NTLM: Meaning (information, definition, explanation, facts)

NTLM is an authentication protocol used in a variety of Microsoft network protocols for authentication purposes.

Among others it sits on top of HTTP. It is used as a single sign-on mechanism for web browsers, so the user is able to transparently log-on to web services using his Windows credentials.

NTLM is developed by Microsoft and mostly used in Microsoft products, though others have adapted the standard, such as the Mozilla web browser and the Apache web server.

See also: Kerberos