Despite the importance of a good modem when setting up a network, there are only a few major concerns you need to look at when picking the right device for your system. Consider the different types available and pick one that is right for the type of Internet signal you have, and also be sure that it is compatible with your particular ISP.
Look at the interface connection used by each modem to ensure you pick one that works with your computer or other hardware, and consider any additional features you need. The transmission rate is the most important technical feature when looking at modems, as it directly impacts how quickly you can send and receive data, so be sure to pick the fastest option you can.
Types of Modems
Dial-Up Modem
These are older devices used to connect to the Internet over a telephone line. Unless you are in a very rare and specific circumstance where you only have access to dial-up Internet, there is no reason to choose this type of modem.
Used to connect to a cable Internet service, this is one of the fastest options on the market. If you have cable Internet, then this is the modem to choose. Be sure to pick one that is fast enough and compatible with your specific ISP.
DSL Modem
Digital Subscriber Line, or DSL, uses traditional telephone lines to deliver high-speed Internet access. If you have a DSL signal, then choose this type of modem, but be sure that it works with your ISP.
Satellite Modem
A satellite modem receives a wireless Internet signal from a satellite, providing you with a connection just about anywhere. These are specialty devices that are typically used to provide internet connections to remote areas that are not served by traditional cable or DSL.
In-Car Modem
This is another specialty item that turns your vehicle into an Internet hotspot. While many modern mobile phones can act as wireless hotspots, using one in a moving vehicle can be difficult as you transfer from one signal area to the next. In-car modems ensure consistent coverage and signal strength no matter where you go.
Gateway Modem
A gateway modem receives and sends signals along the Internet just like other modems, but also creates a Local Area Network (LAN). This is typically used in a residential household or small office if you want to connect to the Internet and create a small local network all with a single device. If you plan on using a separate router, then you do not need a gateway modem.
Interface
The interface refers to the connections available on a modem, which you then use to connect a router, computer, or other hardware to it. Most modems have one input connection that you use to connect to the source of your Internet signal, either a phone line or cable input. From there, you get at least one interface output connection, which you use to connect your modem to other hardware. This is usually an Ethernet or Cat-5 cable that connects to a port on your router, computer, or other device.
Some models can include a PCI or PCIe connection or even a USB port for connecting other devices. Choose a modem based on the connections you have on your computer or router to make sure you can easily plug your modem into your other hardware.
Maximum Data Rate
The data rate indicates the speed at which data is received and sent by the modem. This is important because the actual rate is determined by your ISP, based on the data rates they set, but your modem can bottleneck performance. If your modem only supports speeds that are slower than what your ISP provides, then you won’t be able to take advantage of the fast Internet you pay for.
You want to look at both upstream and downstream rates. Upstream indicates how fast you can send data, while downstream shows how fast you can receive it. Downstream (or received rate) is usually much faster than upstream.
ISP Compatibility
This can be easy to overlook, but it is very important to make sure that you choose a modem that is compatible with your ISP. Make sure you know what type of Internet you have - usually either cable or DSL - as well as the name of your ISP.
With that in mind, look at any modem you might be interested in and make sure it specifically works with your ISP, whether you have Cox, Time Warner, or another company. If you really want to be sure, contact your ISP and ask them if the specific modem model you plan on using is compatible with their service.
Additional Networking Features
While compatibility and data rates might be your biggest priority, there are some extra features that you should consider. Look for security and encryption features as you compare different modems, though mostly you want to be sure that any network security you plan on using will work with your chosen modem.
If you don’t already have a wireless router, then consider a gateway modem that provides you with a local wireless network as well as connecting to your Internet service. Finally, look for models that include some future-proofing thanks to support for the latest standards such as IPv6.
Manufacturer and Warranty
While the names of manufacturers of modems might not be familiar in every household the way that computer builders are, it’s still important to choose a company that provides reliable hardware in their builds. Manufacturers like D-Link, Netgear, and ARRIS produce good modems that work well and run nice and fast. While you can usually rent a modem from your ISP, buying one typically saves you money in the long run, but only if it lasts you a few years. A one-year warranty is the bare minimum you should look for, while two or three-year warranties are preferable.