Cisco Catalyst 9800 WLC – The Most Flexible WLC Yet


Today is the day. It’s time for the next exciting release from Cisco and this one does not disappoint. Today, Cisco introduced the Catalyst 9800 series wireless LAN controller. This WLC was introduced to be the future of Cisco wireless connectivity. There are definitely some features that will make you a believer, but there are a few things to consider before upgrading too.

Here are some of the details that I have put together around this exciting product launch:

Any Way you Want It

There are a few things with the Catalyst 9800 series WLC platform that I especially find exciting. The first thing is that this is truly a platform. This is not a single WLC that stands on its own as an appliance. There are multiple different flavors here to consider. The idea is that you can have the newest technology and have it as an option that can fit a wide array of deployment topologies. Your options for deploying a Catalyst 9800 series WLC allow you to do so in multiple locations:

  • On the Cloud
  • On a switch
  • In an on-premise appliance


Not Your Same-Old Wireless Controller

This new line of controllers is very different from the other controllers offered by Cisco currently in that it is based on the IOS-XE code. There is a huge benefit to doing this. Think of this real world example. Think of upgrades to wireless infrastructures that you have done in the past, you upgrade the WLC code and then the access points all need to share that same code, so they get upgraded as well. This can potentially be an impactful downtime window in areas such as healthcare environments. By basing the code on IOS-XE, specific modules of the code can be upgraded without impacting the entire system. This idea of hot-patching the WLC is personally a feature I am VERY excited for. But the second half of that is with the codebase on the access points themselves. Now, the access points will not always need to be upgraded just because the WLC does. They are independent and have their own patches you can apply. To accomplish these updates, the new Catalyst 9800 has a smart way to do rolling updates. You simply select the update to apply and specify the number of access points to upgrade at a time (percentage of total AP’s). Then through a process of checking neighbors through an RRM-like process, the controller can try to maintain coverage in your topology while updates take place. No longer do you have to randomize your AP upgrades to try to keep coverage with a very manual process.

Management Platforms are your Choice.

The Cisco Wireless controllers all have their standard web interface that you can use to configure and manage things. This was improved upon and expanded with Cisco Prime. The new Catalyst 9800 series line will be able to be managed with Cisco DNA Center, but that is not your only option. You can use the standard built-in web interface or Cisco Prime still. You have the option between all three platforms as to which you want to use and you can have full feature-set configurability with any of them. This is valuable for environments that want to use the new features of the new controllers without moving their environment to DNA Center yet for instance. The choice on how to manage belongs to them. This choice also applies to how you migrate to your new controller. The system you use to do so is your call as shown below:



One thing that I found interesting and useful is that you can slowly migrate to the new Catalyst 9800 series controllers if you needed to do so. If your current wireless controller such as a Cisco 5520 WLC is running at least the recently released 8.8 code, then the clients can roam seamlessly between both controllers and environments as shown below.


Usable Access Points

There is one thing to call out though as it can affect your migration to this new series of wireless controller. The access points that are supported by the new Catalyst 9800 series WLC’s are the AC wave 1 and wave 2 access points. Anything older will not be able to function with these new controllers. This was not a shocking thing to learn as some of the older access points have began to be phased out since other AireOS builds 8.X, etc. Cisco provides a matrix of compatible code levels, access points, and controllers that you will want to refer to to be 100% sure your equipment will work.

For more information

Cisco recently presented at NetworkFieldDay19 and went into some more detail about this new release. You can see the video below for yourself if you want to see what they had to share.

To find out more about this innovative new wireless controller platform from Cisco, please be sure to check out their official release documentation located here:


Catalyst 9800-40

Catalyst 9800-80

Catalyst 9800-CL

Catalyst 9300 (on switch)


  1. If positioning in the cloud – would multicast traverse the cloud infrastructure? I would hope that certain technologies like multicast do not follow the controller now that it’s being moved to the cloud. Or, is the cloud simply not a good idea if you need multicast layered your Wi-FI Topology? We’ve seen the Wi-Fi controller evolve, virtualization, etc – but I would think there remains a number of good technical reasons to not place your controller into a cloud topology.

    • I think it’s a valid concern. Cisco noted that for a cloud deployment (public) only FlexConnect with local switching is supported. This was because of bandwidth pricing in a public cloud setup. I see this case and your example together in a way. A topology could be laid out in so many different ways for so many uses, certain topologies would make more sense than others to go the public cloud route.

    • From architecture point of view it make sense to have data traffic locally switched with Flex Deployment. If customer deployment need multicast it can still be deployed with Flex Connect where server will be present locally if its a bigger site or somewhere in data-center and can traverse the smaller sites via WAN connection incase there is multicast routing configured end to end. Flex do support video streaming where multicast traffic can be converted to unicast and get optimal performance.


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