A modem is a hardware device that allows a computer to send and receive information over telephone lines. When sending a signal, the device converts digital data to an analog audio signal and transmits it over a telephone line.

A router connects devices within a network by forwarding data packets between them. This data can be sent between devices or from devices to the internet. The router does this by assigning a local IP address to each of the devices on the network. We reviewed both to take away the confusion about how they work and to help you choose which device you’ll need for your internet needs.


Decodes the signal from an ISP.
Connects directly to the internet.
Doesn’t set up a local network.
Is not responsible for Wi-Fi.


More useful in connecting LAN with the internet.
Speed depends on the cost.
Slow speed when compared to the hub.
A limited number of a system can be connected.
A modem is most probably widely used in data communication roadway.
A modem converts that the digital signal into an analog signal.
Connects to an ISP.
Compatible specifically with the ISP.
Converts the signal from the ISP to a universal one that a computer can use.


Acts just as an interface between LAN and internet.
No traffic maintenance is present.
A modem is not understood the intermediate process.
The modem does not know about the own destination path.
Can’t create a local network.
Doesn’t run Wi-Fi.
Doesn’t connect multiple devices to the internet.


Establishes a local network.
Creates and manages Wi-Fi.
Splits an internet connection to several devices.
Does not decode the signal from an ISP.
Requires a modem to connect to the internet.


It provides connection between different network architectures such as Ethernet & token ring etc.
It can choose best path across the internetwork using dynamic routing algorithms.
It can reduce network traffic by creating collision domains and also by creating broadcast domains.
It provides sophisticated routing, flow control and traffic isolation.
They are configurable which allows network manager to make policy based on routing decisions.
Creates a local area network (LAN).
Splits an internet connection to several devices.
Hosts Wi-Fi.
Runs a firewall.
Connects to a VPN.


They operate based on routable network protocols.
They are expensive compare to other network devices.
Dynamic router communications can cause additional network overhead. This results into less bandwidth for user data.
They are slower as they need to analyse data from layer-1 through layer3.
They require considerable amount of initial configurations.
They are protocol dependent devices which must understand the protocol they are forwarding.
Can’t connect directly to the internet.
Doesn’t decode the signal from an ISP.

What to Choose & When?

You need a modem and a router to set up a home network. If you’re connecting a single computer to the internet with a wire, you can use only a modem. There’s no case where you can use just a router. You’ll always need a modem to decode the signal from your ISP. When you want to speed up your network, the router is usually what you want to focus on. It has bandwidth limits, and it distributes the signal to all your devices. Your router creates and manages your Wi-Fi.

The modem usually doesn’t cause a slow connection. Generally, you’ll get one from your ISP, and they’ll give you one suitable for your subscription. If you plug in your computer directly to your modem and run a speed test, you can test whether you’re getting your advertised internet speed. If not, contact your ISP. There may be a connection issue, or your modem may be outdated. In this case, they may swap it out for a newer model.

Modem and Router Combo Devices:

There are also modems with integrated routers that perform both functions. These modems can be rented from your ISP or purchased directly. These combo devices might include a VoIP function if you have a cable, internet, and phone package. Combination devices are not usually the best option. If one part breaks, the whole thing is useless, and you can’t upgrade one device at a time. Still, if you don’t need the latest and greatest tech, buying a combo modem and router is convenient.