External Modem


An external modem is a standalone device, separate from a computer, that enables communication between the computer and a network. It connects to the computer via a cable, often through serial, USB, or Ethernet ports. The modem converts the digital signals from a computer into analog signals for transmission over telephone or cable lines and does the reverse for incoming signals.


The phonetics of the keyword “External Modem” is: eks-tur-nuh-l moh-duhm

Key Takeaways

Below are the three main takeaways about an external modem.“`html

  1. Connection Flexibility: External modems can be easily connected and disconnected from the computer. They usually connect through a serial port or USB, offering flexibility for users to use the modem with different computers.
  2. Less Prone to Overheating: Unlike internal modems, external modems have their own casing which offers better heat dissipation. This makes it less likely for them to overheat, prolonging their lifespan.
  3. Easy Troubleshooting: Because external modems are separate from the computer system, they are easier to troubleshoot. Users can reset, power-cycle or visually inspect the modem for any issues like indicator light status.



The term “External Modem” is critical in the field of technology as it refers to a key device that enables computer systems to communicate and connect over a network. Unlike an internal modem that is embedded within the computer system, an external modem is a standalone device which connects to a computer through a wired connection, commonly a USB or an Ethernet cable. It plays a vital role in transmitting digital data over communication lines such as phone or cable lines by modulating the digital signal into analog and demodulating the analog signal back into digital form. As it is external, it ensures easier troubleshooting, replacement, and offers flexibility of use across multiple systems, thereby maintaining the robustness and efficiency in network communications.


An external modem is a device that enables a computer to communicate with other systems over a network, such as the internet, via a connected phone line. It’s designed to modulate an analog carrier signal to encode digital information, and also demodulate such a carrier signal to decode the transmitted information. It’s a critical piece of equipment for dial-up connections and is generally connected to a computer through an RS-232 interface, a USB port, or a serial port.In practice, the primary purpose of an external modem is to offer connectivity. With the aid of this technology, a computing system can communicate and transfer data with other systems through established networks or direct dial-up connections. External modems are commonly used to provide internet access, allowing the user to send and receive emails, browse websites, download files, and perform other online activities. Even as broadband connections become more common, external modems are still invaluable in areas with limited network infrastructure or where other forms of connectivity are not readily available.


1. Zoom 5363 AC1900 Cable Modem/Router: This is a two-in-one device which includes an external modem and a wireless router. It acts as a bridge between an Internet Service Provider (ISP) and devices in a home or an office, allowing them to connect to the internet.2. NETGEAR CM500 High Speed Cable Modem: This is an external modem which facilitates high-speed internet connectivity through a direct Ethernet connection to a computer or wireless router. It’s well suited for plans up to 300 Mbps.3. ARRIS SURFboard SBG7580AC 32×8 DOCSIS 3.0 Cable Modem: This is a high-speed external modem with Wi-Fi router. It supports internet plans up to 1.4 Gbps download and 345 Mbps upload speed. It also includes 4 Gigabit Ethernet ports for wired connections.

Frequently Asked Questions(FAQ)

Q: What is an external modem?A: An external modem is a communication device used to connect computers and other devices to the internet. It is located outside the main computer system or device and is connected via a cable.Q: How does an external modem work?A: The external modem works by converting digital signals from your computer into analog signals that can travel over telephone or cable lines. Upon receiving, it reconverts the signal back to digital format.Q: What are the advantages of using an external modem?A: External modems are easier to install and troubleshoot since they are externally placed. They also do not consume the computer’s resources, hence improving the overall performance of the system.Q: What are the different types of external modems?A: The different types of external modems include dial-up modems, cable modems, DSL modems, and fiber-optic modems.Q: How can I connect an external modem to my PC?A: External modems often connect to a computer’s serial or USB port and require a simple physical installation. It’s crucial to install the corresponding software drivers too.Q: What’s the difference between an external modem and an internal modem?A: The main difference is that an internal modem is installed inside the computer, typically a PCI or PCIe slot, while an external modem is connected to the computer externally, usually through a serial or USB port.Q: Is the speed of internet connectivity dependent on the external modem?A: Yes, the speed of your internet can be significantly impacted by the type and quality of the modem you use. For instance, fiber-optic modems generally offer faster speeds than dial-up or DSL modems.Q: Can I use an external modem for my laptop?A: Of course, just as long as your laptop has the appropriate port (such as a USB port) to connect the modem.Q: What should I do if my external modem is not working?A: First, ensure that all connections are secure and the device is powered on. If the issue persists, restart your modem or reset it to factory settings. If all else fails, contacting your service provider or a tech support center can provide further assistance.Q: Do I need a separate router with an external modem?A: A separate router is not necessary if your modem has built-in router functions. However, if it doesn’t, you’ll need a separate router to distribute internet connection to multiple devices.

Related Finance Terms

  • Dial-Up Connection
  • Internet Service Provider (ISP)
  • Serial Port
  • Data Transmission
  • Network Infrastructure

Sources for More Information


About The Authors

The DevX Technology Glossary is reviewed by technology experts and writers from our community. Terms and definitions continue to go under updates to stay relevant and up-to-date. These experts help us maintain the almost 10,000+ technology terms on DevX. Our reviewers have a strong technical background in software development, engineering, and startup businesses. They are experts with real-world experience working in the tech industry and academia.

See our full expert review panel.

These experts include:


About Our Editorial Process

At DevX, we’re dedicated to tech entrepreneurship. Our team closely follows industry shifts, new products, AI breakthroughs, technology trends, and funding announcements. Articles undergo thorough editing to ensure accuracy and clarity, reflecting DevX’s style and supporting entrepreneurs in the tech sphere.

See our full editorial policy.

More Technology Terms

Technology Glossary

Table of Contents