Broadband Modems in High-Speed Internet Networking

Cable Modem Hardware
Cable Modem Hardware. Getty Images

A broadband modem is a type of computer modem used with high-speed Internet services. The three common types of broadband modems are cable, DSL, and wireless. (Traditional computer modems, in contrast, support low-speed dial-up Internet.)  

Although the definition of broadband speed varies by country and some DSL and wireless services using older technology can fall below the official limits, they are all considered broadband modems.

Wired Broadband Modems

cable modem connects a home computer (or network of home computers) to residential cable television lines for the purpose of Internet connectivity. Standard cable modems support a version of the Data Over Cable Service Interface Specification (DOCSIS).

A DSL modem connects to residential public telephone service for Internet connectivity.

Both cable and DSL modems enable sending digital data over physical lines designed for analog communications (voice or television signals). Fiber Internet does not require the use of a modem as fiber optic cables support all-digital communications.

Wireless Broadband Modems

Wireless modem devices that connect to 3G or 4G cellular Internet services are commonly called mobile hotspots (not to be confused with Wi-Fi hotspots).  A smartphone can technically also be used as a wireless modem when connected to another local device in so-called tethering mode.

Fixed wireless broadband services may require a modem for connecting the home network to the provider's local radio equipment depending on the technology involved.

Using Broadband Modems

Like the television "set top" box, both cable and DSL modems are often supplied by the internet service provider and not a piece of equipment individuals necessarily need to shop for on their own. Broadband modems are sometimes also manufactured together with broadband routers and sold as a single unit commonly called a home gateway or residential gateway

When installed separately, a broadband modem connects to the Internet on one end and to the internal home network on the other.  The modem-to-router link can be made with either Ethernet or USB cables depending on which options each device supports  The modem-to-Internet connection is by telephone line for DSL and by coaxial cable line for cable modems.

Your Broadband Modem is Experiencing Connectivity Issues

Microsoft Windows sometimes will display this error message when troubleshooting a home broadband connection that is malfunctioning. Although the message refers specifically to the modem, this error can be raised for several different reasons:

  • set up issues or malfunctions with the broadband router
  • connection issues between the Windows computer and the router
  • malfunctions with the modem itself

Unlike routers, modems have very few settings and troubleshooting options. Administrators must normally power a modem off and then back on to reset it. For best results, both the broadband modem and router should be powered off and on together.