[6lowpan] Question about the neighbor discovery

Damien Roth <roth@clarinet.u-strasbg.fr> Thu, 11 August 2011 14:15 UTC

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From: Damien Roth <roth@clarinet.u-strasbg.fr>
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Date: Thu, 11 Aug 2011 16:16:05 +0200
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Subject: [6lowpan] Question about the neighbor discovery
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Hello,

I'm a 2nd year PhD student and I'm trying to understand how 6LoWPAN works and there is some points I still don't understand.

During the neighbor discovery process, a host sends a Neighbor Solicitation message with an ARO and a Source Link-Layer Address option. Why is the SLLA option mandatory, since the EUI-64 is already contained in the Address Registration option ?

This leads to my second question : in the figure 5 (detailed message address examples), why does the host use its short MAC address in the SLLAO rather than its 64 bits MAC address ?

Regards,

-- 
Damien ROTH - PhD student
Strasbourg University, France