An internal modem is a device installed inside a desktop or laptop computer, allowing the computer to communicate over a network with other connected computers. There are two types of internal modems: dial-up and WiFi® (wireless). The former operates over a telephone line and requires a network access phone number and logon credentials to make a connection. The latter can connect wirelessly and without credentials in certain cases. The non-qualified term “internal modem” commonly refers to the dial-up modem, as technologies that followed are used with qualifiers to differentiate them.
A current internal modem, also available as an external device, utilizes the v.92 protocol for communicating over copper telephone lines. The modem sends and receives data using modulated sound frequencies that it translates into digital bits of data. The word modem combines the words modulator and demodulator referring to this function.
External modems preceded internal models, and were in proprietary use for decades prior to 1981, which marks the release of the first affordable and practical modem for public use. The Hayes® Smartmodem® was revolutionary for its on-board controller that allowed the device to accept, store, and carry out user-generated commands. This modem could not only dial out on its own, but could also accept an incoming call from another modem. Prior to the Smartmodem, modems were designed to function either as a server or client (sender or receiver) but not both, and a phone number had to be manually dialed on the telephone base, then the receiver placed on an acoustic coupler.
The low-cost 300-baud Smartmodem operated at a speed of 300 bits per second (bps) and spawned many clones. Free bulletin board services became all the rage, quickly joined by private networking services that created graphic environments where people could point-and-click their way through proprietary content. Over the next decade as online content switched from text-based bulletin boards to fully graphic environments, the shortcomings of operating at slower speeds became clear.
Modems not only became faster, they became standard equipment, available as internal models that were soon included in every new computer. Current dial-up modems are 9600-baud, operating at a top speed of 56 kilobits (kbps) by using a combination of techniques to maximize the limitations of the technology. Server-side compression that incorporates an additional protocol known as v.44 can allow for theoretical speeds of up to 320 kbps for transferring text.
Despite steady improvement over the years, the limitations of the dial-up internal modem have given way to digital subscriber line (DSL) modems, cable modems and fiber optic modems that take advantage of newer technologies for delivering content tens to hundreds of times faster than dial-up connectivity. However, the internal modem is still standard equipment as a fallback device built into every desktop and laptop computer. For all of its antiquity, dial-up is still considered the most reliable means of online access, as telephones are commonly available even when high-speed access is not.