CALEA
Communications Assistance to Law Enforcement Act
A 1994 law granting law enforcement agencies the ability to wiretap new digital networks and requiring wireless and wire line carriers to enable eavesdropping equipment use in digital networks.

Caller ID
An enhanced feature that displays a caller's phone number on the wireless handset.

Calling party pays
This service bills the originator of a call to a wireless device rather than the receiver and is more common in other countries than in the United States. However, many US carriers are pushing for calling party pays, since it would probably increase minutes of use.

Cap code
A pager's unique electronic identification number on the back of the device

Carrier Current LAN
A LAN that uses power lines as a medium for the transport of data

Category 1
twisted pair wire
Old type telephone wire before 1983 not very good for data transmission

Category 2
twisted pair wire
Good for data rates up to 4 Mbps with IEEE 802.5 token rings

Category 3
twisted pair wire
good up to 10 Mbps with IEEE802.3 10Base-T

Category 4
twisted pair wire
good up to 16 Mbps with IEEE 802.5

Category 5
twisted pair wire
good up to 100 Mbps if properly untwisted

CDDI
copper data distributed interface
Version of FDDI specifying the use of unshielded twisted pair wiring

CDPD
Cellular Digital Packet DATA
Overlays analog cellular telephone system using channel hopping technique to transmit data in short bursts, full duplex in 800 and 900 MHz band good up to 19.2 kbps

CDMA
code division multiple access A spread spectrum air interface technology used in some digital cellular, personal communications services and other wireless networks.

cdma2000
A third-generation wireless technology proposal submitted to the International Telecommunication Union, which is based on the IS-95, or cdmaOne, standard.

cdmaOne
The IS-95 CDMA standard developed by Qualcomm Inc.; a word coined by the CDMA Development Group.

Cell site
The location where the wireless antenna and network communications equipment is placed.

Cellemetry
Brand name for Cellemetry LLC's telemetry service, which uses the cellular network to carry data messaging used for remote services such as utility meter reading, vending machine status and vehicle or trailer tracking.

Centronics
Standard 36 pin parallel 200Kbps asynchronous interface for printers and other devices

Charge back
The funds a carrier will "charge back" to an agent or dealer if a customer discontinues service shortly after buying the product.

Churn
A measure of the number of subscribers who leave or switch to another carrier's service.

ClassLink
A program of the CTIA Foundation providing wireless phones to schools for teacher use and student Internet access.

CLEC
competitive local exchange carrier
A new entrant providing local wireline phone service.

Clear channel
assessment
Function to determine the state of wireless medium in IEEE 802.11

Click-box bidding
A method of bidding for FCC spectrum licenses in which the participant does not enter a bid amount but simply clicks on the computer screen to enter an amount shown.
The method was first introduced in the auction of upper channel 800 MHz licenses in the fall of 1997.

CMRS
commercial mobile radio service
An FCC designation for any carrier or licensee whose wireless network is connected to the public switched telephone network and/or is operated for profit.

Components
Semiconductors and smaller elements used in handsets and infrastructure equipment.

Coaxial cable
solid metal core with shielding as a return path for current flow.
Better than twisted wire less noise interference within the core wire

Content services
Paging service, beyond telephone number alerts, that include news and sports headlines, personalized stock quotes, driving directions, restaurant reviews.

Control channel
A logic channel carrying network information rather than the actual voice or data messages transmitted over the network.

Cost Recovery
Reimbursement to CMRS providers of both recurring and nonrecurring costs associated with any services, operation, administration or maintenance of wireless E911 service.
Costs include, but are not limited to, the costs of design, development, upgrades, equipment, software and other expenses associated with the implementation of wireless E911 service.

Covered SMR
       A subset of specialized mobile radio operators subject to a particular set of regulations.
       A definition developed in December 1997 during the implementation of E911 regulations encompasses operators whose networks use intelligent switching capabilities and offer seamless hand-off to customers.
       An earlier, broader definition, still applicable in other contexts, encompasses operators that provided two-way, real-time voice services across geographic license areas in the 800 MHz and 900 MHz bands.

CPE
consumer premise equipment Telephones, PBXs and other communications devices located in the home or office.

CPNI
      customer proprietary network information.
       The carrier's data about a specific customer's service and usage.
       The FCC restricts CPNI use in marketing, banning win-back efforts specifically aimed at high-usage customers who have quit a network.

CRC
Cyclic Redundancy Check
Error detection process that divides the data being send by a polynomial and appends the resulting remainder to the transited data

CTIA
Cellular Telecommunications Industry Association.
A trade group representing cellular, PCS and enhanced specialized mobile radio carriers.