All:
A list of the changes that we made to the “Improving PTP Timestamping Accuracy on Ethernet Interfaces” CFI presentation is given below. Note that the new slides, 12 – 15, contain the most important changes.
-
Page numbers were added to all slides
-
Slide 2:
-
CFI objective was updated as per previous NEA teleconference
-
A name for the Study Group was also added to the CFI objective
-
Slide 3:
-
Agenda was updated to include the “Why Can’t High Accuracy Time Transport be Achieved Now?” slides
-
Slide 5:
-
The most important text on this slide was highlighted
-
Slide 6:
-
802.3cn, 802.3ct, and 802.3cp were added to the list
-
Slide 7:
-
As agreed at the previous NEA teleconference, the end of last bullet was modified to the following:
“…could limit Ethernet’s ability to support high accuracy time transport, and, thus, limit its use in C-RAN applications”
-
Slide 8:
-
Changed “legacy radio access network” to “4G radio access network” in slide header
-
Slides 12 – 15: NEW!
-
Slide 12:
-
Describes the basic problem: 802.3 does not inherently deal with varying PHY data delays and these delay variations are becoming more common
-
Slide 13:
-
Shows example data delay variations in 100GE PHY
-
Slide 14:
-
Shows basic PTP process and equations for time sync
-
Slide 15:
-
Shows the equivalent PTP process as in slide 14, but for 802.3
-
The effect of the path data delays of the 802.3 PHYs is emphasized in the time sync equations
-
Slide 16: This slide, which shows some potential improvements, used to follow the “What’s the Problem” slide (slide 7)
-
Removed 802.3’s figure 90-3 (this figure was moved to slide 12)
-
For the 1st item:
-
Added bullet stating that the measured RTT will be wrong if different message timestamping points are used
-
For the 2nd and 3rd items:
-
Modified text to highlight the data delay variance problem
-
For the 4th item, stated that this is for the potential Study Group to find and determine
-
Slide 17
-
Highlighted the right-most column, which has the net time error results
-
Added bubble to highlight that 100GE, which has a bad result, is important for C-RAN applications
-
Slide 19
-
Added some names to the contributor/supporter list
-
Slide 21
-
Added the name of the potential study group to all straw poll questions
-
Modified straw poll questions so only the total count and the total supporter count are included
-
Added a new straw poll question on affiliation support
-
Slide 22
-
The Outline of Appendices was moved to the beginning of the appendices section
Please contact me or Steve if you wish to have your name added to the contributor/supporter list or if you have any questions or comments.
Regards,
Richard Tse
Senior Technical Staff Engineer and Architect
Microchip Technology
8555 Baxter Place
Burnaby, BC
Canada
V5A 4V7
Phone: +1-604-415-6015
Email:
Richard.Tse@xxxxxxxxxxxxx
Web:
www.microchip.com
From: John DAmbrosia <jdambrosia@xxxxxxxxx>
Sent: Monday, July 8, 2019 12:29 PM
To: STDS-802-3-NGECDC@xxxxxxxxxxxxxxxxx
Subject: [802.3_NGECDC] Update - Timestamping CFI Consensus Deck
External E-Mail
All
As noted on last week’s ad hoc call, Richard and Steve were going to update their consensus deck, based on the feedback received at the call.
The file has been uploaded and may be found at - http://www.ieee802.org/3/ad_hoc/ngrates/public/calls/19_0702/tse_nea_01a_190702.pdf
Regards,
John D’Ambrosia
Chair, IEEE 802.3 NEA Ad hoc
To unsubscribe from the STDS-802-3-NGECDC list, click the following link:
https://listserv.ieee.org/cgi-bin/wa?SUBED1=STDS-802-3-NGECDC&A=1
To unsubscribe from the STDS-802-3-NGECDC list, click the following link: https://listserv.ieee.org/cgi-bin/wa?SUBED1=STDS-802-3-NGECDC&A=1