Re: [WIRELESS-LAN] Wireless and Apple Clients

[Rick Brown]

While this isn't the most elegant of solutions; perhaps this situation is much like in years past where the lower data rates were turned off in order to improve roaming, would it be possible to disable some of the lower data rates on the 5Ghz range and possibly help with the client choosing 2.4GHz over 5GHz.  I don't know what your transmit power is but remember that just because a client can hear an AP that doesn't mean the AP can effectively hear the client, especially in the types of building you are dealing with.  While the band steering and Aruba issues may be valid, it seems that band steering of any flavor would only work efficiently if there were no coverage holes in either frequency band.  Just some random musings this morning! Rick Mark H. Wehrle wrote: Hi all,   I want to check in to see if others are experiencing the same things that we’re seeing here at Penn regarding Apple clients’ connectivity and wireless issues on campus. I realize that some of you operate wireless with different vendor equipment, but we’re trying to debug this problem with our vendors (Aruba and Apple) so I’d like to hear what you are up against for a comparison or benchmark.   Here’s what we’re facing:   We run Aruba AP125’s with N+1  controller architecture. We have 802.11N enabled (since July) and running it at both 2.4Ghz and 5Ghz in some campus buildings. Wireless coverage was planned/designed for B/G (2.4) and  5Ghz is best effort but still pretty good in some areas. OS is 3.4.2.4 and we have band steering enabled. Problem is that in some areas (our Quadrangle complex which is a group of connected buildings in Resnet) and various Macs (mostly) running OS 10.6 (and other OS’s) will favor the 5Ghz radios even though a better signal on 2.4 is available. We’ve had a Windows machine right next to an Apple client in a troubled area and the Windows machine connects fine. Apple will not connect (or barley connect). Aruba is working with us on to debug this. First reports back from them are that band steering works best in highly dense 5Ghz-covered buildings (which we don’t have). The location that I’m referring to is over 100 years old so coverage is rough due to building materials and layout but thus far 2.4Ghz coverage has been OK for most devices (though we have some dead spots which get AP’s installed as needed). Aruba says to disable band steering in this one location as a temporary work around, which we did and the troubled Apple clients started to connect. We’re finding that most clients in the complex, roughly 70% are now preferring to connect at 2.4Ghz for N & G. Previously we were about 50/50 with clients connecting at 2.4 and 5Ghz. I’ve seen other postings about band steering and Apple clients but nothing that affects Windows clients. Is this accurate and what others have seen?   Questions:   Has anyone had problems with Apple clients with their Aruba setup and band steering? Are you continuing to use band steering or is it disabled, or is it running is some locations on campus but not others? If not what else are you doing about this issue?   Those that are running Cisco or Meru (or other controller-based wireless vendors)– Are you seeing this similar issue? Is there a band steering equivalent parameter that you run?  Reason I ask is to rule this out as an Aruba only issue. I would imagine there may be a similar thing going on.   I’ve seen some emails previously on this listserv about band steering so I want to ask what you are doing about this since the semester has started and I want to determine how or if this impacts performance for both Windows and Apple clients with band steering enabled or disabled? Plus I want to hear from those that use other wireless systems to determine how these clients work with that setup. Any feedback is appreciated as we are working to debug this to the best resolution for our end user base and I’d like to know how other colleges and universities are handling this.   Thanks in advance.   --Mark Wehrle                                       Phone: (215) 898-9664   Technical Director, ISC N&T Operations            Fax:     (215) 898-9348   University of Pennsylvania   3401 Walnut Suite 221a                            Email:weh...@isc.upenn.edu   Phila. PA 19104-6228     ********** Participation and subscription information for this EDUCAUSE Constituent Group discussion list can be found at http://www.educause.edu/groups/. -- ********** Participation and subscription information for this EDUCAUSE Constituent Group discussion list can be found at http://www.educause.edu/groups/.