The End of The Cisco 5508
Cisco have recently announced the end-of-life of the Cisco 5508 wireless controller, as of August 2018. If you already have SmartNet on your product, support will continue until October 2020. After that, you’re on your own. For us as a Company, the 5508 has proved a solid and reliable product over the years, a benchmark if you like by which all other installations are measured. We’ve setup and supported many a site with these boxes and only rarely seen a problem with the hardware.
5508 Wireless Controller
What's Hot and What's Not? Cisco Controller Options
At the lower end of the spectrum sits the 2504. This has also proved a very solid unit for small sites but lacks stateful failover (SSO) and redundant power supplies. The last software release is 8.5 so although not announced, it’s highly likely that this won’t be around for long.
Move to the 3504 for small sites. It comes with SSO for sub second failover when paired with another identical unit (a dedicated rack is available for side-by-side mounting) and supports up to 150 access points. All available controller software may be loaded in line with higher end units so you don’t lose any features.
3504 Wireless Controller
To replace or match a 5508, then the 5520 is the obvious choice. It’s had a facelift and now supports up to 1500 APs (an increase of 1000) and 20000 clients, and 20Gbps throughput. If you’re an enterprise that wants MESH, Flex, central mode (local) capability and every combination then this is your man.
For high end deployments, consider the 8510 with support for 6000 APs and 64000 clients. You could go to the next controller up, the 8540, shown below:
8540 Wireless Controller
The 8540 is twice the size but offers little more than a fourfold network interface speed. While scalability is a good thing, but consider the impact when code upgrades are required and failures occur; that’s potentially a lot of upset facebook users so have fallback systems in place over and above the standard Stateful HA.
Something a Little Different?
We’ve been running a Cisco virtual wireless controller for our own office for quite a while now. In short it does what it says on the tin with all the advantages that come with virtualised technology. There are shortcomings however with the biggest being the lack of central mode operation; only Flexconnect operation is possible where traffic terminates at the edge switch.
A previous blog looked at Aruba’s Instant (IAP) solution. Cisco’s equivalent is ‘Mobility Express’ whereby the access points themselves contain their own little controller.
Alternatively one AP acts as the Master and all the other APs join it, thus reducing management to just one unit and one web GUI interface. For single office environments with no need for bells and whistles, this fits just fine.
With multiple small office locations (eg a chain of travel agents), then consider the 7510 whereby 6000 APs may be controlled over the WAN link from your head office. Since the APs are setup in Flexconnect mode, there are no WAN saturation issues since traffic stays local to the site. Should the office WAN link break, then wireless may still continue to function normally within the office space
Cisco Mobility Express Network Summary
Out With The Old
For completeness it’s worth touching on converged access.
It’s all about mobility and roaming with this approach: mobility agents, mobility controllers, mobility groups, domains and subdomains. At one point Cisco were keen to build wireless functionality into their edge switches. The edge switches (typically 3650 / 3850 ) would act as agents to a central platform (generally another 3650 or a 5760).
The central node would cache the keys of all clients in the subdomain, handle RRM and any guest access. Given that the 5760 is end of life and converged access is not supported beyond Cisco IOS XE Denali 16.3.x, we suspect that you may want to abandon this route. It never gained much ground and the reports from the field were less than positive.
The new range of 9200 / 9300 switches will be worth a look for fans of the up coming DNA Centre too - for that modern SDN fitout.