Thread Links Date Links
Thread Prev Thread Next Thread Index Date Prev Date Next Date Index

Re: [802.3_4PPOE] IEEE802.3 4P - Compatibility Matrix Ad-Hoc, updated meeting material.

HI Kousi,

Many thanks for your comments.

Please see my response below.



From: Koussalya Balasubramanian [mailto:kobalasu@xxxxxxxxx]
Sent: Tuesday, July 02, 2013 1:26 AM
To: Darshan, Yair; STDS-802-3-4PPOE@xxxxxxxxxxxxxxxxx
Subject: Re: [802.3_4PPOE] IEEE802.3 4P - Compatibility Matrix Ad-Hoc, updated meeting material.



  Here are few comments


Slide 5:

Change to "proposals will not imply implementation" - since we are the ones working on the objective - "will not" seems more apt that "should not"

Yair: Agree. I have updated it.


Slide 6:

 Just for readability sake, I would change it to "To present the above devices in matrix form and determine combinations that need to operate and those that need special treatment"

Yair: Agree. I have updated it.


Slide 7:

New text on slide 7 should say "…will list the proposed compatibility…."

Yair: Agree. I have updated it.



Slide 8

The proposed text in your "details of change" document is different from what the presentation has.  I would not mind if we remove this text on the whole – makes things simpler

Yair: I have updated the "details of change" document per my notes from the meeting and also the presentation and now both are sync.

I leave the text since per the correction I made, I believe it has some value. We can discuss it more over email if required.

The new text is “This ad-hoc is not collecting implementations that may or may not exist based on IEEE Std 802.3-2012.  The ad hoc is focus on what may exist and how 4P PSE/PD affects interoperability.”



Slide 9

Row 5 in the table can be contentious  - just because standard uses the term "require" instead of "receive" doesn’t mean it allows "received" - David Law might be able to help us here.  We can discuss it during tomorrow's meeting.

Yair: In this particular case, I believe that David also agree (we discuss it) that it is allowed however it is not required which is important distinction. That is why we add another column to the table to reflect this difference. The reason is that our objective is that we must keep compatibility/interoperability with devices that are required to be supported by the standard and regarding what is allowed we don’t have to. If we can it will be advantage but we don’t have to.

What is count is what appears in Slide 10 which you will see the use of "may" so if we can't support the "may" we are ok however we need to investigate it.

As you say we can discuss it at the meeting.



Slide 10

I still feel, what Dave Abramson sent was simpler – I prefer adopting that.

Yair: It is simpler since it is  not cover important devices for example:

Do you want to have only a single 4P PSE that supports output power from 30W to >60W and less than TBD? Or we want two 4P PSE with two power levels ; the first is up to 60W (natural choice and cover most use cases hence it is cost effective) and 2nd 4P with power > 60W and less than TBD so user will have a choice and will not force to use only the higher power type of 4P PSE.

The same applies for 4P PD but as I showed in the presentation, the two 4P PD power types can be merged to a single 4P PD and its power requirement can be differentiated by its class as we did with Type 1 and Type 2 PD.

The 4P PSE case is similar to Type 1 and Type 2 case in which user has the choice to use low power PSE (15.4W) and higher power PSE (30W).



Slide 11

Notes section needs to be reworded in few places – we can go over it during the meeting.

Yair: OK.







From: "Darshan, Yair" <YDarshan@xxxxxxxxxxxxx>
Reply-To: "Darshan, Yair" <YDarshan@xxxxxxxxxxxxx>
Date: Sat, 29 Jun 2013 02:19:31 +0300
To: <STDS-802-3-4PPOE@xxxxxxxxxxxxxxxxx>
Subject: [802.3_4PPOE] IEEE802.3 4P - Compatibility Matrix Ad-Hoc, updated meeting material.




Hi all,


Please see attached the results of a meeting with David Law, Fred Schindler and Yair Darshan on June 27-2013 prior the 2nd ad-hoc on July 2-2013. The purpose of the meeting was to respond to comments send by Fred Schindler, address them for helping building consensus.

Two documents are attached:

a)     details of the changes with their rational. Please review it and if you have issues with it please respond over the reflector or discuss it at the next ad-hoc. 

b)    The presentation attached includes the changes marked in blue.





Darshan Yair


Power over HDBaseT Subcommittee

HDBaseT Alliance


Chief R&D Engineer

Analog Mixed Signal Group

Microsemi Corporation


1 Hanagar St., P.O. Box 7220
Neve Ne'eman Industrial Zone
Hod Hasharon 45421, Israel
Tel:  +972-9-775-5100,

Cell: +972-54-4893019
Fax: +972-9-775-5111


E-mail: <mailto:ydarshan@xxxxxxxxxxxxx>.