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

Re: [STDS-802-3-EPOC] Evaluation Criteria and Requirements Ad Hoc Minutes

All,

               Attached are revised minutes including the text that Marek provided describing the concerns regarding the system level requirements.

               Mark, please post.  Thanks.

Steve

From: Geoff Thompson [mailto:thompson@xxxxxxxx]
Sent: Wednesday, January 16, 2013 2:47 PM
To: STDS-802-3-EPOC@xxxxxxxxxxxxxxxxx
Subject: Re: [STDS-802-3-EPOC] Evaluation Criteria and Requirements Ad Hoc Minutes

Marek-
Just a historical note...
Such timing specifications were common for PHYs when 802.3 was specifying PHYs for CSMA/CD systems.
Round trip delay was a crucial parameter in determining the diameter of a CSMA/CD network.
The numbers used for the initial work in that area can be found in Annex B of 802.3.

It was only when we went to full duplex systems that this type of material fell into disuse.
(CSMA/CD is, of course, just an access arbitration method for TDD)

Best regards,
    Geoff

On 161//13 12:14 PM, Marek Hajduczenia wrote:
Duane,

First it would need to demonstrated that such a symmetry can be achieved with such a tight tolerance (I cannot even think or where to start to guarantee something like that), and only then draw conclusions on what the synchronization / frequency tolerance should be. Putting requirements into our project which are either system level requirements or have no evaluation as to their impact on the complexity / cost / performance of what we are trying to do, is just asking for trouble.

Let's not put the cart before the horse.

Marek

From: Duane Remein [mailto:Duane.Remein@xxxxxxxxxx]
Sent: Wednesday, 16 January, 2013 08:03 PM
To: Marek Hajduczenia; STDS-802-3-EPOC@xxxxxxxxxxxxxxxxx<mailto:STDS-802-3-EPOC@xxxxxxxxxxxxxxxxx>
Cc: Duane Remein
Subject: RE: [STDS-802-3-EPOC] Evaluation Criteria and Requirements Ad Hoc Minutes

Marek,
I agree with you that this is a system level specification. But I think we need to develop PHY level specifications that ensure a system can meet this level of synchronization. I don't think this will be much beyond adding a requirement that EPoC US path and DS path within a PHY have a symmetrical delay within some bounds (such as ± 1 or 2 TQ ). While it is true that we didn't do this for EPON we may have gotten lucky. If it is relatively easy to accomplish I think such a requirement is in order.
Best Regards,
Duane

FutureWei Technologies Inc.
duane.remein@xxxxxxxxxx<mailto:duane.remein@xxxxxxxxxx>
Director, Access R&D
919 418 4741
Raleigh, NC

From: Marek Hajduczenia [mailto:marek.hajduczenia@xxxxxx]
Sent: Wednesday, January 16, 2013 12:15 PM
To: STDS-802-3-EPOC@xxxxxxxxxxxxxxxxx<mailto:STDS-802-3-EPOC@xxxxxxxxxxxxxxxxx>
Subject: Re: [STDS-802-3-EPOC] Evaluation Criteria and Requirements Ad Hoc Minutes

Steve,

I'd like to request that the minutes reflect concerns Leo and I brought forward in relation to the frequency and synchronization precision requirements. We believe these are not PHY specific requirements, but system level requirements. If such a requirement does find its way into PHY spec, there is no way to verify it separately, i.e., nobody measures what part of the system level precision budget is consumed in PHY alone.

I'd also like to have it recorded in the minutes (as mentioned on the call) that EPON does support mobile backhaul services with *no* requirements of this type thrown into the PHY specs.

Furthermore, I believe it was also mentioned that such a requirement would overly burden devices that are not expected to carry mobile backhaul services. However, in the PHY spec it is not possible to distinguish one from another (there is just a PHY), given that 802.3 does not provide product specs. Such system level requirements should be brought forward to the group that deals with a system level design.

Regards

Marek

From: Shellhammer, Steve [mailto:sshellha@xxxxxxxxxxxxxxxx]
Sent: Wednesday, 16 January, 2013 05:04 PM
To: STDS-802-3-EPOC@xxxxxxxxxxxxxxxxx<mailto:STDS-802-3-EPOC@xxxxxxxxxxxxxxxxx>
Subject: [STDS-802-3-EPOC] Evaluation Criteria and Requirements Ad Hoc Minutes

All,

               Attached are the minutes for the Evaluation Criteria and Requirements Ad Hoc meeting this morning, and also the latest open issues list.

Steve


________________________________

________________________________

<="" p="">

________________________________

________________________________

<="" p="">

________________________________________________________________________

To unsubscribe from the STDS-802-3-EPOC list, click the following link:
https://listserv.ieee.org/cgi-bin/wa?SUBED1=STDS-802-3-EPOC&A=1

Attachment: Evaluation Criteria and Requirements Ad Hoc Minutes Jan 16 2013.docx
Description: Evaluation Criteria and Requirements Ad Hoc Minutes Jan 16 2013.docx