Wireless Glossary – C

Ratio of intended signal (carrier) to unintended signal (interference).

Optical fiber cable that has connectors installed on one or both ends. General use of these cable assemblies includes the interconnection of optical fiber cable systems and opto-electronic equipment. If connectors are attached to only one end of a cable, it is known as a pigtail. If connectors are attached to both ends, it is known as a jumper or patch cord.

The minimum recommended bending radius during installation or after installation where cable damage will not occur. Cable bend radius during installation infers that the cable is experiencing a tensile load. Free bend infers a smaller allowable bend radius since it is at a condition of minimal load. A material put on a fiber during the drawing process to protect it from the environment and handling.

Connection Admission Control is a set of measures in the network to balance between the QoSi requirements of new connections request and the current network utilisation without affecting the grade of service of existing connections.

A table within RAM which functions to store MAC addresses in a switch.

Wireless LAN media access method as specified by the IEEE 802.11 specification.

Ethernet media access method as specified by the IEEE 802.3 specification.

Category 5 cable, commonly known as Cat 5, is an unshielded twisted pair type cable designed for high signal integrity. The actual standard defines specific electrical properties of the wire, but it is most commonly known as being rated for its Ethernet capability of 100 Mbit/s.

Cat 6 – Category – 6, (ANSI/TIA/EIA-568-B.2-1) A cable standard for Gigabit Ethernet and other interconnect that is backward compatible with Category 5 cable, Cat-5e and Cat-3. Cat-6 features more stringent specifications for crosstalk and system noise. The cable standard is suitable for 10BASE-T / 100BASE-TX and 1000BASE-T (Gigabit Ethernet) connections.

The cable contains four twisted copper wire pairs, just like earlier copper cable standards, although each twisted pair is made up of slightly larger 23 gauge copper wire as apposed to Cat 5’s 24 gauge wire. When used as a patch cable, Cat-6 is normally terminated in RJ-45 electrical connectors. If components of the various cable standards are intermixed, the performance of the signal path will be limited to that of the lowest category. The distance without losing data is 220m.

Category 7 cable (CAT7), (ISO/IEC 11801:2002 category 7/class F), is a cable standard for Ultra Fast Ethernet and other interconnect technologies that can be made to be backwards compatible with traditional CAT5 and CAT6 Ethernet cable. CAT7 features even more stringent specifications for crosstalk and system noise then CAT6. To achieve this, shielding has been added for individual wire pairs and the cable as a whole. The CAT7 cable standard has been created to allow 10-gigabit Ethernet over 100 m of copper cabling. The cable contains four twisted copper wire pairs, just like the earlier standards. CAT7 can be terminated in RJ-45 compatible GG45 electrical connectors which incorporate the RJ-45 standard, and a new type of connection to enable a smoother migration to the new standard. When combined with GG-45 connectors, CAT7 cable is rated for transmission frequencies of up to 600 MHz.

Constant Amplitude Zero AutoCorrelation waveform is a periodic complex-valued signal with modulus one and out-of-phase periodic (cyclic) autocorrelation equal to zero. CAZAC sequences find application in wireless communication systems, for example in 3GPP Long Term Evolution for synchronisation of mobile phones with base stations. Zadoff–Chu sequences are well known CAZAC sequences with special properties.

Circular Buffer in which data is read in and out cyclically, so when the end of the buffer is reached the process continues at the beginning.

Cell Broadcast Centre is the part of the Core Network which manages Cell Broadcast Service messages.

Cipher Block Chaining Message Authorization Code

Cell Broadcast Entity is a source of information, external to the 3GPP system, which provides the content of a Cell Broadcast Service (CBS).

Common Control Channel is a logical channel used to deliver control information in both directions (uplink and downlink), during connection establishment.

Complimentary Code Keying

A connection type that separates signaling information from the data transmission. An example of CCS-style technology is ISDN.

Cyclic Delay Diversity is a diversity scheme used in OFDM-based telecommunication systems, transforming spatial diversity into frequency diversity avoiding intersymbol interference. CDD was introduced in 2001 and can gain frequency diversity at the receiver without changing the SISO receiver structure.

Clustered Delay Line is a type of channel model when the received signal is composed of a number of separate delayed clusters. Each cluster contains a number of multipath components with the same delay but different Angle of Departure and Angle of Arrival.

Code Division Multiplexing is a class of techniques where several channels simultaneously share the same frequency spectrum, and this spectral bandwidth is much higher than the bit rate or symbol rate.

Code Division Multiple Access is a channel access method used by various radio communication technologies. It should not be confused with the mobile phone standards called CDMAOne, CDMA2000 (the 3G evolution of cdmaOne) and WCDMA (the 3G standard used by GSM carriers), which are often referred to as simply CDMA, and use CDMA as an underlying channel access method.

A digital communication technology used by some carriers to provide PCS service. Also known as IS-95A or cdmaOne. Other technologies used are TDMA and GSM.

A member running through the center of a cable; in fiberoptic cables usually a strength member.

Control Format Indicator shows the number of Orthogonal Frequency Division Multiplexed (OFDM) symbols used for control signaling in each downlink subframe.

Carrier Frequency Offset is the difference between a reference frequency and the frequency of a received Radio Frequency (RF) carrier.

Cell Global Identification is the globally unique identity of a cell in CDMA2000 or GSM/EDGE Radio Access Network (GERAN).

Challenge Handshake Authentication Protocol is used by the Point-to-Point Protocol (PPP) to validate the identity of users.

This is used with PPP encapsulation and is a strong authentication type. It functions by hashing and sending passwords multiple times over the course of a WAN connection.

