Subject: [eman] Requirements comments, part I

From: Bruce Nordman <[email-masked]>
Date: Fri, 8 Jul 2011 00:24:14 -0700

Much appreciation to the authors for the considerable
work and progress on this draft.  These comments as
a contributor.  I am posting in three parts due to the
large number of comments.
--Bruce

Part I:

 Terms

“building energy management” infrastructure,

  I would call these “building management” since energy may not be the
primary

  purpose – functional considerations are more likely to be primary.  This
does

  not preclude that they address energy as part of what they do.

“building networks”

  I use this term only to refer to IP networks that include non-electronic
devices

  (e.g. lights, appliances, HVAC, etc.).  I don’t use it to refer to non-IP
control

  systems.  There are a number of suitable terms like ‘building automation
systems’,

  ‘building control systems’, etc.   Since the eman protocol is indifferent
to the type

  of device so long at it is IP, we may not need the term “building network”
in the

  requirements draft (it should go into the applicability statement though)

General issues

- I think we need to introduce the concept of a device being “disconnected”

  from power.  This is a subset of the Off state.

- Related to this, devices in Off may generally lack network connectivity.

  I think we need to think through options on how to deal with this.

- There may be cases where time or energy is “missed” when devices are

  off, disconnected, and/or reset.  If a device becomes aware that it may

  have missed some time or energy, it could flag the time this occurred.

- I am not sure what “useful” means in the context of requirements.

  I suppose it could be that it is a requirement for the standard, or that

   the feature should be considered but not mandatory.

- I completely agree with the “entity” concept but do think that sometimes

  we will want to distinguish between requirements for these, for devices,

  and for components.

2.3 Powered entity

  There may be self-powered devices (e.g. energy harvesting switches or
sensors)
  on the IP network, so these won’t consume external power.  The qualifier

  “In general,” may be enough to acknowledge this edge case.

3.1 Power States

  I don’t think that “full power” and “reduced power” are different basic
types of

  power states – I think they are both forms of the on state.  Identifying
“full”

  separately is arbitrary.  (For something like a computer, “idle” is the
most common

  state so would be the one to call out separately rather than “full”)

3.3 Local and network-wide energy management

  I would drop all but first sentence of third paragraph – true but not
needed here.

-- 
*Bruce Nordman*
Lawrence Berkeley National Laboratory
eetd.lbl.gov/ea/nordman
[email-masked]
510-486-7089
m: 510-501-7943

---

From: Juergen Quittek <[email-masked]>
Date: Mon, 11 Jul 2011 13:18:02 +0000

Hi Bruce,

Thanks for your comments.
Please find replies inline.

Am 08.07.11 09:24 schrieb "Bruce Nordman" unter <[email-masked]>:

> ³building energy management² infrastructure,
>   I would call these ³building management² since energy may not be the primary

I removed "energy".

>   purpose  functional considerations are more likely to be primary.  This
> does
> ³building networks²
>   (e.g. lights, appliances, HVAC, etc.).  I don¹t use it to refer to non-IP
> control
>   systems.  There are a number of suitable terms like Œbuilding automation
> systems¹,
>   Œbuilding control systems¹, etc.   Since the eman protocol is indifferent to
> the type
>   of device so long at it is IP, we may not need the term ³building network²
> in the

I am not sure which further changes to apply. Let's discuss this for
revision -05.

> General issues
> - I think we need to introduce the concept of a device being ³disconnected²

Yes. Good point. Unfortunately too much for today. I add it as open issue.

> - There may be cases where time or energy is ³missed² when devices are
> - I am not sure what ³useful² means in the context of requirements.

I replaced most occurrences of "useful" with "required".

> - I completely agree with the ³entity² concept but do think that sometimes

OK.

>   on the IP network, so these won¹t consume external power.  The qualifier
>   ³In general,² may be enough to acknowledge this edge case.

OK.

> 3.1 Power States
>   I don¹t think that ³full power² and ³reduced power² are different basic
> types of
>   power states  I think they are both forms of the on state.  Identifying
> ³full²
>   separately is arbitrary.  (For something like a computer, ³idle² is the most
> common
>   state so would be the one to call out separately rather than ³full²)

added to the list of open issues.

>   I would drop all but first sentence of third paragraph  true but not needed
> here.

You may be right. However, this was the results of long discussions among
the authors. Let's keep it for now and discuss for future revisions. Added
it to list of open issues.

    Juergen