On 10/28/2011 9:58 AM, Christina Klam wrote: > Funny that you mention the issues with the HTC… I have spent the last two > days trying > to figure out why some Droid phones/tablets can get a DHCP address and others > cannot. > Moreover, if they do get an IP address, some lose their IP address after 10 > - 15 > minutes and cannot renew it. Because each device is using its own flavor of > Android > OS, I haven't been able to determine the common denominator. According to > the WCS and > debugs on WLCs, the devices are not requesting a DHCP address. (see debug > below) . > The workaround is to give the device a static IP address, have it connect to > the > network, and then uncheck the static IP box. Is this similar to what you are > seeing? > I have a case open with Cisco but they are not interested in figuring out > the problem > because "the problem is with the client. " However, according to the users, > these > clients work fine at home, in Starbucks, etc. So, to me, it is a client to > WLC issue > not just a client issue.
We have also had issues with Droids (and some other "phones") generally not refreshing all of their network attributes during power saves, roaming, and switching from cellular network to WiFi. We have a captive portal "setup" that is tied into XpressConnect that provides the configuration agent to the device (whether laptop, phone, iPad, etc). The captive portal uses DNS wildcarding to capture browser traffic and push to the portal. Browser cache often complicates this (page must be refreshed or else navigate to some non-cached destination). But this is complicated further by some devices (Droids in particular) that seem to cache their DNS lookups despite network changes where you would expect them to be flushed. And again, they don't always refresh their DHCP either on reconnect. We have seen devices continue to communicate on their cellular configuration (IP, DNS, etc) when switching to WiFi (and I would guess the converse is also true). If you are expecting something along the lines of the old WinXP "Repair" network connectivity function (where everything is reset), mobile devices leave a lot to be desired. Hopefully the network stacks of these devices will mature over time, but there are certainly some interesting challenges with them now. Jeff ********** Participation and subscription information for this EDUCAUSE Constituent Group discussion list can be found at http://www.educause.edu/groups/.
