There is currently no way to change the preferred band with the Apple supplicant (at the client end - although you can play tricks at the BSS to force them onto .11a). Although, there is one old software package that can do it on older systems (not likely this is of any help and isn't a free option).
The supplicant scans both frequencies, looking for the best SNR characteristics. Your experience isn't unusual as most .11a APs don't provide a hot enough signal to beat the .11bg SNR offered. In most of our companies implementation we see the opposite, but is likely due to our higher RSSI on .11a channels than seen in most all legacy implementations. Not surprising as we use a high gain antenna. Not a sales pitch here - just wanted to point out that different infrastructures will produce different behaviors. Any survey software should allow you to see the SNR characteristics for your area - this should give you a hint of what's going on with the supplicants on your notebooks. On 2/12 Apple delivered an update to Leopard 10.5's wireless drivers. After the update you should see the revs below. 1. Atheros - Wireless Card Firmware Update should be at: 1.3.2 2. Broadcom - Wireless Card Firmware Update should be at: Broadcom BCM43XX 1.0 (4.170.46.3) 3. Intel - Didn't have one at the time of this writing. You might want to try this update as the drivers solve some issues they had with MAC clients slowing their connection speeds over time and not moving to higher speeds as conditions improved. You may also find this changes your supplicant's behavior. Jon 303-808-2666 ...THE ONLY TRUE WIRELESS SWITCH...the Air is the Network... This electronic message transmission contains information from the Company that may be proprietary, confidential and/or privileged. The information is intended only for the use of the individual(s) or entity named above. If you are not the intended recipient, be aware that any disclosure, copying or distribution or use of the contents of this information is prohibited. If you have received this electronic transmission in error, please notify the sender immediately by replying to the address listed in the "From:" field. From: The EDUCAUSE Wireless Issues Constituent Group Listserv [mailto:[EMAIL PROTECTED] On Behalf Of David Wang @ UoG CCS Sent: Tuesday, February 26, 2008 8:32 AM To: WIRELESS-LAN@LISTSERV.EDUCAUSE.EDU Subject: Re: [WIRELESS-LAN] Mac issues I am new to Mac. Anyone by chance knows Leopard on MacBook or Pro (with 802.11a/b/g/n card) wireless preference: does it try a/n first? or b/g/n first? and is there any way to change it? thanks in advance. We have 802.11a and b/g available with same SSID, and find Leopards only connecting to b/g, not a. David Wang, Networking Services,CCS www.uoguelph.ca 519-824-4120 x52046 Jon Freeman wrote: Fyi - the APs require a fix as well, only Apple Airports and one other AP vendor have made the ESS fixes that I am aware of. Regards, Jon 303-808-2666 -----Original Message----- From: Lee H Badman [mailto:[EMAIL PROTECTED] Sent: Tuesday, February 19, 2008 10:48 AM Pacific Standard Time To: WIRELESS-LAN@LISTSERV.EDUCAUSE.EDU Subject: Re: [WIRELESS-LAN] Mac issues Thanks, Phil. I knew 10.5.2 was coming, just didn't realize it was actually here. It is frustrating that something that's 190 MB in size (the 10.5.2 "patch") has so little real information available on it. I dig around on several Mac forums to no avail, and find Apple's site to be almost worthless in this respect- does anyone know where any real detail on Mac updates might be available? Also- am seeing just as many trouble reports as fixes attributed to 10.5.2 during random searches- hopefully it really does help and not set us back even further. Lee ________________________________ From: Phil Trivilino [mailto:[EMAIL PROTECTED] Sent: Tuesday, February 19, 2008 1:04 PM To: WIRELESS-LAN@LISTSERV.EDUCAUSE.EDU Subject: Re: [WIRELESS-LAN] Mac issues Lee We have seen lots of failure to authenticate to our Cisco LWAPP system on startup by MAC OSX 10.5 - the recent release of 10.5.2 seems to have "fixed" that. Other MAC users across campus report improvements in wireless functionality on their Macs since the update. Sorry I do not have more specific information. Phil From: Lee H Badman [mailto:[EMAIL PROTECTED] Sent: Tuesday, February 19, 2008 12:14 PM To: WIRELESS-LAN@LISTSERV.EDUCAUSE.EDU Subject: [WIRELESS-LAN] Mac issues There is a known condition with wireless Macs where the adapter clings to bad 11a cells, even when better 11g is available- we are struggling a bit with this in certain spots right now. I'm also getting a sense that the newer Mac laptops (both MacBookPro and Air) that have 11n built in may be somewhat dodgy on our Cisco LWAPP network, though so far the evidence is circumstantial at best. Is anyone else seeing Mac-specific wireless issues? Regards- Lee Lee H. Badman Wireless/Network Engineer Information Technology and Services Syracuse University 315 443-3003 ********** 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/. ********** 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/. ********** Participation and subscription information for this EDUCAUSE Constituent Group discussion list can be found at http://www.educause.edu/groups/.