AP Design – Options, Configuration, and Security
WLAN design for an office setting can be tricky, but design is the natural, required place to start. It’s important to know which features of a particular AP are important for the environment. Of course, it’s sometimes a critical – but least capable – device that poses an issue to design for and to include in baseline requirements for that AP. It’s important to design your Wi-Fi network for the devices that will be connecting to it.
And since users can connect more than one device at a time, it’s essential to identify which device is the most important to support, whether that’s a barcode scanner, a phone, a laptop, or something else, and you are prepared for the capacity requirement for the number of clients and the equipment they are using, as well as the number of spatial streams the client has.
It’s important to know the capabilities of an AP, your client capabilities, and how well they work together. This lets you know what to look for in a data sheet for an AP and why to separate the most important and least capable client from the rest. You can’t look at the information and choose the features that are important without knowing which devices you’ll be supporting. Once that’s known, consider AP capabilities. These include:
- Supported PHY
- Frequency bands
- Number of transmit and receive spatial streams
- Ethernet speed
- Operational modes
- Guest access and security features
- PoE requirement
Use the selected AP when developing your WLAN design. Then, you’re ready to consider configuration options.
Configuration options and AP features
In a small environment, it’s possible to configure each AP individually with standalone APs. However, when rolling out more complex or larger deployments, you want centralized management using a controller or cloud management system. But not all APs support both options. If you already have a LAN architecture, you can add a wireless controller or upgrade an existing wireless controller. This makes things easier because you don’t need to alter your switching design, which is required by many cloud-managed APs.
Making the choice will require you to assess just how elaborate your current system is. We’ll now dive into operating modes, SSID overhead, access, and more as we lay out all the components that will build on your design and propel you into a manageable setup.
There are many different operating modes for APs. Some are used for access points that actively serve clients, so clients connected to the network can access network resources and be locally switched. How they operate will play into your design. Will you require passive monitoring? Point-to-multipoint?
These sorts of questions will need to be answered before you begin, and you’ll want to evaluate your current system to ensure that as your business grows, AP configuration will grow with it – in a way that’s organic and headache-free.
When thinking about APs, you have to think about the number of SSIDs that need support. Most APs support eight to 16, but the number of SSIDs adds to network overhead. Consider how each SSID and how it impacts your wireless – APs are typically configured by default to send a beacon about every 100 milliseconds, using the air every 100 milliseconds before a client even enters the environment.
Those beacons are sent out at the lowest data rate. If you have to support legacy 802.11b clients, you’ll slow down the rest of your clients with beacon traffic. This has a big impact on the client experience, plus a significant overhead expense just to add a new SSID. Limit the number of SSIDs to three or five.
Guest access and security features
Quick guest access can be set up via another SSID isolated from your regular network, putting them on a separate VLAN that has no access to the rest of the network resources. You can implement wireless client isolation so that when they are connected, they can’t send traffic to other clients connected to the same SSID. Avoid a captive portal if you can, and your end-users will experience a lot less frustration using your network. No one appreciates being stymied by a landing page that requires a password that isn’t readily available.
Another reason AP selection is so important is PoE. Every additional radio chain means a larger power requirement. How much power do your APs require? Do you have the capability in your switching infrastructure to power these devices?
When it comes to APs, it’s essential to start with design, so you don’t spend money on the wrong hardware that isn’t compatible with all devices, provides too few or too many APs, or doesn’t support the client’s spatial streams.
Access point design is worth the effort to get right the first time. Whether you’re going with on-prem or cloud management, amping up legacy hardware that needs more attention or using the latest tools, or just increasing the size of your business to something that needs more complexity, the results of good AP design will show.
7SIGNAL® is a leader in enterprise cloud Wi-Fi performance management. Founded by wireless networking pioneers, the company delivers applications that continuously monitor the stability of its clients’ Wi-Fi networks to mitigate risk. The 7SIGNAL® platform is designed for the world’s most innovative organizations, educational institutions, hospitals, and government agencies and is currently deployed at IBM, Kaiser Permanente, Nike, and other Fortune 500 companies. 7SIGNAL® continuously monitors the connectivity of an estimated 20 million global devices. Learn more at www.7signal.com.