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Re: [802.3_100GCU] WebPage Updates



Conductors and construction are as important as insulator loss.
... Rich

-----Original Message-----
From: jgoergen [mailto:jgoergen@xxxxxxxxx] 
Sent: Friday, February 25, 2011 11:55 AM
To: Mellitz, Richard; STDS-802-3-100GCU@xxxxxxxxxxxxxxxxx
Subject: Re: [802.3_100GCU] WebPage Updates

Rich ... That doesn't make sense.

What is your issue?  I don't understand what you are trying to prevent?

joel


On 2/25/11 8:50 AM, "Mellitz, Richard" <richard.mellitz@xxxxxxxxx> wrote:

> I would suggest that we used "improved FR-4 fabrications" or "improved FR-4
> boards" so we don't solely on insulator material.
> ...Rich
> 
> -----Original Message-----
> From: Bhavesh Patel [mailto:Bhavesh_A_Patel@xxxxxxxx]
> Sent: Friday, February 25, 2011 10:21 AM
> To: STDS-802-3-100GCU@xxxxxxxxxxxxxxxxx
> Subject: Re: [802.3_100GCU] WebPage Updates
> 
> Joel, Agree that we should keep the wording 'improved FR-4' and then later
> define what it exactly means via electrical/mechanical properties.
> Bhavesh
> 
> -----Original Message-----
> From: jgoergen [mailto:jgoergen@xxxxxxxxx]
> Sent: Thursday, February 24, 2011 5:42 PM
> To: STDS-802-3-100GCU@xxxxxxxxxxxxxxxxx
> Subject: Re: [802.3_100GCU] WebPage Updates
> 
> John summed it well.  We can discuss a set of descriptors to be further
> detailed later in the study group, but I was hoping we could agree on the
> improved FR-4 and then define that more implicitly as part of the channel
> model and a study group presentation / discussion.
> 
> Take care
> -joel
> 
> 
> On 2/24/11 1:47 PM, "John D'Ambrosia" <jdambrosia@xxxxxxxxxxxxxxx> wrote:
> 
>> Bhavesh,
>> As I recall joel had provided a complete definition of the materials up to 15
>> ghz.  I would expect a similar type of definition with the appropriate
>> frequency range.
>> 
>> John
>> 
>> -----Original Message-----
>> From: Bhavesh_A_Patel@xxxxxxxx [mailto:Bhavesh_A_Patel@xxxxxxxx]
>> Sent: Thursday, February 24, 2011 4:12 PM
>> To: John D'Ambrosia; STDS-802-3-100GCU@xxxxxxxxxxxxxxxxx
>> Subject: RE: [802.3_100GCU] WebPage Updates
>> 
>> Does it makes sense to specify that 'improved FR4 ' needs to have Er & Df
>> below/above this limit @ particular frequency to meet channel criteria.
>> Bhavesh Patel
>> 
>> -----Original Message-----
>> From: John D'Ambrosia [mailto:jdambrosia@xxxxxxxxxxxxxxx]
>> Sent: Thursday, February 24, 2011 2:57 PM
>> To: STDS-802-3-100GCU@xxxxxxxxxxxxxxxxx
>> Subject: Re: [802.3_100GCU] WebPage Updates
>> 
>> Charles,
>> IMHO I think it is appropriate to specify what we intend to run over in the
>> objective, as well as then provide a definition of what that means.
>> 
>> John
>> 
>> -----Original Message-----
>> From: Charles Moore [mailto:charles.moore@xxxxxxxxxxxxx]
>> Sent: Thursday, February 24, 2011 3:53 PM
>> To: John D'Ambrosia
>> Cc: STDS-802-3-100GCU@xxxxxxxxxxxxxxxxx
>> Subject: Re: [802.3_100GCU] WebPage Updates
>> 
>> john,
>> 
>>      My point is a very minor one and was made badly.  Joel and i agree
>> that we do not want to imply that any FR-4 is going to work.  I want to
>> get the point across by not using the term FR-4 at all, joel wants to
>> get the point across by putting "improved" in.  I am a little concerned
>> that since the term was used in the ap objectives that it might be
>> construed to imply the amount of improvement to make ap work.
>> 
>>       It is really a matter of communication and which words express the
