User Guide

614 Glossary
320657-A
CBC-MAC See CCMP.
CCI Co-channel interference. Obstruction that occurs when one signal on a particular frequency intrudes into
a cell that is using that same frequency for transmission. In multicell networks, systems are designed to
minimize CCI through appropriate transmission power and channel selection.
CCMP Counter-Mode with Cipher Block Chaining Message Authentication Code Protocol. A wireless
encryption protocol based on the Advanced Encryption Standard (AES) and defined in the IEEE 802.11i
specification. CCMP uses a symmetric key block cipher mode that provides privacy by means of counter
mode and data origin authenticity by means of cipher block chaining message authentication code
(CBC-MAC). See also 802.11i; AES; TKIP; WPA. Compare WEP.
cell The geographical area covered by a wireless transmitter.
certificate authority (CA) Network software that issues and manages security credentials and public
keys for authentication and message encryption. As part of a public-key infrastructure (PKI), which enables
secure exchanges of information over a network, a certificate authority checks with a registration authority
(RA) to verify information provided by the requestor of a digital certificate. If the registration authority
verifies the requestor’s information, the certificate authority can issue a certificate. Based on the PKI
implementation, the certificate content can include the certificate’s expiration date, the owner’s public key, the
owner’s name, and other information about the public-key owner. See also registration authority (RA).
Certificate Signing Request See CSR.
Challenge Handshake Authentication Protocol See CHAP.
CHAP Challenge Handshake Authentication Protocol. An authentication protocol that defines a three-way
handshake to authenticate a user (client). CHAP uses the MD5 hash algorithm to generate a response to a
challenge that can be checked by the authenticator. For wireless connections, CHAP is not secure and must be
protected by the cryptography in such authentication methods as the Protected Extensible Authentication
Protocol (PEAP) and Tunneled Transport Layer Security (TTLS).
client The requesting program or device in a client-server relationship. In a wireless LAN (WLAN), the
client (or supplicant) requests access to the services provided by the authenticator. See also supplicant.
co-channel interference See CCI.
collision domain A single half-duplex IEEE 802.3 Carrier Sense Multiple Access with Collision
Detection (CSMA-CD) network. A collision occurs when two or more Layer 2 devices in the network transmit
at the same time. Ethernet segments separated by a Layer 2 switch are within different collision domains.
comma-separated values file See CSV file.
communications plenum cable See plenum-rated cable.
coverage area In Nortel WMS, the smallest unit of floor space within which to plan access point
coverage for a wireless LAN (WLAN). The number of access ports required for a coverage area depends on
the type of IEEE 802.11 transmission used, and the area’s physical features and user density.
CPC Communications plenum cable. See plenum-rated cable.
CRC Cyclic redundancy check. A primitive message integrity check.