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Re: [802.3_4PPOE] Clause 33 TOC (hybrid split)

Hi Lennart,
Sorry for the long email but I believe it will help to everyone to understand the issue.
See also examples below that illustrate the concerns that I have.
1. I don’t see that this outline is addressing the problems that we discussed during your first proposal for two PoE chapters.
2. Separation of PSE Type 1 and 2 from Type 3 and 4 is almost the same of two chapters. It is just different package.
    Now you increase the problems with a factor of 2. It will be 4 subclauses (i.e. ="4 chapters") that we need to jump from and 2 to understand what are the requirements instead of simple 1 PoE clause that address all PoE types.
3. You still didn’t show us the problem why you want to do this. You said that it is hard to read and we all agree that it is because of the Type 3 and 4 new material and not due to Type 1 and 2 which is simple.
So I still suggest that we focus on enhancing the readability and clarity of the Type 3 and 4 parts.
We are almost there, no need for shuffling the cards and create new problems while clarity will not be improved.
4. In you proposal the common parts are 33.1 Overview,  and 33.4 to 33.10 which are common for all type which is OK but the problem that motivated you to suggest 2 chapter and now 4 clauses was not solved. You still need to improve Type 3 and 4 text…
5. You still duplicate most of the requirements for Type 1,2,3, and 4.
6. We still will have the following problems:
5.1 the user will have to jump between 4 chapters (now it is 4 subclauses) to look for information and compare.
5.2 We will have the risk of braking things because they are not summarized in the same tables e.g. 33-11 and 33-18 as today and drawings etc.
5.3 It will be still  much larger document that we have today, more comments, more delays
As an alternative I suggest the following:
33.1 Overview
33.2 Power Sourcing Equipment (PSE) .
33.2.4 PSE Type 1 / 2 State diagram
33.2.5 PSE Type 3 / 3 State diagram
33.2.6 Detection   
33.2.7 Type 1 Type 2 :PSE Classification of PDs and mutual identification
33.2.8 Type 3 Type 4 :PSE Classification of PDs and mutual identification
Etc. e.g.
33.X.Y PSE POWER UP (For all types) internally you can differentiate between the Types. Any how I have checked it too and there is small leffect on clarity, but possible.
33.X.z PSE POWER ON (For all types) internally you can differentiate between the Types.    
The same applies to PD.
However in the PD is much easier to keep the same requirement as it is constructed today and only separate state machine to two lower level subclauses. Again, the impact on clarity is very limited.
33.TBD Powered Devices (PD).
33.6 to 33.10 are the same for all Types as you indicated.
See examples how clarity will be broken with your proposal:
Example 1: This is the current spec of the PD. Yellow marks are Type 1/2 words or sentences. You can see that it doesn’t affect clarity and if you move all of it to separate clause without them, you will gain nothing.
2. In the current spec all the information for all Types are in the same table. Easy to read, to compare, to evaluate and make sure that we are not breaking things. Duplicating the tables for two PD clauses and removing the occurrences where the parameter is relevant to Type 1 and 2, will reduce clarification and be unfriendly to the end user that will have to jump between clause seeking for valuable information while today all is in one table.
3 Last example: The main question that I still didn’t get an answer: How by removing Type 1 and 2 text from PD clause will improve clarity?
-----Original Message-----
From: Yseboodt, Lennart [mailto:lennart.yseboodt@xxxxxxxxxxx]
Sent: Thursday, November 12, 2015 1:27 AM
To: STDS-802-3-4PPOE@xxxxxxxxxxxxxxxxx
Subject: [802.3_4PPOE] Clause 33 TOC (hybrid split)
Hi all,
I've created a sample TOC for a hybrid-split Clause 33, to make sure we all understand what the proposal is.
A new Clause 33
Table of contents
33. Data Terminal Equipment Power via Media Dependent Interface
        33.1 Overview
        33.2 Type 1 and Type 2 Power Sourcing Equipment (PSE) . Yair: This should be with the same sub clause with Type 3 and 4.
        33.3 Type 1 and Type 2 Powered Devices (PD). Yair: This should be with sub clause 33.2.
        33.4 Type 3 and Type 4 Power Sourcing Equipment (PSE)
        33.5 Type 3 and Type 4 Powered Devices (PD)
        33.6 Additional electrical specifications Yair: OK
        33.7 Management function requirements Yair: OK
        33.8 Data Link Layer classification Yair: OK
        33.9 Environmental Yair: OK
        33.10 PICS Yair: OK