Re: [802.3_100GCU] Successful May Interim

[Brad Booth <bjbooth@xxxxxxxxx>]

Thanks Chris, that would be greatly appreciated.

 

Cheers,

Brad

On Tue, May 31, 2011 at 2:53 PM, <Christopher> <DiMinico> <CDimi80749@xxxxxxx> wrote:

Brad,

 

I understand your point but agree with Steve on objectives not needing to nail down every detail. However, I'm willing to provide more information on 24 AWG twinaxial mechanical characteristics to enable a better understanding of performance attributes; to follow before IEEE 802 July plenary.

 

Regards, Chris

 

 

 

 

In a message dated 5/31/2011 3:20:17 P.M. Eastern Daylight Time, steve.trowbridge@xxxxxxxxxxxxxxxxxx writes:

Hi Brad,

More to the point, there was no mention of wire gauge in any of the P802.3ba objectives for copper cables either. Even for the optical interfaces with which I am more familiar, we only said “SMF” in the objectives, not IEC 60793-2-50 type B1.1, B1.3, or B6_A as we do in the standard.

 

Objectives tend to be rather high level directions, not things that nail down every possible corner of the solution space. For sure there might be solutions which meet the objectives that are not acceptable for any of various reasons. If someone proposes a solution that meets the letter of the objective but has some other undesirable characteristic (e.g., the cable is too fat, the connector is too large, whatever), we are all free to vote against adopting that proposed solution.

Regards,

Steve

 

From: Brad Booth [mailto:bjbooth@xxxxxxxxx]
Sent: Tuesday, May 31, 2011 1:00 PM
To: STDS-802-3-100GCU@xxxxxxxxxxxxxxxxx
Subject: Re: [802.3_100GCU] Successful May Interim

 

Chris,

 

My concern is about the objective. There is no mention of AWG in the twinax reach objective, even though it is probably fair to assume most people based their decision on 24 AWG.

 

Study groups have usually spent time trying to be specific when it comes to the UTP and optical cabling in reference to the reach. In this case, it may be useful to state that the 5m reach is based upon 24 AWG, because while the industry complains about its bend radius, it may be deemed acceptable for that reach. If the TF was to adjust the reach based upon using 24 AWG or decrease the gauge, then different criteria come into play and comments/ballots can be submitted accordingly.

 

It has been stated repeatedly in previous SG meetings is that the objectives are a contract with the WG about the work to be performed by the TF. It may be in the SG's and WG's best interest to ensure that there is good agreement on the gauge being assumed for a 5m twinax reach.

 

Cheers,

Brad

 

 

On Tue, May 31, 2011 at 10:10 AM, <CDimi80749@xxxxxxx> wrote:

Brad,

 

Please find responses inline....

 

Brad: If there is no information provided that indicates 24 AWG twinax copper cabling can meet the bend radius, diameter and weight requirements for inter-rack and intra-rack interconnect, then has the study group sufficiently responded to broad market potential?

 

Chris:

>>24 AWG twinaxial copper cables are used for inter-rack and intra-rack interconnects.

>>Although there are documents that address specifications for 24 AWG twinax copper interconnects related to bend radius, they don't constitute requirements for inter-rack and intra-rack interconnect applications.

>>For CX4, CR4 and CR10 the cable assembly differential characteristics are specified. During the development of these specifications, 24 AWG cable assembly measurements were presented.

>>In the formulation of the IEEE 802.3 100 Gb/s Backplane and Copper Study Group call for interest material, I provided outer dimensions for 24 AWG twinaxial cable - 9.3 mm (0.366).  

 

Regards, Chris

 

 

 

In a message dated 5/30/2011 10:50:28 P.M. Eastern Daylight Time, bjbooth@xxxxxxxxx writes:

John,

 

Glad to hear that the meeting was successful.

 

Was there any consideration for listing the gauge of the wire for the 5m twinax copper cabling objective?

 

At the meeting in Singapore, there was a request during the straw poll to list the gauge of wiring and it did slightly alter the results of the poll. Even the presentation by Mark Gustlin at last week's meeting highlighted the importance of bend radius and diameter which can be directly related to the gauge of wire. Did the study group discuss the bend radius and diameter requirements? Is it fair to assume that the gauge of wire for the twinax copper cabling objective is the same used in the Singapore straw poll (24 AWG)? If 24 AWG is assumed, was there any information presented or provided to indicate that the cable would be able to meet the bend radius, diameter and weight requirements for the intended application?

 

If there is no information provided that indicates 24 AWG twinax copper cabling can meet the bend radius, diameter and weight requirements for inter-rack and intra-rack interconnect, then has the study group sufficiently responded to broad market potential?

 

Thanks,
Brad

 

 

 

On Sat, May 28, 2011 at 11:39 PM, John D'Ambrosia <jdambrosia@xxxxxxxxxxxxxxx> wrote:

Dear Study Group Participants,

I hope everyone had safe journeys home.    I have to say it was one of my more adventurous travels.  However, given the success of the meeting, the travel was well worth it! 

 

The Study Group was successful in reaching consensus on the objectives, PAR, and 5 Criteria responses.  They have been posted, and may be found at http://www.ieee802.org/3/100GCU/index.html.

 

July will be the next key milestone, as we look forward to the necessary approvals to move from Study Group to Task Force. 

 

The minutes will be posted shortly.

 

Best Regards,

 

John D’Ambrosia

Chair, IEEE 802.3 100Gb/s Backplane and Study Group

 

 

 

 

 

 

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