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[802.3_NGBASET] 40GBASE-T cabling channel webex June 7 minutes



Subject: Meeting minutes 40GBASE-T cabling channel held June 7.

Next meeting: Friday, June 21 8 AM PST webex to follow...



Discussed cabling modeling report(s) listed below- These contribution were presented at the June 5th Channel ad hoc and the June 7 Cabling ad hoc didn’t feel necessary to re-review but agreed to hear summary’s   


(1)Paul Kish

Paul Kish comments: Short length patch cord dominant factor for RL – (.5m meets Cat8 RL)   (.15 m won’t meet C8 RL) – Better RL than Cat8 can be achieved with improved components (LF/cable, HF/connector). Improvements of channel RL are observed for 4 connector vs 2 connector channels. 

(2)Sterling Vaden

Sterling Vaden comments: Component RL selected worse than Paul’s and Sterling’s results track the differences; cable structure different than Paul’s. IL model shows positive margin from Cat8 limit and further work necessary to evaluate. Sterling will contribute to touchstone format.

(3)Wayne Larsen


Chris DiMinico comment(s): It would be useful for those modeling to agree on a cable RL model…

Consider: Min patch cable to model (.15m) – [Specify insertion loss of cable (TBD)]


Reviewed possible channel configurations in source document.



Potential Path Forward for Channel Modeling Ad Hoc - updated during meeting -zimmerman_02_0513_40GBTah.pdf


Cabling ad hoc agreed to modeling configurations listed below


Ultra short patch cord in long channel - [.15m-24m-5m]

Max IL - [5m-20m-5m]

Ultra short .15-3-.15

Ugly short .5-3-.5

ISO short ref- 1-10-1

30m asym#1 1-26-3

30m asym#3 1-24-5


Modeling Volunteer list:


Discussed scope of cabling ad hoc utilizing contribution…

Chris DiMinico: >>40GBASE-T PHY-cabling ad hoc.pdf

Measurements of modeling configurations were discussed.

Agreement to generate 16 port measurements – (single ended - touchstone)


Sterling OCC

Wayne – Commscope

Mike Good  -

Bob Wagner


Peter Cibula (Intel) suggested there may be an opportunity to use Intel’s 16 port VNA for testing; to be determined as part of the measurement activity.


Chris DiMinico suggested that UNH-IOL and Agilent might be interested in supporting channel characterization.

In a message dated 6/6/2013 1:18:38 P.M. Eastern Daylight Time, CDimi80749@xxxxxxx writes:
Webex information for call tomorrow
Proposed agenda:
Discussion; Modeling and supporting measurements of "possible channel configurations" in
>>Modeling methodology - volunteers
>>Measurements - volunteers
1. Please join my meeting, Friday, June 07, 2013 at 11:00 AM Eastern Daylight Time.
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In a message dated 5/29/2013 11:22:28 A.M. Eastern Daylight Time, CDimi80749@xxxxxxx writes:
Wayne Larsen and I agreed to champion the cabling channel MDI-to-MDI efforts using the strawman process slides as a starting point  (
To coordinate efforts and to begin building consensus like to schedule weekly conference calls starting June 7 - 8 AM PST (webex to follow). 
Proposed agenda:
Discussion; Modeling and supporting measurements of "possible channel configurations" in
>>Modeling methodology - volunteers
>>Measurements - volunteers
802.3bq cabling champions
Chris DiMinico MC Communications/Panduit
Wayne Larson - Commscope
Possible Channel Configurations
•“X-Axis” – Cable classes
–A: ISO Class 1, up to 30m (x-y-z)
–B: ISO Class 2, up to 30m (x-y-z)
–C: TIA Category 8, up to 30m (x-y-z)
•Can this be merged with A?
•“Y-Axis” – Topologies/lengths
–D: Short channels
•150mm-3m-150mm (“really short”) – Worst case reflection #1
•0.5m-3m-0.5m (“pretty short”) - Worst case reflection #2
•3m - Endpoint to TOR
•5m TOR-adjacent
–E: Other target channels
•1m-10m-1m (ISO short reference channel)
•30m single patch cord (assuming there is one that meets IL…)
•30m asymmetric #1 (1m-26m-3m) – Data center configuration #1
•30m asymmetric #3 (1m-24m-5m) – Data center configuration #2
In a message dated 5/28/2013 4:21:40 P.M. Eastern Daylight Time,

Esteemed Colleagues,

Materials from the May 17th channel modeling ad hoc are posted at:


As discussed during that meeting, the next ad hoc meeting will be Wednesday, June 5th 2013 at 8:00AM PDT. 

Stay tuned for meeting information from Pete & Brad.


Thank you for your participation and contributions toward making 802.3bq the most fun project in 802.3!


David Chalupsky

Chair, 802.3bq 40GBASE-T Task Force,