A cable modem is a device that enables you to hook up your PC to a local cable TV line and receive data at about 1.5 Mbps.

CDMA (Code-Division Multiple Access) is a form of multiplexing, which allows numerous signals to occupy a single transmission channel, optimizing the use of available bandwidth. The technology is used in ultra-high-frequency (UHF) cellular telephone systems in the 800-MHz and 1.9-GHz bands.

CHAP (Challenge Handshake Authentication Protocol) is a type of authentication in which the authentication agent (typically a network server) sends the client program a random value that is used only once and an ID value.

By transmitting only the hash, the secret can't be reverse-engineered. The ID value is increased with each CHAP dialogue to protect against replay attacks

A type of communications in which a dedicated channel (or circuit) is established for the duration of a transmission. The most ubiquitous circuit-switching network is the telephone system, which links together wire segments to create a single unbroken line for each telephone call.

Client/server describes the relationship between two computer programs in which one program, the client, makes a service request from another program, the server, which fulfills the request. Although the client/server idea can be used by programs within a single computer, it is a more important idea in a network

For example, to check your bank account from your computer, a client program in your computer forwards your request to a server program at the bank. That program may in turn forward the request to its own client program that sends a request to a database server at another bank computer to retrieve your account balance. The balance is returned back to the bank data client, which in turn serves it back to the client in your personal computer, which displays the information for you.

The clock signals are only used for synchronous communications. The modem or DSU extracts the clock from the data stream and provides a steady clock signal to the DTE. Note that the transmit and receive clock signals do not have to be the same, or even at the same baud rate.

The term console port usually refers to a connector attached to network equipments for the purpose of management. You will find the console port labeled "COM", "AUX" or "Console", at the back panel of network equipments such as Desktop PC's or laptop computer, servers, modems, switches, power controls, UPS, air conditioners, PBX systems. Console port is the only universal management media to manage the network/Telco equipment.

All UNIX servers running on RISC platforms use console port for monitoring and management. Console port also provides access to low-level system configuration (BIOS "monitor mode," even before the OS is loaded) and remote power-on/off through the serial console.