External Modem

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External Modem

An external modem is a peripheral device that is connected to a computer via a USB or other interface, and it provides the computer with the ability to connect to the Internet or other networks through telephone lines or cable connections. External modems are often used in situations where the computer does not have a built-in modem or where the built-in modem does not provide the desired level of performance or functionality.

What does External Modem mean?

An external modem is a device that connects a computer to a telephone line or other communication medium to facilitate data transmission and reception. It is an external, stand-alone unit that is typically connected to a computer via a serial or USB port. Unlike Internal modems that are integrated directly into the computer’s circuitry, external modems provide a convenient way to add modem capabilities to a computer, especially for devices that lack internal modem support.

External modems are equipped with a modulator-demodulator (modem) Chip that converts digital signals from the computer into analog signals suitable for transmission over telephone lines and vice versa. This allows computers to communicate with other computers or devices over phone lines, enabling remote access, internet connectivity, file transfer, and other data communication tasks.

Applications

External modems play a crucial role in technology today, providing connectivity options in various scenarios:

  • Dial-up Internet Access: Before the widespread adoption of broadband internet, external modems were primarily used for dial-up internet access. By connecting a computer to a phone line, users could establish an internet connection, albeit at relatively slow speeds compared to modern broadband technologies.
  • Remote Connectivity: External modems enable remote access to computers and networks. By dialing into a modem connected to a remote computer, users can access files, programs, and other resources as if they were physically connected to the remote system. This is particularly useful for system administration, remote troubleshooting, and accessing data from remote locations.
  • Point-of-Sale (POS) Systems: External modems are used in many point-of-sale (POS) systems to process credit and debit card transactions. These modems connect the POS system to a payment Gateway, enabling secure transmission of transaction data for authorization and processing.
  • Telemetry and Data Acquisition: External modems are employed in telemetry and data acquisition systems to transmit data over long distances. This is common in industrial settings, environmental monitoring, and remote sensing applications where data needs to be collected from sensors and sent to a central location for analysis.

History

The history of external modems can be traced back to the early days of computer networking. In the 1950s, modems were developed to connect teletype machines over telephone lines. However, it was not until the 1970s that modems became widely used for connecting personal computers.

The first external modems were bulky and slow, with transmission speeds of only a few hundred bits per second (bps). Over time, modem technology rapidly evolved, with the introduction of faster modulation techniques, digital Signal processing, and compression algorithms. This LED to significant increases in transmission speeds, reaching several megabits per second (Mbps) in the 1990s.

The advent of broadband internet technologies, such as DSL and cable modems, in the late 1990s and early 2000s, accelerated the decline of dial-up modem usage for internet access. However, external modems continue to be used in various applications, such as remote connectivity, POS systems, and data acquisition, where dial-up or cellular connections remain the primary means of communication.