Dear Mister Cragie, Thank you for your comprehensive reply.
> <RCC>They are outside the scope of the document because it is outside the > scope and charter of the lwig WG: > http://datatracker.ietf.org/wg/lwig/charter/</RCC> True, but contradictory : "Building a small implementation does not have to be hard. Many small devices use stripped down versions of general purpose operating systems and their TCP/IP stacks. However, there are implementations that go even further in minimization and can exist in as few as a couple of kilobytes of code, as on some devices this level of optimization is necessary. Technical and cost considerations may limit the computing power, battery capacity, available memory, or communications bandwidth that can be provided. To overcome these limitations the implementors have to employ the right hardware and software mechanisms. For instance, certain types of memory management or even fixed memory allocation may be required. It is also useful to understand what is necessary from the point of view of the communications protocols and the application employing them. For instance, a device that only acts as a client or only requires one connection can simplify its TCP implementation." > <RCC>I think such statements are unnecessary and do not add anything > constructive to the discussion. I can assure you that contributors like > Carsten and others I work with have a superior knowledge of what is required > to implement Internet protocol-based devices in low power devices with small > footprints</RCC> No. Especially, I have read with interest your presentation entitled "The ZigBee IP Stack : IPv6-based stack for 802.15.4 network", slide "IETF 6lowpan-hc adaptation layer", p.10 [0] : This is totally no sense. Where is the point of compressed IP packets on low power PANs ? > <RCC>I think it would behove the DASH7 Alliance to produce something akin to > what the BT-LE folks did, i.e. produce a draft of 6LoWPAN over DASH7. To > write off 6LoWPAN just because it was initially targeted at 802.15.4 seems > pointless; it is applicable to any low power wired or wireless technology > which uses short packets and would benefit from some header/payload > compression</RCC> There are people working on this topic : "IPv6 on wireless DASH7 links" [1]. > <RCC>In what way is 802.15.4 not open? I can download the standard from the > IEEE free of charge: > http://standards.ieee.org/getieee802/download/802.15.4-2006.pdf Yes, like DASH7. But, indeed, these two standards are flawed by design. Best Regards, [0] http://labs.chinamobile.com/attachments/wiise/MiracleW-3.pdf [1] http://kurser.iha.dk/ee-ict-master/tienprau/ProjectProposals/Communication%20Technology/Engineering%20Research%20Projects%20-%206LOWPAN%20on%20DASH7.htm Guillaume FORTAINE On Sat, Jan 28, 2012 at 3:53 PM, Robert Cragie <[email protected]> wrote: > Hi Guillaume, > > Some comments inline, bracketed by <RCC></RCC>. > > Robert > > > On 26/01/2012 6:03 PM, Guillaume Fortaine wrote: >> >> Dear Mister Bormann, >> >> Thank you for your comprehensive reply. >> >> >>> From a technical point of view, the whole point of running the 6LoWPAN >>> WG for the last half-decade was to exactly make IPv6 available for >>> constrained node/networks. That may not take away those constraints, and if >>> you want to sell something else, it may make sense to proclaim it silly. >>> Here, specifically, the guy is selling a radio that is different from >>> 802.15.4, so he's trying to malign 802.15.4, striking 6LoWPAN in passing. >>> >>> I would prefer to discuss these things from a technical angle, not by >>> pointing to content-free marketing sites/slides. >> >> If you remember my first mail on this mailing-list, I was explicitly >> asking what you called a "constrained node". Because, to quote : >> >> http://tools.ietf.org/html/draft-bormann-lwig-guidance-01 >> >> "Generic hardware design advice and software implementation techniques >> are outside the scope of this document." > > <RCC>They are outside the scope of the document because it is outside the > scope and charter of the lwig WG: > http://datatracker.ietf.org/wg/lwig/charter/</RCC> > >> >> This is totally no sense. In deeply embedded environments, we also >> need a bottom-top approach, hence my request. > > <RCC>Of course, but the IETF is not about software engineering, it is about > Internet protocols. The aim of the lwig WG is to provide guidance on the > Internet protocol parts - that is all it can do within its remit</RCC> > >> >> Especially, we can see that the people on this mailing-list (and on >> the contiki's one as well) need a serious course in Electrical >> Engineering before dreaming of designing the "Internet of the Future". > > <RCC>I think such statements are unnecessary and do not add anything > constructive to the discussion. I can assure you that contributors like > Carsten and others I work with have a superior knowledge of what is required > to implement Internet protocol-based devices in low power devices with small > footprints</RCC> > >> >> By the way, I have absolutely no affiliation with the DASH7 project. >> But, I should admit that Mister Norair made something that too few >> people are doing : his homeworks :) > > <RCC>I think it would behove the DASH7 Alliance to produce something akin to > what the BT-LE folks did, i.e. produce a draft of 6LoWPAN over DASH7. To > write off 6LoWPAN just because it was initially targeted at 802.15.4 seems > pointless; it is applicable to any low power wired or wireless technology > which uses short packets and would benefit from some header/payload > compression</RCC> >> >> >> >>> Anyway, for those who can't see this in their mail clients: the sentence >>> with "From" is mine, not from the source cited by Guillaume. Sorry for the >>> confusion. >>> >> No problem on my side : I am using Gmail :) >> >> >> Best Regards, >> >> Guillaume FORTAINE >> >> >> >> On Thu, Jan 26, 2012 at 6:49 PM, Carsten Bormann<[email protected]> wrote: >>> >>> On Jan 26, 2012, at 18:23, Guillaume Fortaine wrote: >>> >>>> Dear Dr Bormann, >>>> >>>> Thank you for your reply. >>>> >>>> >>>>> 6LoWPAN *is* plain IPv6. >>>>> I have no idea what the sentence that you are quoting is trying to say. >>>> >>>> With all the due respect, it seems that some people don't agree with you >>>> : >>> >>> Sure, some people even think that SOPA is a good idea. >>> >>>> http://dash7.org/blog/?p=1782 >>>> >>>> "(N.B. Ironically, 6LoWPAN, a wireless spec written specifically to >>>> allow IPv6 over low power wireless, is kind of silly, because it is >>>> 802.15.4 based and hence it is largely incapable of achieving any of >>>> the useful features of IPv6.)" >>> >>> >>> From a technical point of view, the whole point of running the 6LoWPAN >>> WG for the last half-decade was to exactly make IPv6 available for >>> constrained node/networks. That may not take away those constraints, and if >>> you want to sell something else, it may make sense to proclaim it silly. >>> Here, specifically, the guy is selling a radio that is different from >>> 802.15.4, so he's trying to malign 802.15.4, striking 6LoWPAN in passing. >>> >>> I would prefer to discuss these things from a technical angle, not by >>> pointing to content-free marketing sites/slides. >>> >>> Grüße, Carsten >>> >> _______________________________________________ >> Lwip mailing list >> [email protected] >> https://www.ietf.org/mailman/listinfo/lwip >> > _______________________________________________ Lwip mailing list [email protected] https://www.ietf.org/mailman/listinfo/lwip
