At SmallNetBuilder, we're big on having shoppers understand their requirements so that they can buy a product that best suits their needs. But not everyone, especially those of us whose first interest is not home networking, wants to know the intimate details of how wireless routers work.
So if you don't want (or care) to get into the details behind what makes a wireless router tick and just want the essential information you'll need to avoid taking home the wrong router, then this article is for you.
There are now two basic types of routers:
These type abbreviations come from the IEEE 802.11 standard they are based on, i.e. 802.11g, 802.11n and 802.11ac. With the 802.11ac standard just finalized, the transition from N to AC routers will accelerate during 2014.
All AC routers are dual-band, meaning products operate in both the 2.4 and 5 GHz Wi-Fi frequency bands. You can tell if a product is dual-band if it lists 802.11a/b/g, a/b/g/n or a/b/g/n/ac in its specs.
The main variations within each router type are:
- Port Speed - WAN and LAN ports are Gigabit Ethernet (10/100/1000 Mbps) or 10/100 Mbps. Gigabit LAN ports are good to have, if you have devices with Gigabit Ethernet ports.
But you can always buy a router with 10/100 ports and pick up a 5 port Gigabit Ethernet switch later (~ $35) if you upgrade your wired network. And you have no need for a Gigabit WAN port unless your internet connection is > 100 Mbps.
- USB Ports - USB 2.0 and USB 3.0 ports can share storage and /or printers.
Don't get your hopes up on printer sharing. If it works at all, you'll find that anything other than printing on a multifunction printer won't work. And things like ink status and paper out messages probably won't make their way back to your computer.
Compatibility is better for storage sharing. But speeds are generally not equal to those on dedicated NAS (Network Attached Storage) products. And you may find that built-in media servers don't work with your players or are lacking in features you want.
There are three older product types—A, B and G—that aren't in the list above that are considered "legacy" products.
802.11a defined the original 5 GHz-only Wi-Fi products and 802.11b defined original 2.4 GHz Wi-Fi gear. 5 GHz only routers never caught on and today you find references to 802.11a only in dual-band products. B only routers were long ago replaced by G routers, which have now been pretty much replaced by N types.
G routers are still required to support B devices and N routers are required to support both B and G devices in order to be Wi-Fi Certified. AC routers are also required to support B, G and N devices. But because your shiny new router can support these older, slower device types doesn't mean that they should.
In heavy use, "legacy" devices can slow down your faster N and AC devices. You may also need to change the mode settings on your router to get certain "legacy" devices to work. So you may be better off keeping your old router and adding a new one. See How Well Do AC Routers Handle Mixed Networks? for more details.
We call sub-types of each major type classes, for lack of a better term. Class denotes the maximum link rate that the product supports. Class designations consist of the router type, plus a number indicating maximum link rate, i.e. AC1750, N300, etc.
This number is supposed to trick you into thinking that it's the actual speed that your wireless devices will run at. But it's really an indication of the technology used in the product and only good as a relative speed indicator.
Classes are defined in SmallNetBuilder's Classification System for Wi-Fi Products - Revised, with Table 1 copied below for your convenience. Note that link rate is the number reported in Windows Wireless Network Connection Status or other utilities that report wireless connection link rates.
|"Class" designation||2.4 GHz N Radio
Maximum Link Rate (Mbps)
|5 GHz AC Radio
Maximum Link Rate (Mbps)
Table 1: Wi-Fi Device classification table - routers / APs and clients
Actual real-life throughput will be at best 50% of the "N/AC number" you see in marketing material and more typically closer to 20 - 25%. This means an "N300 router" will deliver more like 60 Mbps of actual best case throughput.
The first thing you need to know is that all the numbers above 450 are sums of the maximum link rates of each radio. So each radio in an N600 router maxes out at 300 Mbps and at 450 Mbps in an N900 router. In an AC1750 router, the maximum link rate you'll see with a 2.4 GHz link is 450 Mbps or 1300 Mbps when connected on the 5 GHz band.
The next thing you need to know is that the N number is 2X the number you are likely to see reported by Windows Wireless Network Connection Status when you first connect to your new router. This is because N and AC routers support two sets of maximum link rates depending on the bandwidth mode they are operating in.
The 2.4 GHz link rates shown in Table 1 are the best case when the router is in 40 MHz bandwidth mode. The 5 GHz link rates require 40 MHz bandwidth for N routers and 80 MHz bandwidth for AC types.
The most confusing N type is 750 because each band in the router has a different top link rate and there is no way of knowing which band it is, unless you dig into the product's data sheet. And, sadly, even then, it's near impossible to tell for some products. Some products support the maximum 450 Mbps link rate on the 2.4 GHz radio, while others support it on 5 GHz.
To confuse things even further, the rates you may see reported on your Windows notebook might be lower, depending on the chipset your client device uses. Some N adapters will show only maximum link rates of 117 / 270 instead of 130 / 300 and some N150 products may only show a maximum 135 Mbps link rate. This is due to differences allowed by the 802.11 specification and it's all perfectly valid. A full list of 802.11 rates is shown below so you can have fun trying to find the "speed" number your computer is showing.
802.11n/ac MCS table
(courtesy WITS via Aerohive blog)
All AC routers support both 2.4 and 5 GHz bands and most support them concurrently. The exceptions are small travel routers with one radio that must be switched between bands.
The last thing you need to know about these link rates is that both the router and device need to support them to achieve the rates shown. If you have an N150 client connected to an N900 router, the highest link rate you're going to see reported by the device is 150 Mbps, no matter what settings you futz with on the router. How Fast Can Your Wi-Fi Go? takes you through all the combinations, so that you can see exactly what you'll get for any combination of client and router.
The rule is: The lowest link rate always wins. But just because one device operates at a less-than-maximum link rate, that doesn't mean all devices do. Routers are perfectly happy supporting each device at all the link rates it is capable of.