Choosing the Right Tool for Your WLAN

By scottm32768 posted 01-20-2020 03:35 PM


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There are many different kinds of shovels and many different kinds of rakes. However, not all shovels or rakes are equally suited for a particular task. In the same way, not every AP meets the business requirements for every WLAN. That's why Aruba Instant-On provides a number of options for AP models. This allows the network to be designed with the right AP to meet those requirements. All designs need to start with requirements and those requirements are based on your devices and their capabilities.

For example, if you have a network full of the latest and greatest laptops, they probably have a very capable WLAN radio with support for 3x3 MIMO. This means you'll need a 3x3 or 4x4 AP to maximize your throughput if maximum throughput is a requirement for your network. Don't forget that higher-end APs with more MIMO capability aren't just about throughput. Wi-Fi is a shared medium and all clients are sharing the same channels. If clients can get on the channel, talk very quickly, then get off the channel, that leaves more capacity for additional clients.

Now, you might be thinking, "All my Wi-Fi traffic goes to the Internet and that connection is much slower than Wi-Fi, therefore the slower gear will be more than sufficient." That line of thinking may be sound, but there are a couple of reasons you might want to use faster gear even if that at first appears to exceed your business requirements.

How long will you leave these APs deployed?

Many businesses install APs and expect them to last for five to seven years or even longer. Manufacturers are supporting and selling them longer, as evidenced by this table in the Airheads Community.

How fast will your Internet backhaul be in five years? Nielsen's Law of Internet Bandwidth says bandwidth grows by 50% per year. The APs might end up becoming the bottleneck.

What about the devices that will be connecting to it? A few years ago, smartphones were 1x1 devices, many of which were still using 802.11n (or Wi-Fi 4 in modern marketing terms). Now the flagship devices are 802.11ax (Wi-Fi 6) and are using 2x2 or better radios. There are also more devices for each person. It's not uncommon to see a person with a minimum of two devices on them at all times because so many people now have a smart watch in addition to their phone, let alone a computer or tablet.

Using more capable APs will cost a little more now, but it may be an investment that buys the additional performance and capacity that saves you from replacing them earlier than planned.

Where will these APs be deployed?

Are the APs being deployed in an area that already has a high density of Wi-Fi? Can you see dozens of networks around you? Remember I said that Wi-Fi is a shared medium? Only one station (that's an AP or a client device) can talk on a Wi-Fi channel at a time. If you have your AP on 5GHz channel 36 and 12 other networks also have APs on channel 36, all of you have to take turns using the channel. This means that if your devices can talk to the AP faster, you'll see better performance in that challenging environment than you would if the AP was less capable.

AP model choices

There are a handful of models to choose from in Aruba Instant-On. The AP11, AP12, and AP15 are progressively more capable standard ceiling-mounted APs. These will likely be your workhorses. The AP11D is a favorite of mine because it can mount on a wall plate or sit on a desk and has Ethernet ports if you want to connect some wired devices. The AP17 isn't one I've had the chance to try out, yet. It's the outdoor model and would be great for covering walkways, parking lots, or even the yard around a home.

All the AP models are inexpensive and there's a range of performance options to choose from and several form factors. This gives you the flexibility to design a high-quality WLAN that meets the requirements for the deployment without breaking the bank.

About the Author

Scott McDermott is an enterprise network engineer and blogger with more than 20 years in IT and a background in multiplatform system administration. He wears lots of hats, but is particularly fond of wireless networking and network design. He enjoys a good packet capture, mentoring others and passing certification exams.