Many Internet service providers are now giving their customers combined devices that function as both a modem and a wireless router. With these devices, you don’t have to buy a router — but you can, if you like.
While separate routers can be more powerful, configurable, and feature-filled, that isn’t necessarily a good thing for everyone. Whether you should get a separate router or not depends on what trade-offs you want to make.
Why ISPs Provide Combined Router/Modem Units
For most people, having a combined router/modem unit is just simpler. The Internet service provider can hand their customer a box and that single box handles connecting to the Internet, creating a Wi-Fi network, and sharing the Internet connection between multiple devices. Customers don’t have to buy their own router and hook it up, and the ISP doesn’t have to field support calls from confused customers who have problems setting up their routers.
Having a combined router/modem also makes some sense. Why split this functionality into two separate boxes that may have difficulty communicating with each other? This just requires more power outlets and potentially more troubleshooting — if you have a problem, you may have to troubleshoot the link between the modem and router to ensure they’re communicating properly.
ISPs also gain the ability to do other things with their modems, such as providing public Wi-Fi access to their customers via these combined modem/router units.
The main advantage to sticking with your combined modem/router unit is that it’s simpler. If you already have one, you don’t have to buy anything extra or set it up. If the unit was provided by your ISP, you can expect them to troubleshoot it for you. You won’t have to deal with problems that can occur if the devices fail to communicate properly.
How You Could Use Your Own Router
On many of these combined units, you can disable the router functionality. This will cause the modem to simply pass the connection through to the next device in line. Connect a separate router to your modem with an Ethernet cable via its LAN port and the router will get a public IP address from the modem, sending traffic back and forth and functioning as a standard router.
Even if you can’t disable the router features, you could plug your own router into the LAN port and create a separate Wi-Fi network. The router would receive a local IP from behind the combined router/modem unit, so you’d be using a local network behind another local network, which will cause problems with port-forwarding — but it should work. This isn’t ideal, but it’s definitely possible. You can often disable Wi-Fi on the combined modem/router, which will leave you with only single Wi-Fi network. There are many ways to configure these networking settings.
Why You Might Want to Get Your Own Router
The main advantage to bringing your own router is getting additional hardware and features that your ISP’s router doesn’t provide. For example, let’s say you really want the fastest 802.11ac Wi-Fi and your combined router/modem doesn’t provide it to you. You can purchase your own wireless router with the feature and connect it to your modem via Ethernet. It will then provide fast Wi-Fi access and communicate over the wired Ethernet line with your modem.
You may also want additional features your combined router/modem doesn’t provide. Perhaps you want dynamic DNS so it’s easier to access servers running on your local network from the Internet. Maybe you want quality of service (QoS) features to prioritize your network traffic. Or perhaps you’re a geek who wants to install your own custom router firmware, like OpenWrt, and turn your router into an extremely tweakable little device. OpenWrt is basically a Linux distribution with a package manager for routers, and can be used to run different types of servers and tools on your router — you can’t do this with a locked-down router/modem provided by your ISP.
So, Should You Get a Separate Router?
The decision is ultimately up to you and depends on what you want. If you’re happy with your combined router/modem unit and you don’t want any additional features it doesn’t provide, you’ll probably just want to stick with the box your ISP gave you. It’s just easier to set up and use.
On the other hand, if you want the latest wireless hardware or additional features, you can get them by purchasing your own router and connecting it to your modem. You’re trading some simplicity for more power and choice.
If you’re renting that combined router/modem from a cable Internet provider, there’s also another option — you can generally buy your own router to eliminate the router service fee from your monthly cable Internet bills. This doesn’t apply to ADSL, fiber, or satellite connections — just cable.