Thanks for this URL. Reminds me of the Apple iPhone/Cisco Wi-Fi network issue.
Frank -----Original Message----- From: The EDUCAUSE Wireless Issues Constituent Group Listserv [mailto:[email protected]] On Behalf Of Dale W. Carder Sent: Thursday, January 22, 2009 9:49 PM To: [email protected] Subject: Re: [WIRELESS-LAN] Macintosh- Ongoing Connectivity Issues Frank, I think the dhcp issues have been related to rfc 4436. Also, see this thread for other issues apple's implementation of dnav4 has had historically. http://lists.sans.org/pipermail/unisog/2007-January/027056.html Dale On Jan 22, 2009, at 9:27 PM, Frank Bulk wrote: > Kristina: > > Is the SE talking about using DHCP INFORM instead of DHCP RENEW? > > Frank > > -----Original Message----- > From: The EDUCAUSE Wireless Issues Constituent Group Listserv > [mailto:[email protected]] On Behalf Of Kristina > Gasca > Sent: Thursday, January 22, 2009 5:58 PM > To: [email protected] > Subject: Re: [WIRELESS-LAN] Macintosh- Ongoing Connectivity Issues > > 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 >> 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/. >> > > -- > ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ > 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/. > > ********** > 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/.
