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Passing this along…IT guy at the prep school got back to me.


Their WLAN is the H3C gear that 3Com had licensed, now part of HP. New last year.


Researching, they found this comment (below) from another HP/H3C customer site, which indicates one explanation for the problem at least with H3C gear: it has to do with the “extended capabilities” tag, which apparently was modified in the IEEE 802.11-2012 standard. From what I can tell, there’s a mismatch between Apple and HP’s support of the most recent standard, which is read as a fatal error by the network.


Here’s the excerpt he sent me:

Now, the "IEEE Std 802.11n-2009" states that this parameter should have only 3 as valid length. Contrary to that, the current "IEEE Std 802.11-2012" defines the valid length between 3 and 8.

It seems that our HP/H3C equipment treats "Extended Capabilities" parameter length == 4 as fatal error and rejects the association (instead of just ignoring this parameter).

From the formal point of view, Apple's implementation is correct, and HP should correct its firmware. We've got in touch with HP about this issue and are now awaiting their response.

Nevertheless, I hope that Apple updates iOS 6 that no "Extended Capabilities" parameter is sent during association, since its purely redundant, as it contains just..[the rest of this post is a table of the various entries, which is shown in linked post].


It seems unlikely to me that Apple will deviate from a standard that it’s embraced.



John Cox

Senior Editor


Network World

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