This is what we heard from our SE concerning our Macintosh connectivity
issues -- although i quote "This is my personal view on the issues I
have seen, and are not to be taken as an official word on the problem
from the big C..."
However the latest version of drivers are supposed to fix these problems
-- especially the roaming.
*****************************
Basically, we have seen 2 issues with Macs.
One issue has to do with the way the MAC does DHCP, and specifically
DHCP renewing of leases. The Mac implements a newer RFC which attempts
to use old DHCP lease information if there is still time available on
the lease. It does this without going through the "normal" DHCP lease
refresh process. If the controller is configured to "require DHCP" then
the controller will not know what to do with the packets from the Mac
until it goes through the normal dhcp lease process. The Mac will
eventually go though a full DHCP process and "fix" itself, but then
process can take a period of time. The workaround for this is to remove
the "DHCP required" checkbox on the WLAN.
The other issue has to do with Mac roaming. This issue is being
addressed by Apple with new drivers. The reality is that the Apples
were build for hotspot type access where it tried to hang on the AP
until the signal goes all very low (to 0 SNR in some cases). Apparently
Apple is rewriting their wireless stack to give better roaming
performance, but I am not sure when Apple will release the driver.
*****************************
Angela K Hollman wrote:
I have noticed the Macs failure to get an IP even though they pass the
802.1x authentication. This problem seemed to get a lot better moving
from 10.4 to 10.5 and even a little better with the latest 10.5
releases. However, when a client first authenticates after having
their computer off-campus, it seems the Airport has to be toggled off
and back on once or twice before the Mac receives an IP. I have been
getting the information out to Mac users to toggle the Airport off and
back on but the problem is very annoying.
I have not noticed any of the 11a problems mentioned.
_________________
Angela K. Hollman
Information Technology Services
Network Manager
(308)865-8176
From: Lee H Badman <[email protected]>
To: [email protected]
Date: 01/22/2009 10:58 AM
Subject: [WIRELESS-LAN] Macintosh- Ongoing Connectivity Issues
Sent by: The EDUCAUSE Wireless Issues Constituent Group Listserv
<[email protected]>
------------------------------------------------------------------------
We saw this in earlier versions of OS X, then things got better with
some of the earlier 10.5.x code, but now seems to be getting worse
again. Wondering if anyone else is seeing Mac behavior along these
lines on the latest Apple code versions including 10.5.6:
* Clients will associate to lesser-quality 11a cells even though
better 11g signal is present (FREQUENT)
* Clients will stick to the 11a AP they associate with even when
they have the opportunity to move to better (stronger, less
users, good SNR) 11a signal (FREQUENT)
* Clients appear to be fine in every way- good association, good
SNR and signal strength, pass 802.1x authentication, all
indications are fine. Yet they have difficulty getting IP
address or doing anything else despite their nearby peers having
no issues at all, in cells that are not overtaxed. (LESS FREQUENT)
We have about 35% Macintosh penetration among our 5-6 thousand user
per day client count. But of late, every wireless client issue not
easily resolved seems to be with Mac hardware doing the above described.
Is any one else feeling these symptoms?
-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
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********** Participation and subscription information for this
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--
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
Kristina Gasca, Wireless Network Engineer
North Carolina State University
Communication Technologies
919.515.0107 (office)
919.515.1641 (fax)
[email protected]
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
**********
Participation and subscription information for this EDUCAUSE Constituent Group
discussion list can be found at http://www.educause.edu/groups/.
