NIST SP 800-61
NIST SP 800-61r1
NIST SP 800-94
A host-based intrusion detection and prevention program that monitors and analyzes activity and may also perform prevention actions.
NIST SP 800-95
A program acting on behalf of a person or organization. (Web Services Glossary - W3C Working Group Note 11 February 2004, http://www.w3.org/TR/2004/NOTE-ws-gloss-20040211)