Re: [Madwifi-devel] possible error when de-capsulating packets?
Status: Beta
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From: Alfred A. <al...@cc...> - 2007-08-24 06:03:31
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Hi, this check in MADwifi is probably correct. The basic problem is that there is no Ethernet II framing on 802.11, so Ethernet packets with Ethernet II framing have to be packet into an LLC-SNAP header. However, there are protocols (mainly IPX and Appletalk) that can be transmitted as plain Ethernet or LLC-SNAP on the 'wired' side. So there must be a way to tell the receiver whether the LCC-SNAP header (which is always present on the WLAN, regardless whether it was present on the the Ethernet or not) shall be stripped off or not. IEEE 802.1h (freely available from IEEE) describes the dirty details how this is done. The real question is why your AP packs the ARP frame into an LLC-SNAP header with the vendor OID set to 00-00-f8 instead of 00-00-00. You may look into the config of your AP for something like a 'SNAP type table'. Best regards Alfred Arnold -- Alfred Arnold E-Mail: al...@cc... Computer Club at the http://john.ccac.rwth-aachen.de:8000/alf/ Technical University Phone: +49-241-406526 of Aachen Fax: +49-241-406527 |