User guide

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Glossary
Certificate Authority (CA)—An online system that issues, distributes, and
maintains currency information about digital certificates. Abbreviated as CA.
Certificate policy—A statement that governs the use of digital certificates.
Certificate revocation—The act of invalidating a digital certificate.
Certificate revocation list (CRL)—A list generated by a CA that enumerates digital
certificates that are no longer valid and the reason they are no longer valid.
Certificate suspension—The act of temporarily invalidating a certificate while its
validity is being verified.
Challenge Handshake Authentication Protocol (CHAP)—A session-based two-way
password authentication scheme. Widely used authentication method in which a
hashed version of a user’s password is transmitted during the authentication
process (instead of passing the password itself). Using CHAP, a remote access
device transmits a challenge string, to which the client responds with a message
digest (MD5) hash based on the challenge string and the users’ password. Upon
receipt, the remote access repeats the same calculation and compares the value
sent to that value; if the values match, the client credentials are deemed authentic.
Cipher—A method of encrypting text. The term is also used to refer to an
encrypted message (although the term cipher text is preferred). Any cryptographic
system in which arbitrary symbols or groups of symbols represent units of plaintext
or in which units of plaintext are rearranged, or both.
Clear text—Characters in a human-readable form or bits on a machine-readable
form. Also called plaintext.
COMSEC—Communications security.
Compliance—In a UAC network, compliance means that the user and endpoint
computer meet network authentication and security requirements and are,
therefore, allowed to access protected resources on the network.
Cookie—A file or token of sorts passed from the Web server to the Web client (your
browser) that is used to identify you and could record personal information such as
ID and password, mailing address, credit card number, and so on. Also called HTTP
cookie.
Credentials—Information passed from one entity to another and used to establish
the sending entity’s access rights—commonly a user name and a password.
Cross certification—When two or more Certificate Authorities choose to trust one
another and issue credentials on each other’s behalf.
Cryptographic module—Any combination of hardware, firmware, or software that
implements cryptographic functions such as encryption, decryption, digital
signatures, authentication techniques, and random number generation.