enterprise 802.11

Jared Mauch jared at puck.nether.net
Mon Jan 16 17:05:17 UTC 2012

On Jan 16, 2012, at 11:52 AM, Tim Franklin wrote:

>> As for the iOS problem, read on here:
>> http://www.net.princeton.edu/apple-ios/ios41-allows-lease-to-expire-keeps-using-IP-address.html
> That's the iOS issue - out of curiosity, what's the Mac issue?

That's a poorly maintained device issue.  The good news is the DHCP requests for those devices (if you log them) commonly include information about the device owner, e.g.:

Jan 15 16:56:35 nat dhcpd[1046]: DHCPACK on to 18:e7:f4:5c:b1:d7 (MATTS-IPOD-3) via eth0


  client-hostname "iPhone-Touch";
  client-hostname "Her-iPod";
  client-hostname "iPad";
  client-hostname "Amys-iPod";

Also, citing a single software release with a defect can be done for any platform.


These issues are commonly solved by upgrading to the most recent release of software.  Reading the princeton article says setting your lease time to 3600 seconds seems to workaround the problem from the network side.  I'm personally not convinced of the value of very short lease times (less than an hour).  Even IPv6 privacy addresses stay around longer than that.

MacOS Kernel (11.2.0)

net.inet6.ip6.temppltime: 86400
net.inet6.ip6.tempvltime: 604800

Linux Kernel (3.1.1)
net.ipv6.conf.default.use_tempaddr = 0
net.ipv6.conf.default.temp_valid_lft = 604800
net.ipv6.conf.default.temp_prefered_lft = 86400

net.inet6.ip6.use_tempaddr: 0
net.inet6.ip6.temppltime: 86400
net.inet6.ip6.tempvltime: 604800

- Jared

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