Hi Rick, We had enabled 802.11r on our WiSM2s but had to disable it due to limitations with the PMK cache size. Cisco’s site says the 8540 has a PMK cache limit of 64,000. The site also says the WiSM2 has a limit of 30,000, but see bug CSCvg15595 because it is actually 15,000. I’m not sure if that means the limit on the 8540 is actually 64,000 or is really 32,000.
Anyway, if all of the controllers are in the same mobility group, the PMK cache limit is shared per mobility group. This may or may not be an issue depending on the size of your user base. ----------------------------------- Eric Kenny Network Architect Harvard University ITS ----------------------------------- > On Aug 28, 2018, at 3:01 PM, Phillips, Rick <[email protected]> wrote: > > We recently promoted eduroam to the primary network at the University of > Kentucky. We utilize Cisco WLC 8540’s (2 HA pairs), Cisco APs (mostly 3702’s) > and Cisco ISE for portals, authentication and authorization. We were seeing > the ISE authentication service jump up in latency and we would get calls that > users could not connect to eduroam. We have determined that our size and > number of authentications, particularly at each class change event, are such > that we should be using hardware load balancing. We are in process of setting > that up but each class transition results in a short period where > authentication latency can get to be a problem and users have a less than > desirable experience. During the time we are building this out our engineers > are wanting to enable 802.11R (Fast Transition) on our controllers. We > currently do not support this feature on the WLCs. We are running 8.2.166.0 > code on our WLCs and we have heard other have issues with this code release. > While we are not experiencing the same results or hitting the same bugs, I am > concerned that turning on this feature might have ramifications related to > the code release we are running. > > My question to the group is who has used 802.11R and would you be willing to > shoot me a private message with configuration and/or your results? > > Thanks in advance, > > Rick > > Rick Phillips > Executive Director, Networking & Infrastructure > > Information Technology Services > University of Kentucky > 301 Rose St. Hardymon Building Rm 102 > Lexington, KY 40506-0496 > (859) 257-4106 (Office) > > > ********** Participation and subscription information for this EDUCAUSE > Constituent Group discussion list can be found at > http://www.educause.edu/discuss. ********** Participation and subscription information for this EDUCAUSE Constituent Group discussion list can be found at http://www.educause.edu/discuss.
