Re: [lp-wan] overview draft with some text...

[Jiazi Yi <[e-mail]>]

Hi, 


> On 30 Oct 2016, at 00:46, Stephen Farrell <[e-mail]> wrote:
> 
> 
> Hiya,
> 
> On 29/10/16 23:19, Jiazi Yi wrote:
>> Dear Stephen,
>> 
>> Thanks a lot for the work!
>> 
>> A general comment before going into details:
>> 
>> When introducing characteristics and performance of different
>> technologies, I think we need to pay attention that:
>> 
>> 1) focus on the objective characteristics, such as frequency band,
>> bandwidth, data rate, etc. I would avoid using text like “foo has
>> battery life of XXX years” or “bar can support YYY devices in a
>> single cell”. Those kind of characteristics depend on highly on the
>> configuration of the network, application traffic pattern, network
>> environment, etc. It’s very hard to extract useful information from
>> such kind of assertions.
> 
> Fully agree with editing out any such statements. Feel free to
> point out any that are in there now, but I'll also do a pass for
> that myself later on.

Some examples:

4.2.2:
Specific targets for NB-IoT include: <snip>  battery life of
  over 10 years, ~55000 devices per cell …

4.3.2:
   SIGFOX LPWAN autonomous battery-operated devices send only a few
   bytes per day, week or month, allowing them to remain on a single
   battery for up to 10-15 years.

> 
>> 
>> 2) For each technology, we talk only the current characteristics, not
>> the targeting characteristics (especially those long target).
> 
> I'm not sure I agree there. If there are changes planned that'd
> happen in the next say 5 years, then it seems like those would
> be fine input for the WG to consider.

I agree. 

> Of course, I do agree that
> the WG will need to be exercise judgement about how they consider
> any such plans, as we're all prone to being a bit optimistic
> about the future:-)
> 
> FWIW, I think anything written down as an IETF contribution or
> that can be referenced from one should be good input to the WG.
> 
> What the WG choose to conclude from such input is of course
> another question. But that's just me. Whether or not the WG have
> consensus to regard some input or claim as outlandish or worth
> documenting and analysis is not my call.
> 
>> 
>> 3) It’s welcome to report implementation status of different
>> technologies, but if the contributors choose to do so, please provide
>> a bit more details (such as the scale of the deployment, applications
>> running over it, etc.), with appropriate references.
> 
> I'm curious myself about some of the current implementations and
> deployments and whether those might constrain the work here. But
> I'm not clear about the level of detail the WG need about that.

Personally, I’m very interested in knowing the current deployment status. If such information could be disclosed, even if briefly, would be welcome. But I would like to see the technical aspects of the deployments to understand how they works. 

For example, when reading:

As of today, the SIGFOX LPWAN/LTN has been fully
   deployed in 6 countries, with ongoing deployments on 14 other
   countries, which in total will reach 316M people.

I would like to know at least: how many devices are actually deployed? What’s the typical coverage of a cell? What’s the maximum number of sensors in a cell? What does the traffic look like? 

> 
>> 
>> The purpose is to have an objective standard as possible for all the
>> technologies listed in the draft. We have to admit that, although we
>> (all?) agree, and called out explicitly that this document is NOT
>> intended to compare which technology is better, we couldn’t stop the
>> readers from making such kind of comparison.
> 
> Not sure I'm following the point there.
> 
> One thing I do think though - regardless of whether or not the
> WG decide this draft ought end up as an RFC, we still only need
> the text here to be sufficiently clear for the WG to do it's
> job. And if we aim for perfect wording then we'll probably take
> a lot of time to just not achieve that. So while we do need to
> ensure that the overall text doesn't give a wrong impression, I
> figure being careful to not waste time aiming for a non-useful
> level of perfection will be better.

Agree. The point I want to make is that we use clear and technical text, and avoid marketing words. 

cheers

Jiazi

> 
> Cheers,
> S.
> 
> 
>> 
>> regards
>> 
>> Jiazi
>> 
>>> On 29 Oct 2016, at 01:57, Stephen Farrell
>>> <[e-mail]> wrote:
>>> 
>>> 
>>> Hiya,
>>> 
>>> I've incorporated descriptive text about some of the "input"
>>> technologies for lpwan in -01 of the overview draft. [1] That
>>> includes text from a lora draft that Alper and I also posted
>>> recently [2] and from the existing sigfox and nb-iot drafts. Next
>>> up will be adding text from the gap analysis work in the places 
>>> indicated. I hope to post that before the cutoff. We may also get
>>> text on WI-SUN by then too.
>>> 
>>> Comments on any inaccuracies or omissions in [1] are of course very
>>> welcome. There's a github repo [3] if anyone prefers that. (Though
>>> my github foo is modest so bear with me if taking that approach:-)
>>> I'll make sure that any substantive discussion initiated on github
>>> is reflected to the list.
>>> 
>>> Cheers, S.
>>> 
>>> [1] https://tools.ietf.org/html/draft-farrell-lpwan-overview-01 [2]
>>> https://tools.ietf.org/html/draft-farrell-lpwan-lora-overview-01 
>>> [3] https://github.com/sftcd/lpwan-ov
>>> 
>>> 
>>> _______________________________________________ lp-wan mailing
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>> 
>> 
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