A command that the LinuxВ® operating system accepts to enable MySQLВ® and Apacheв„ў Server software for various run levels of the mysqld and httpd utilities.

Cell Identifier is an identifier of a particular cell, either a Physical CID or a Global CID. Up to 504 Physical CIDs are available.

Carrier to Interference and Noise Ratio between the power of the Radio Frequency carrier bearing the wanted signal and the total power of interfering signals and thermal noise.

A WAN connection type that includes dial-on-demand technologies like ISDN and modems.

The dielectric material surrounding the core of an optical fiber and having a lower refractive index than the core.

A more flexible way to allocate and specify Internet addresses used in routing.

An interface that names the method for communicating with an operating system. Cisco’s CLI is IOS.

This a pool of IP addresses from which the unit can assign IP addresses to clients, which perform a DHCP Request.

A VTP mode in which one is not able to delete, create, or modify VLANs. It forwards advertisements received from the server but does not save VLAN configuration to the VLAN database.

An interface configuration command that denotes the clocking speed in bps.

Connection Mobility Control comprises the processes executed by the eNodeB to manage mobility and handover in both idle and connected modes.

Module that provides power, GPS timing, and networking connections for an AP cluster. If this CMM is connected to a Backhaul Module, then this CMM is the central point of connectivity for the entire site.

Compact Modem Unit

Core Network is the central part of a telecommunication network that provides various services to customers who are connected by the access network. One of the main functions is to route telephone calls across the PSTN.

Coaxial cable is an electrical cable consisting of a round conducting wire, surrounded by an insulating spacer, surrounded by a cylindrical conducting sheath, and usually surrounded by a final insulating layer.

The cable is designed to carry a high-frequency or broadband signal, as in a high-frequency transmission line. Sometimes DC power (called bias) is added to the signal to supply the equipment at the other end, as in direct broadcast satellite receivers. Because the electromagnetic field carrying the signal exists (ideally) only in the space between the inner and outer conductors, it cannot interfere with or suffer interference from external electromagnetic fields.

The term TcodecT is also an acronym that stands for “TcoTmpression/TdecTompression.” A codec is an algorithm or specialized computer program that reduces the number of bytes consumed by large files and programs.

Coded Orthogonal Frequency Division Multiplexing is a type of OFDM scheme with a Forward Error Correction (FEC) code.

A group of nodes that share the same media and are segmented by switches. A collision happens if two nodes attempt a transmission simultaneously.

For an SM or specified group of SMs, a level of bandwidth that can be guaranteed to never fall below a specified minimum. In the Motorola Canopy implementation, for example, this is controlled by the Low Priority Uplink CIR, Low Priority Downlink CIR, High Priority Uplink CIR, and High Priority Downlink CIR parameters.

Modulation technique used by IEEE 802.11-compliant wireless LANs for transmission at 5.5 and 11Mbps.

A configuration file contains the unit configuration details. Configuration items include, among others, the IP address and other network-specific values. Configuration files may be uploaded to a TFTP server for backup and downloaded into the unit for restoring the configuration.

A 16-bit (four hexadecimal characters) value in NVRAM that describes how the router or switch should function during initialization.

An out-of-band management connection used to connect to a PC utilizing a rollover cable.

Interconnect distribution point located within the horizontal athway and space that links to the telecommunications outlet.

Core of a glass fiber. It has a higher refractive index than the cladding glass.

An arbitrary number usually based on the link’s bandwidth.

Passive component for the transmission of light between light source and fiber or between se veral fibers.

Customer Premises Equipment is any terminal and associated equipment located at a subscriber’s premises and connected with a carrier’s telecommunication channel(s) at the demarcation point (“demarc”).

Equipment located on the customer premises, this term typically refers to equipment like the router and the CSU/DSU.

Customer Premises Equipment antenna is directional antenna which points to an Access Point (Base Station)

Common Pilot Channel in UMTS and some other CDMA communications systems. In WCDMA FDD cellular systems, CPICH is a downlink channel broadcast by Node Bs with constant power and of a known bit sequence. Its power is usually between 5% and 15% of the total Node B transmit power. Commonly, the CPICH power is 10% of the typical total transmit power of 43 dBm.

Compressing a sleeve around the fiber/buffer in order to produce reliable mechanical protection.

Controlling RNC is a function an RNC can take with respect to a specific set of UTRAN access points. There is only one Controlling RNC for any UTRAN access point. The Controlling RNC has the full control of the logical resources of its UTRAN access point’s.

Cell Radio Network Temporary Identifier is a user equipment identifier allocated by a controlling RNC and it is unique within one cell controlled by the allocating CRNC. CRNTI can be reallocated when a UE accesses a new cell with the cell update procedure.

When one communications signal affects the signal in a nearby ciruit, this electrical or magnetic field is the result.

Circuit Switched FallBack, in the Evolved Packet System enables the provisioning of voice and other CS-domain services by reuse of GSM/EDGE Radio Access Network (GERAN) or UTRAN CS infrastructure when the UE is served by E-UTRAN. This function is only available if E-UTRAN coverage is overlapped by GERAN or UTRAN coverage.

Closed Subscriber Group is a set of subscribers who are permitted to access a certain cell to which access is restricted.

When there is a collision, this process sends a jam signal to notify the devices which in turn halt transmission for an arbitrary back-off time.

A device which most often provides clocking for the router, serves as a go-between for the service provider and the WAN router.

Comma Separated Variables

Cellular Text telephone Modem is a method intended for transmission of text in voice channels for the application of real time text conversation.

Clear To Send

A frame transmission method that directs its attention only on the destination MAC address of an Ethernet frame, and forwards it.

Contention Window

Maximum Contention Window Size

Minimum Contention Window Size