SP800108

SP 800-108 is a document published by the National Institute of Standards and Technology (NIST). Its full title is "Recommendation for Appendix F: A Security Application of the Advanced Encryption Standard (AES) Generalized Construction for Key Derivation". The primary purpose of SP 800-108 is to provide guidance on the secure derivation of cryptographic keys.

The document outlines a framework for key derivation functions (KDFs). KDFs are essential cryptographic primitives that take a secret key and some other input, such as a nonce or identifier, and generate new, related keys. These derived keys are then used for specific cryptographic operations, such as encryption or authentication.

SP 800-108 specifies a generalized construction for KDFs based on block ciphers, particularly the Advanced Encryption Standard (AES). It describes different modes of operation for these KDFs, ensuring that the derived keys are unpredictable and meet security requirements. The recommendation aims to promote interoperability and enhance the security of cryptographic systems by providing standardized methods for key derivation. It is a critical resource for developers and security professionals implementing cryptographic protocols and systems.