On Tue, 24 Jul 2007, Frank Bulk wrote: See: http://www.cisco.com/warp/public/707/cisco-sa-20070724-arp.shtml -Hank
Duke runs both Cisco's distributed and autonomous APs, I believe. Kevin's report on EDUCAUSE mentioned autonomous APs, but with details as hazy as they are right now, I don't dare say whether one system or another caused or received the problem.
Frank
-----Original Message----- From: owner-nanog@merit.edu [mailto:owner-nanog@merit.edu] On Behalf Of Dale W. Carder Sent: Sunday, July 22, 2007 2:51 PM To: Bill Woodcock Cc: Sean Donelan; North American Network Operators Group Subject: Re: iPhone and Network Disruptions ...
On Jul 21, 2007, at 8:52 PM, Bill Woodcock wrote:
Cisco, Duke has now come to see the elimination of the problem, see: "*Duke Resolves iPhone, Wi-Fi Outage Problems"* at http://www.eweek.com/article2/0,1895,2161065,00.asp
it's an ARP storm, or something similar, when the iPhone roams onto a new 802.11 hotspot. Apple hasn't issued a fix yet, so Cisco had to do an emergency patch for some of their larger customers.
As I understand, Duke is using cisco wireless controllers to run their wireless network. Apparently there is some sort of interop issue where one system was aggravating the other to cause arp floods in rfc1918 space.
We've seen 116 distinct iphones so far on our campus and have had sniffers watching arps all week to look for any similar nonsense. However, we are running the AP's in autonomous (regular ios) mode without any magic central controller box.
Dale
-- Dale W. Carder - Network Engineer University of Wisconsin at Madison / WiscNet http://net.doit.wisc.edu/~dwcarder