>> right idea to the largest number of people.  If a straw pole says
>> "improved FR-4" i will be happy to go along.
>> 
>>                                              charles
>> 
>> |--------------------------------------------------------------------|
>> |       Charles Moore
>> |       Avago Technologies
>> |       APD
>> |       charles.moore@xxxxxxxxxxxxx
>> |       (970) 288-4561
>> |--------------------------------------------------------------------|
>> 
>> 
>> 
>> John D'Ambrosia wrote:
>>> Charles,
>>> Please point out the definition "improved FR-4" in the IEEE specification.
>>> Ultimately, in IEEE 802.3ap the Study Group defined what that meant (well
>>> actually Joel, but it was approved by the Study Group).  This was done in
>>> order to assess whether the objectives were met.
>>> 
>>> If the definition had found its way into the specification I would be more
>>> inclined to support your point below.  However, it wasn't, and ultimately
>>> the
>>> informative channel model provided the attenuation / insertion that had to
>>> be
>>> targeted.  Then it is up to the implementer, who can use whatever material
>>> they choose.
>>> 
>>> Regards,
>>> 
>>> John 
>>> 
>>> -----Original Message-----
>>> From: Charles Moore [mailto:charles.moore@xxxxxxxxxxxxx]
>>> Sent: Thursday, February 24, 2011 3:11 PM
>>> To: STDS-802-3-100GCU@xxxxxxxxxxxxxxxxx
>>> Subject: Re: [802.3_100GCU] WebPage Updates
>>> 
>>> joel,
>>> 
>>>       Yes but.  We used "improved FR-4" to make 10GBASE_KR work.  We are
>>> going to need something better if we want to run 2.5x faster and
>>> 1.0-0.75x as far.  What can we call that?  Is it "more improved FR-4"?
>>> 
>>>                                                charles
>>> 
>>> |--------------------------------------------------------------------|
>>> |       Charles Moore
>>> |       Avago Technologies
>>> |       APD
>>> |       charles.moore@xxxxxxxxxxxxx
>>> |       (970) 288-4561
>>> |--------------------------------------------------------------------|
>>> 
>>> 
>>> 
>>> jgoergen wrote:
>>>   
>>>> Hi Charles
>>>> I get where you are going, but I am against removing the "improved fr-4" or
>>>> "enhanced fr-4" from any requirement.
>>>> 
>>>> My reasoning is that this implies all the channels we evaluate and the
>>>> standard we create are intended to run across fr-4 ... Which isn't true
>>>> from
>>>> my point of view.
>>>> 
>>>> Take care
>>>> -joel
>>>> 
>>>> 
>>>> On 2/23/11 9:44 AM, "Charles Moore" <charles.moore@xxxxxxxxxxxxx> wrote:
>>>> 
>>>>   
>>>>     
>>>>> paul,
>>>>> 
>>>>> I looked at the objectives for 802.3ba and kind of liked the wording
>>>>> there. Cribbing from it, how about:
>>>>> 
>>>>> Provide Physical Layer specifications which support 4-lane 100 Gb/s
>>>>> operation over:
>>>>> * at least Xm over a copper cable assembly
>>>>> * at least Ym over a backplane
>>>>> 
>>>>> This sidesteps the issue of defining "improver FR4", something which we
>>>>> carefully avoided defining in 802.3ap. If we do use the term "improved
>>>>> FR4", the actual definition will only come after we write a channel
>>>>> spec. Then "improved FR4" is defined as any fire retardant material
>>>>> which will allow you to build a compliant channel Ym long.
>>>>> 
>>>>> charles
>>>>> 
>>>>> |--------------------------------------------------------------------|
>>>>> |       Charles Moore
>>>>> |       Avago Technologies
>>>>> |       APD
