RFC 9909 - Internet X.509 Public Key Infrastructure -- Algorithm Identifiers for the Stateless Hash-Based Digital Signature Algorithm (SLH-DSA)

• Status: Proposed Standard
• Published: December 2025
• Stream: IETF
• Errata: RFC Editor Errata

Abstract

This document specifies conventions and algorithm identifiers for using SLH-DSA in the X.509 Public Key Infrastructure, including signatures, subject public keys, private keys, ASN.1 modules, and examples.

Contents

• 1. Introduction
• 2. Conventions
• 3. Algorithm Identifiers
• 4. SLH-DSA Signatures
• 5. Subject Public Key Fields
• 6. Key Usage Bits
• 7. Private Key Format
• 8. Operational Considerations
• 9. Security Considerations
• 10. IANA Considerations
• 11. References
• Appendix A. ASN.1 Module
• Appendix B. Security Strengths
• Appendix C. Examples
• Acknowledgments
• Authors' Addresses

Related Resources

• Official Text: RFC 9909
• Official Page: RFC 9909 DataTracker
• Errata: RFC Editor Errata