UNIVERSITI UTARA MALAYSIA
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DIGITAL MODEMS: CABLE, DSL, AND ISDN
A broadband modem, also called a digital modem, is a communications device that sends and receives data and information to and from a digital line. Three types of broadband modems:
Cable modems
DSL modems
ISDN modems.
These modems typically include built-in Wi-Fi connectivity.
A cable modem is a broadband modem that sends and receives digital data over the CATV network.
A DSL modem is a broadband modem that sends digital data and information from a computer to a DSL line and receives digital data and information from a DSL line.
Similarly, an ISDN modem is a broadband modem that sends digital data and information from a computer to an ISDN line and receives digital data and information from an ISDN line.
WIRELESS MODEMS
Some mobile users have a wireless modem that uses a mobile service provider’s network to connect to the Internet wirelessly from a computer or mobile device
WIRELESS ACCESS POINTS
A wireless access point (WAP) is a central communications device that allows computers and devices to transfer data wirelessly such as Wi-Fi.
ROUTERS
A router is a communications device that connects multiple computers or other routers together and transmits data to its correct destination on a network.
NETWORK CARDS
A network card, sometimes is a communications device that enables a computer or device that does not have built-in networking capability to access a network.
HUBS AND SWITCHES
A hub or switch is a device that provides a central point for cables in a network. Larger networks typically use a hub, while smaller networks use a switch. Some hubs and/or switches include router.
EXAMPLES
A communications device is any type of hardware capable of transmitting data, instructions, and information between a sending device and a receiving device. At the sending end, a communications device sends the data, instructions, or information from the sending device to transmission media. At the receiving end, a communications device receives the signals from the transmission media. The examples are:
Modems
Wireless access points
Routers
Network cards
Hubs and switches