Re: [6lowpan] -nd-15: DAD requirement seems too strict
"Anders Brandt" <abr@sdesigns.dk> Fri, 25 February 2011 13:52 UTC
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Date: Fri, 25 Feb 2011 14:53:08 +0100
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From: Anders Brandt <abr@sdesigns.dk>
To: Colin O'Flynn <coflynn@newae.com>, zach@sensinode.com, 6lowpan <6lowpan@ietf.org>
Subject: Re: [6lowpan] -nd-15: DAD requirement seems too strict
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Hi Colin >If you had a closed network where you don't have the 'idiot node' >picking addresses randomly in your space, you could skip DAD. But >I think if you had such a closed network you wouldn't care enough >about sticking to the RFCs anyway. To some extent this ties to the link-layer bootstrapping process. I know at least one link-layer technology which does guarantee unique link layer addresses. Still, I consider the ND doc highly useful and see several reasons for sticking to it if possible. And anyway, the document seems to be in conflict with itself on this issue ... Cheers, Anders -----Original Message----- From: Colin O'Flynn [mailto:coflynn@newae.com] Sent: 25. februar 2011 14:42 To: Anders Brandt; zach@sensinode.com; '6lowpan' Subject: RE: [6lowpan] -nd-15: DAD requirement seems too strict Hi Anders, I'm still reading through -15 too, so just wanted to add other comments. I think part of the problem is you can register any address you want, not necessarily one based on a MAC address. EUI64-based addresses can be globally unique, so you can reliably skip DAD on those. An address generated from a MAC address, if that MAC address is not globally unique, could potentially collide with another address. This is very unlikely, as someone would have to randomly choose an IPv6 address in the same space as your MAC-address-derived space. If you had a closed network where you don't have the 'idiot node' picking addresses randomly in your space, you could skip DAD. But I think if you had such a closed network you wouldn't care enough about sticking to the RFCs anyway. Regards, -Colin -----Original Message----- From: 6lowpan-bounces@ietf.org [mailto:6lowpan-bounces@ietf.org] On Behalf Of Anders Brandt Sent: February 25, 2011 11:10 AM To: zach@sensinode.com; 6lowpan Subject: [6lowpan] -nd-15: DAD requirement seems too strict Having read the doc carefully, I have a question: The doc is somewhat scizophrenic whether it accepts that a link layer can guarantee unique short addresses. Assumption #6 in section 1.3 seems to say "OK" Section 3.2 says that if I do not use DHCPv6 (M flag = 1) I MUST use DAD. I would like this softened to "MUST use DAD if the LOWPAN cannot guarantee unique short addresses" Thanks, Anders -----Original Message----- From: 6lowpan-bounces@ietf.org [mailto:6lowpan-bounces@ietf.org] On Behalf Of Carsten Bormann Sent: 17. februar 2011 16:58 To: 6lowpan Subject: [6lowpan] Working Group Last call for draft-ietf-6lowpan-nd-15 In September/October, we had the first WGLC on 6LoWPAN-ND, which resulted in a number of detailed comments and two resulting fine-tuning iterations of the draft. draft-ietf-6lowpan-nd-15.txt has been out for two months now. I understand it has taken part in several interops with multiple implementations in this period; no issues came up. We now start the Working Group Last Call on: http://tools.ietf.org/html/draft-ietf-6lowpan-nd-15 The document is planned to be submitted by this Working Group to the IESG for publication as a Standards-Track Document. This is a two-week Working-Group Last-Call, ending on Thursday, 2011-03-03 at 2359 UTC. Please review the changes to the document carefully once more, and send your comments to the 6lowpan list. Please also do indicate to the list if you are all-OK with the document. Gruesse, Carsten _______________________________________________ 6lowpan mailing list 6lowpan@ietf.org https://www.ietf.org/mailman/listinfo/6lowpan _______________________________________________ 6lowpan mailing list 6lowpan@ietf.org https://www.ietf.org/mailman/listinfo/6lowpan
- Re: [6lowpan] "Advertize on Behalf" flag in ARO Mukul Goyal
- [6lowpan] Working Group Last call for draft-ietf-… Carsten Bormann
- Re: [6lowpan] Working Group Last call for draft-i… Don Sturek
- Re: [6lowpan] Working Group Last call for draft-i… Pascal Thubert (pthubert)
- [6lowpan] -nd-15: DAD requirement seems too strict Anders Brandt
- [6lowpan] -nd-15: Joining the all-nodes multicast… Anders Brandt
- [6lowpan] -nd-15: Battery host support seems to b… Anders Brandt
- [6lowpan] -nd-15: Purpose of SLLA slightly unclear Anders Brandt
- [6lowpan] 6lowPAN HC in context of draft-thubert-… Anders Brandt
- Re: [6lowpan] -nd-15: Joining the all-nodes multi… Colin O'Flynn
- Re: [6lowpan] -nd-15: Joining the all-nodes multi… Anders Brandt
- Re: [6lowpan] -nd-15: DAD requirement seems too s… Colin O'Flynn
- Re: [6lowpan] -nd-15: DAD requirement seems too s… Anders Brandt
- Re: [6lowpan] -nd-15: Battery host support seems … Mukul Goyal
- Re: [6lowpan] Working Group Last call for draft-i… Dijk, Esko
- [6lowpan] "Advertize on Behalf" flag in ARO Mukul Goyal
- Re: [6lowpan] Working Group Last call for draft-i… Mathieu Goessens
- Re: [6lowpan] Working Group Last call for draft-i… Noriyuki SATO
- Re: [6lowpan] "Advertize on Behalf" flag in ARO Mukul Goyal
- Re: [6lowpan] "Advertize on Behalf" flag in ARO Erik Nordmark
- Re: [6lowpan] -nd-15: Joining the all-nodes multi… Erik Nordmark
- Re: [6lowpan] "Advertize on Behalf" flag in ARO Dijk, Esko
- Re: [6lowpan] "Advertize on Behalf" flag in ARO Carsten Bormann
- Re: [6lowpan] "Advertize on Behalf" flag in ARO Pascal Thubert (pthubert)
- Re: [6lowpan] "Advertize on Behalf" flag in ARO Carsten Bormann
- Re: [6lowpan] "Advertize on Behalf" flag in ARO Mukul Goyal
- Re: [6lowpan] -nd-15: Joining the all-nodes multi… Erik Nordmark
- Re: [6lowpan] "Advertize on Behalf" flag in ARO Anders Brandt
- [6lowpan] How to find the mailbox? (related to "A… Anders Brandt
- Re: [6lowpan] "Advertize on Behalf" flag in ARO Dijk, Esko
- Re: [6lowpan] "Advertize on Behalf" flag in ARO Pascal Thubert (pthubert)
- Re: [6lowpan] "Advertize on Behalf" flag in ARO Pascal Thubert (pthubert)
- Re: [6lowpan] How to find the mailbox? (related t… Richard Kelsey
- Re: [6lowpan] How to find the mailbox? (related t… Jonathan Hui
- Re: [6lowpan] How to find the mailbox? (related t… Pascal Thubert (pthubert)
- Re: [6lowpan] How to find the mailbox? (related t… Noriyuki SATO
- Re: [6lowpan] "Advertize on Behalf" flag in ARO Erik Nordmark
- Re: [6lowpan] "Advertize on Behalf" flag in ARO Erik Nordmark