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
>>>>>
>>>>>
>>>>>
>>>
>>>