Reference implementations of algorithms, for instance
cryptographic algorithms, are often the result or the input of
standardization processes. In this function they are often dedicated to the
public domain with their
source code as
public domain software. Examples are the first
CERN's httpd,
Serpent cipher,
base64 variants, and
SHA-3. The
Openwall Project maintains a list of several algorithms with their reference
source code in the public domain. A reference implementation may or may not be production quality. For example, the
Fraunhofer reference implementation of the
MP3 standard usually does not compare favorably to other common implementations, such as
LAME, in listening tests that determine sound quality. In contrast,
CPython, the reference implementation of the
Python programming language, is also the implementation most widely used in production. == Testing ==