapsulation Mechanism selected by NIST in 2025, providing security from fundamentally different mathematical assumptions than lattice-based schemes — essential insurance for defense-in-depth strategies.
Code-based cryptography provides a fundamentally different security foundation from lattice-based ML-KEM. Deploy alongside ML-KEM for true cryptographic diversity — a key requirement of defense-in-depth strategies.
Security is based on the hardness of decoding random quasi-cyclic codes — a well-studied problem with decades of cryptanalytic research. Independent of lattice assumptions.
Area-optimized hardware architecture leveraging the mathematical structure of quasi-cyclic codes. Suitable for embedded and resource-constrained deployments where silicon budget is critical.
The HQC Code-Based KEM Engine implements the Hamming Quasi-Cyclic Key Encapsulation Mechanism, selected by NIST in March 2025 for post-quantum standardization. HQC's security rests on the hardness of decoding random quasi-cyclic codes — a fundamentally different mathematical problem from the lattice problems underlying ML-KEM, providing critical algorithmic diversity.
The hardware architecture features optimized polynomial multiplication engines that exploit the quasi-cyclic structure of HQC, along with dedicated error-correction decoders that recover shared secrets from noisy ciphertext during decapsulation. This purpose-built silicon approach delivers consistent performance with constant-time execution guarantees.
Organizations adopting a belt-and-suspenders approach to post-quantum migration can deploy HQC alongside ML-KEM in a hybrid configuration. If a breakthrough were to compromise lattice-based schemes, the code-based HQC component maintains quantum-safe key exchange. This diversity strategy aligns with ANSSI, BSI, and CNSA 2.0 recommendations.
| Parameter | Value |
|---|---|
| Algorithm | HQC (NIST Selected 2025) |
| Type | Code-Based KEM |
| Security Basis | Quasi-cyclic code decoding |
| Shared Secret | 32 bytes |
| Security Levels | 128 / 192 / 256 bit |
| Interface | Standard bus interface |
| Target Clock | 80 MHz |
| Parameter | HQC-128 | HQC-192 | HQC-256 |
|---|---|---|---|
| Security Level | 128-bit | 192-bit | 256-bit |
| Public Key Size | 2,249 bytes | 4,522 bytes | 7,245 bytes |
| Ciphertext Size | 4,497 bytes | 9,042 bytes | 14,485 bytes |
| Shared Secret | 32 bytes | 32 bytes | 32 bytes |
| Parameter | Value |
|---|---|
| Interface | Standard register-mapped bus interface |
| Data Width | 32 bits |
| Target Clock Frequency | 80 MHz |
| Key Generation Latency | ~1.5 ms @ 80 MHz (HQC-128) |
| Encapsulation Latency | ~2.0 ms @ 80 MHz (HQC-128) |
| Decapsulation Latency | ~2.5 ms @ 80 MHz (HQC-128) |
| Verification | NIST Known Answer Test vectors |
| Attribute | ML-KEM-768 | HQC-128 |
|---|---|---|
| Security Basis | Lattice problems | Code decoding problems |
| Public Key Size | 1,184 bytes | 2,249 bytes |
| Ciphertext Size | 1,088 bytes | 4,497 bytes |
| Operation Latency | ~0.3–0.4 ms | ~1.5–2.5 ms |
| Primary Advantage | Smaller sizes, faster | Algorithmic diversity |
HQC is purpose-built for organizations that require algorithmic diversity as a core security principle. By deploying code-based HQC alongside lattice-based ML-KEM, systems remain protected even if a mathematical breakthrough compromises one algorithm family. This hybrid strategy is recommended by leading national cybersecurity agencies for the most sensitive applications.
Choose the integration level that matches your design requirements.
Complete source with verification suite, driver library, and documentation. Includes hybrid configuration scripts for combined ML-KEM + HQC deployments. Maximum flexibility for any target technology.
Optimized for target technology with timing models and physical abstractions. Pre-characterized for 80 MHz operation at 1.8V nominal.
Fully validated physical implementation with complete signoff documentation. Available standalone or as a combined ML-KEM + HQC hybrid macro.
KEM and security cores for comprehensive quantum-safe deployments.
Contact our team for evaluation access, hybrid deployment guidance, or custom integration support for your code-based KEM requirements.