Hi Heath,
I have made this statement in earlier cycles, however it is incorrect.
We know the PSE is not required to police the PD, this remains true.
I knew of no text or requirement that disallowed a PD from asking over DLL any amount of power, therefore, it could ask for any amount regardless of the requested Class.
Today I discovered this:
Permitted values for PDRequestedPowerValue only go up to PD_DLLMAX_VALUE.
Which is:
The value is set by pd_max_power, which is the initial value the PD gets from Physical Layer.
In other words: the assigned Class. Which means that per the D2.3 text, if a PD gets demoted, it can't even ask it's requested Class.
yseboodt_04 fixes that, and replaces pd_max_power by pd_req_class for the PD_DLLMAX_VALUE, thereby allowing a PD to DLL up to its requested Class.
Given all that, the statement you refer to is no longer needed.
Kind regards,
Lennart
Sent: Thursday, March 2, 2017 22:29
To: STDS-802-3-4PPOE@xxxxxxxxxxxxxxxxx
Subject: Re: [802.3_4PPOE] yseboodt_03_0317: PD Classification text
Make sense.
Yair
From: David Stover [mailto:00000687aebafbf1-
dmarc-request@xxxxxxxx ]
Sent: Thursday, March 02, 2017 9:09 PM
To: STDS-802-3-4PPOE@LISTSERV.IEEE.ORG
Subject: Re: [802.3_4PPOE] yseboodt_03_0317: PD Classification text
EXTERNAL EMAIL
George,
Clear and obvious break between two statements to promote "shall" language to front of its own sentence; make it more obvious. I like it.
Another observation I had (discussed offline with Lennart), is that the clean-up obviates two "shall" in this section that have a confusing interaction:
Statement #1 (GZ edit): "The PD shall draw no more power across all input voltages than the requested Class during Physical Layer classification..."
Statement #2: "The PD shall conform to the assigned Class, regardless of its requested Class"
I believe we mean to convey:
* If assigned < requested, PD shall conform to assigned Class
* If assigned > requested, PD shall conform to requested Class
where "requested" is "the requested Class during Physical Layer classification".
Then, I recommend we also modify...
From: "The PD shall conform to the assigned Class, regardless of its requested Class"
To: "The PD shall conform to the assigned Class or the class requested by the PD during Physical Layer classification, whichever is lower."
Cheers,
David Stover II
On Thu, Mar 2, 2017 at 8:20 AM, George Zimmerman <george@xxxxxxxxxxxxxxxxxxxx> wrote:
Lennart –
This is a good improvement.
There is one ‘shall’ however (which we discussed offline) that is written in so soft a way that it gets lost. All the other ones are written as “the PD shall.. xyz”. This one is a tacked on clause at the end:
The requested Class of the PD is the Class the PD advertises during Physical Layer classification, and represents the maximum
power, as defined in Table 145–24 and Table 145–25, that a PD shall draw across all input voltages.
I suggest the following:
The requested Class of the PD is the Class the PD advertises during Physical Layer classification.
The PD shall draw no more power across all input voltages than defined for the class it advertises during Physical Layer classification in Table 145–24 and Table 145–25.
This way the shall is clearly stated as an active requirement and not just tacked on at the end of a sentence, likely to get lost
From: Yseboodt, Lennart [mailto:lennart.yseboodt@
PHILIPS.COM ]
Sent: Thursday, March 02, 2017 5:20 AM
To: STDS-802-3-4PPOE@LISTSERV.IEEE.ORG
Subject: Re: [802.3_4PPOE] yseboodt_03_0317: PD Classification text
Updated version attached, incorporating comments from Yair and Chad.
With regard to the ‘connected to a Type 4, Class 8 PSE’ I have used different wording which I think better explains the intent.
Saying Type 4 / Class 8 is factually incorrect. What we mean to say is that it takes up to 3 class events to really discover the requested Class of the PD.
Kind regards,
Lennart
From: Chad Jones (cmjones) <cmjones@xxxxxxxxx>
Sent: Wednesday, March 1, 2017 23:47
To: Yseboodt, Lennart; STDS-802-3-4PPOE@LISTSERV.IEEE.ORG
Subject: Re: [802.3_4PPOE] yseboodt_03_0317: PD Classification text
Mutual ID is the term we invented for AT and I think it is appropriate to keep it in BT.
Additionally, classification is used to establish mutual identification between the PSE and the PD to discover each others’ Type.
This text:
The requested Class of the PD is the Class the PD advertises during Physical Layer classification, and represents the maximum power, as defined in Table 145–24 and Table 145–25, that a PD shall draw across all input voltages.
I had a similar comment and I agree with what you did here but I think you deleted a relevant piece of information: “The requested Class of the PD is the Class a PD advertises during Physical Layer classification when connected to a Type 4, Class 8 PSE;”. The ‘connected to a Type 4, Class 8 PSE’ phrase struck me as odd at first but then it became clear that this is a way of saying request the max power on the physical layer. I think it is important to leave in. So I would say add the phrase “when connected to a Type 4, Class 8 PSE” back to your sentence.
Chad Jones
Tech Lead, Cisco Systems
Chair, IEEE P802.3bt 4PPoE Task Force
From: "Yseboodt, Lennart" <lennart.yseboodt@xxxxxxxxxxx>
Reply-To: "Yseboodt, Lennart" <lennart.yseboodt@xxxxxxxxxxx>
Date: Wednesday, March 1, 2017 at 1:35 PM
To: 4PPOE Reflector <STDS-802-3-4PPOE@LISTSERV.IEEE.ORG >
Subject: [802.3_4PPOE] yseboodt_03_0317: PD Classification text
Hello,
We saw significant changes to the PD classification text due to the Clause split, on top of a nice cleanup action by Heath adopted in January.
Some rectification and further cleanup attached.
Comments welcomed.
Kind regards,
Lennart