Re: [6lowpan] ND-17 / DNS support

Carsten Bormann <cabo@tzi.org> Thu, 26 January 2012 17:24 UTC

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From: Carsten Bormann <cabo@tzi.org>
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Date: Thu, 26 Jan 2012 18:24:36 +0100
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To: "Dijk, Esko" <esko.dijk@philips.com>
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Subject: Re: [6lowpan] ND-17 / DNS support
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On Jan 26, 2012, at 16:35, Dijk, Esko wrote:

>> The same is true for TBD1 (31) and TBD2 (32), which have been assigned in the meantime:
>> 31      DNS Search List Option                  [RFC6106]
>> 32      Proxy Signature (PS)                    [RFC-ietf-csi-proxy-send-05.txt]
> 
> #31 triggered me: should 6lowpan-ND mention anything about support of the RDNSS option in RFC6106?

I don't think so, from my point of view the two are orthogonal (i.e., 6LoWPAN neither excludes nor optimizes RDNSSO).

(But maybe the way 6LoWPAN-ND and the other ND options fit together is a nice subject for a section in the LWIG guidance document.)

> Supporting would allow 6LBR/6LRs to e.g. distribute an address of a DNS server to all 6LNs. Or are there better alternatives for a 6LN to obtain a DNS server? In many use cases DNS is an essential service component, see. e.g. draft-vanderstok-core-bc-05.

*If* your 6LoWPAN nodes need a DNS server, they should get it either using RDNSSO (and, heaven forbid, DNSSLO) or, if they are already using DHCPv6 for other reasons, using that.
(We at least used to have a sizable group of DHCPv6 fans in the 6LoWPAN WG, so I'm not sure we can really recommend either.)

Grüße, Carsten