Re: [6lowpan] Question about the neighbor discovery
Erik Nordmark <nordmark@acm.org> Thu, 11 August 2011 16:33 UTC
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Date: Thu, 11 Aug 2011 09:33:33 -0700
From: Erik Nordmark <nordmark@acm.org>
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To: Damien Roth <roth@clarinet.u-strasbg.fr>
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Cc: 6lowpan@ietf.org
Subject: Re: [6lowpan] Question about the neighbor discovery
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On 8/11/11 7:16 AM, Damien Roth wrote: > 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 ? The EUI-64 is an identifier, which uniquely identifies the host whether or not the host is using a 64 bit or 16 bit link-layer address. The SLLA contains the address to which the host wants the router to send packets i.e., a locator. > 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 ? So that the packets the router forward to the host will be delivered with the short addresses in the link-layer header. Erik
- Re: [6lowpan] Question about the neighbor discove⦠Erik Nordmark
- [6lowpan] Question about the neighbor discovery Damien Roth