Cisco 500 Series, Configuration Manual

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Glossary
GL-4
Cisco Security Appliance Command Line Configuration Guide
OL-12172-03
Content
Rewriting/Transfor
mation
Interprets and modifies applications so that they render correctly over a WebVPN connection.
cookie
A cookie is a object stored by a browser. Cookies contain information, such as user preferences, to
persistent storage.
CPU
Central Processing Unit. Main processor.
CRC
Cyclical Redundancy Check. Error-checking technique in which the frame recipient calculates a
remainder by dividing frame contents by a prime binary divisor and compares the calculated remainder
to a value stored in the frame by the sending node.
CRL
Certificate Revocation List. A digitally signed message that lists all of the current but revoked
certificates listed by a given
CA . This is analogous to a book of stolen charge card numbers that allow
stores to reject bad credit cards. When certificates are revoked, they are added to a CRL. When you
implement authentication using certificates, you can choose to use CRLs or not. Using CRLs lets you
easily revoke certificates before they expire, but the CRL is generally only maintained by the
CA or an
RA . If you are using CRLs and the connection to the CA or RA is not available when authentication is
requested, the authentication request will fail. See also CA , certificate , public key , RA .
CRV
Call Reference Value. Used by H.225.0 to distinguish call legs signalled between two entities.
cryptography
Encryption, authentication, integrity, keys and other services used for secure communication over
networks. See also
VPN and IPSec .
crypto map
A data structure with a unique name and sequence number that is used for configuring VPNs on the
security appliance. A crypto map selects data flows that need security processing and defines the policy
for these flows and the crypto peer that traffic needs to go to. A crypto map is applied to an interface.
Crypto maps contain the
ACL s, encryption standards, peers, and other parameters necessary to specify
security policies for VPN s using IKE and IPSec . See also VPN .
CTIQBE
Computer Telephony Interface Quick Buffer Encoding. A protocol used in IP telephony between the
Cisco CallManager and CTI
TAPI and JTAPI applications. CTIQBE is used by the TAPI/JTAPI
protocol inspection module and supports NAT , PAT , and bi-directional NAT . This enables Cisco IP
SoftPhone and other Cisco TAPI/JTAPI applications to communicate with Cisco CallManager for call
setup and voice traffic across the security appliance.
cut-through proxy
Enables the security appliance to provide faster traffic flow after user authentication. The cut-through
proxy challenges a user initially at the application layer. After the security appliance authenticates the
user, it shifts the session flow and all traffic flows directly and quickly between the source and
destination while maintaining session state information.
D
data confidentiality
Describes any method that manipulates data so that no attacker can read it. This is commonly achieved
by data encryption and
key s that are only available to the parties involved in the communication.
data integrity
Describes mechanisms that, through the use of encryption based on secret key or public key
algorithms, allow the recipient of a piece of protected data to verify that the data has not been modified
in transit.