ctions to long-distance providers that bypassed local telephone companies. CAPs are now often referred to as Competitive Local Exchange Carriers (CLECs) or competitive providers. CCIS (Common Channel Interoffice Signaling) A signaling technique used in public networks. Signals such as those for dial tone and ringing are carried on a separate path from the actual telephone call. CCIS allows for telephone company database queries used in features such as caller ID, call forwarding, and network-based voicemail. CCIS channels are also used for billing and diagnosing public network services. CDMA (Code-Division Multiple Access) An air interface used to transmit digital cellular signals between handheld devices and cellular carriers' networks. CDMA assigns a unique code to every voice and data transmission by using a channel of a particular carrier's airwaves. CDMA is a spread-spectrum technology that is used by Verizon Wireless, Sprint, and South Korean carriers such as SKT. CDMA2000 (Code-Division Multiple Access 2000) A 3G technology for carrying high-speed data and multimedia traffic on cellular networks. CDMA2000 1X (Code-Division Multiple Access 2000) The earliest version of the CDMA2000 3G technology for carrying high-speed data and multimedia traffic on www.TechnicalPDF.com cellular networks. CDMA2000 1xEV-DO (Code-Division Multiple Access 2000 Data Optimized or Data Only) A later, higher-data-rate version of CDMA2000 1X 3G technology for carrying high-speed data and multimedia traffic on cellular networks. central office The site in the Public Switched Telephone Network with the local telephone company's equipment that routes calls to and from customers. It also has equipment that connects customers to Internet service providers and long-distance services. channel A path for analog or digital transmission signals. With services such as ISDN, T1, and T3, multiple channels share the same one or two pairs of wires or fiber. CIC (Carrier Identification Code) The four-digit code (previously three digits) assigned t