>>>>> |       charles.moore@xxxxxxxxxxxxx
>>>>> |       (970) 288-4561
>>>>> |--------------------------------------------------------------------|
>>>>> 
>>>>> 
>>>>> 
>>>>> Kolesar, Paul wrote:
>>>>>     
>>>>>       
>>>>>> John,
>>>>>> 
>>>>>> Thanks for posting your planned co-authored contribution on
>>>>>> objectives. As you said, this contribution proposes the form of the
>>>>>> objectives and leaves the key parameters open. I have previously
>>>>>> commented to this forum about a particular form that, while apparently
>>>>>> approved in the past, is illogical, conflicting and ambiguous because
>>>>>> it mixes words that define minima with words that define maxima.
>>>>>> Specifically, slide 4 states the reach requirements using the phrase
>>>>>> ³up to at least X m². One can take this to define a maximum of X m
>>>>>> (i.e. ²up to²) or a minimum of X m (i.e. ³at least²). Given this
>>>>>> conflict the only logical interpretation that can simultaneously meet
>>>>>> both is a reach of _exactly_ X m. I do not find this acceptable and
>>>>>> have previously proposed to state these objectives clearly as minima
>>>>>> using the non-conflicting phrase ³of at least X m². This will avoid
>>>>>> some problems that have occurred in the past with interpretation when
>>>>>> the value of X was challenged.
>>>>>> 
>>>>>> I also do not understand the utility of the phrase ³consistent with².
>>>>>> It appears to be a way to interject some flexibility. But I do not
>>>>>> have an appreciation for what that implies. Perhaps someone could
>>>>>> enlighten me. Without that insight I would further simplify the form
>>>>>> to the following.
>>>>>> 
>>>>>> Define a 4-lane 100 Gb/s PHY for operation over copper traces on
>>>>>> 
>>>>>> ³improved FR-4² for link lengths of at least ³X² m.
>>>>>> 
>>>>>> Define a 4-lane 100 Gb/s PHY for operation over copper twin-axial
>>>>>> 
>>>>>> cables for link lengths of at least ³Y² m.
>>>>>> 
>>>>>> Regards,
>>>>>> 
>>>>>> Paul Kolesar
>>>>>> 
>>>>>> ------------------------------------------------------------------------
>>>>>> 
>>>>>> *From:* John D'Ambrosia [mailto:jdambrosia@xxxxxxxxxxxxxxx]
>>>>>> *Sent:* Wednesday, February 23, 2011 2:07 AM
>>>>>> *To:* STDS-802-3-100GCU@xxxxxxxxxxxxxxxxx
>>>>>> *Subject:* [802.3_100GCU] WebPage Updates
>>>>>> 
>>>>>> All,
>>>>>> 
>>>>>> This email is to inform you of two updates to the Study Group Web Pages.
>>>>>> 
>>>>>> First, Mark Bugg has provided a calibration file, which will allow
>>>>>> de-embedding of the board traces. This file may be found at
>>>>>> 
> 
http://www.ieee802.org/3/100GCU/public/ChannelData/Molex_11_0210/2XCAL.zip>>>>>
>
> .
>>>>>> My thanks to Mark for providing this file.
>>>>>> 
>>>>>> Next, as discussed at our prior meeting, the SG needs to focus on
>>>>>> setting its objectives. To that end I have worked with Howard Frazier
>>>>>> and Adam Healey on a presentation (see
>>>>>> http://www.ieee802.org/3/100GCU/public/mar11/dambrosia_01_0311.pdf) to
>>>>>> discuss objectives for the project. We have proposed the forms of
>>>>>> several objectives (leaving the important details as TBDs). I would
>>>>>> ask that everyone review this presentation, and consider how the
>>>>>> presentation that they plan to submit will contribute to helping us
>>>>>> determine our objectives. This presentation is only intended as an
>>>>>> initial list of key objectives.
>>>>>> 
>>>>>> Regards,
>>>>>> 
>>>>>> John
>>>>>> 
>>>>>>       
>>>>>>         
>>>>   
>>>>