Part 1: General - Computer Security Resource Center - National ...

March, 2007
Overview
The proper management of cryptographic keys is essential to the effective use of cryptography
for security. Keys are analogous to the combination of a safe. If a safe combination becomes
known to an adversary, the strongest safe provides no security against penetration. Similarly,
poor key management may easily compromise strong algorithms. Ultimately, the security of
information protected by cryptography directly depends on the strength of the keys, the
effectiveness of mechanisms and protocols associated with keys, and the protection afforded to
the keys. All keys need to be protected against modification, and secret and private keys need to
be protected against unauthorized disclosure. Key management provides the foundation for the
secure generation, storage, distribution, and destruction of keys.
Users and developers are presented with many choices in their use of cryptographic mechanisms.
Inappropriate choices may result in an illusion of security, but little or no real security for the
protocol or application. This recommendation (i.e., SP 800-57) provides background information
and establishes frameworks to support appropriate decisions when selecting and using
cryptographic mechanisms.
This recommendation does not address implementation details for cryptographic modules that
may be used to achieve the security requirements identified. These details are addressed in
[FIPS140-2] and the derived test requirements (available at http://csrc.nist.gov/cryptval/).
This recommendation is written for several different audiences and is divided into three parts.
Part 1, General, contains basic key management guidance. It is intended to advise developers
and system administrators on the "best practices" associated with key management.
Cryptographic module developers may benefit from this general guidance by obtaining a greater
understanding of the key management features that are required to support specific intended
ranges of applications. Protocol developers may identify key management characteristics
associated with specific suites of algorithms and gain a greater understanding of the security
services provided by those algorithms. System administrators may use this document to
determine which configuration settings are most appropriate for their information. Part 1 of the
recommendation:
1. Defines the security services that may be provided and key types employed in using
cryptographic mechanisms.
2. Provides background information regarding the cryptographic algorithms that use
cryptographic keying material.
3. Classifies the different types of keys and other cryptographic information according to
their functions, specifies the protection that each type of information requires and
identifies methods for providing this protection.
4. Identifies the states in which a cryptographic key may exist during its lifetime.
5. Identifies the multitude of functions involved in key management.
6. Discusses a variety of key management issues related to the keying material. Topics
discussed include key usage, cryptoperiod length, domain parameter validation, public
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