Modem vs. router vs. gateway explained
It’s easy to get confused when dealing with networking equipment at home. The end goal is to have a fast, consistent WiFi experience, but there are many parts that come into play toward delivering on that experience.
Often, your broadband provider's available hardware is what dictates your experience. Each available device is different and has its own purpose for networking, but it's easy to become confused from all of the available choices. Here, we break down the three most used terms—modem vs. router vs. gateway—when purchasing and managing home networking equipment.
A modem ("modulator-demodulator") is a device used to connect to the wider internet access, provided by an ISP. Your modem acts as a tunnel to carry information from your ISP’s network to your local network. It does this by connecting to the broadband company's telephone lines, optical fiber, or coaxial cabling and converts the information to a digital signal. The modem has a public IP address for your service provider to direct traffic.
Broadband providers typically lease modems to their subscribers, which can come with the added benefits of having a better managed service. While some homes opt to purchase their own modem, saving a leasing fee of about $120 a year, it's important to note that you can't buy just any modem.
Modems undergo certifications with the ability to operate on your provider's network. Be sure to check with your provider on compatible modem devices (or look for certification in device specs) before making a purchase.
For example, popular modem brand Motorola shows in this Amazon listing that the device is COMCAST certified:
The Motorola MB7621 is a high-performance modem that is certified for COMCAST service delivery. Screenshot taken from Amazon on June 28, 2020
A home router connects to the modem and acts like a traffic director on your local network. The router connects your devices via WiFi signal and Ethernet, tunneling information between them and out to the modem. There are both wireless and wired router options available.
Often, a router has a set of firewall rules to prevent malicious traffic across your devices and out to the internet. Because of the router's central position to home internet communications, it is the most common target for cybercriminals.
Now that we've explored modems and routers, let's take a look at the combination modem/router.
A gateway is a single device that can do the jobs of both a router and a modem. If you own a dual router and modem device, then it will connect your ISP’s network to your local WiFi network or Ethernet. This is often seen combined with a phone service in the same hardware device.
In the broadband industry, gateway is often colloquially used to refer to a device that is acting as a primary node (forwarding host), connecting other access points or networks. In this case, gateway may be interchangeable with a default gateway or primary router.
Which device is right for me?
Because of the capabilities of current devices and user needs, it's more than likely you'll likely need both a modem and a router or a modem/router combination.
The benefit of a modem/router combination is that it's one simple device that has inherent interoperability between the modem and router components. Gateways also support firewalls and proxy servers, allowing heightened security in the home network.
The trade off, though, is that router technology continues to evolve, opening doors to WiFi systems with great management software (residential managed WiFi). Even then, it's possible to turn off the WiFi component of your gateway device to welcome the latest WiFi system technology into your home.