Dan,
I agree with you that this requires a thoughtful offline discussion and
well articulated guidelines.
The perfect world you describe is unfortunately far removed from
reality. PCB type, number of components, etc are not what drives cost
differences. It is ASICs, lasers, fibers, test, and assembly. One
example comparison from 802.3ba is illustrative: 10G DFB lasers vs. 40G
EML. How do you determine their relative costs in a perfect world?
Chris
-----Original Message-----
From: Daniel Dove [mailto:ddove@xxxxxxx]
Sent: Friday, February 03, 2012 3:48 PM
To: Chris Cole
Cc: STDS-802-3-100GNGOPTX@xxxxxxxxxxxxxxxxx
Subject: Re: [802.3_100GNGOPTX] Minutes Uploaded - Forward Direction
Hi Chris,
I also do not want to rely upon my own interpretation and have requested
an opinion from David Law.
In my perfect world, someone would present an analysis on relative cost
of X vs Y using size, PCB type, thickness, number of comparable
components, processing differences, die size, power, and the like to
come to a relative cost between X and Y.
They would present that at the meeting. People would either nod their
heads and agree, or they would challenge assertions and perhaps not come
to consensus. Consensus does not mean everyone having the same numbers,
it means everyone nodding their head and agreeing that the analysis is
"close enough for engineering". Consensus might be that the presenter
was off on their numbers, and more presentations would have to come in
to get consensus.
Once that had been done, others could compare Z's relative cost to
either X or Y and the group would now have a feel for how X, Y and Z
stack up.
I am just not comfortable taking "cost" based on market information.
That is not cost IMHO.
Lets put a damper on this discussion until David Law can provide his
opinion.
Dan
On 2/3/12 3:33 PM, Chris Cole wrote:
Steve,
You have fully captured the difficult problem we face in trying to do
due diligence on competing proposals.
If we use completely sanitized solution A and solution B costs which
cannot be referenced to more generally available data, then we are
back
to "liar's poker" or more generously to "he said, she said". In that
case, there is no way to challenge the cost assertions of proponents
of
solution A or solution B.
If on the other hand we use more generally available data, so that
there
is objectivity in the cost comparisons, not just unsubstantiated
claims,
then this can always be traced to an actual dollar amount even if
through a tortuous path.
So the concern I raised about not being able to demonstrate 5
Criteria,
as further commented on by Brad, is genuine.
The solution we employed in 802.3ba is to use cost numbers averaged
over
many suppliers and many variants. In practice there is a very wide
variability in the market around that baseline, and the specific
average
number may not even exist. The information is equally available to
everyone so it does not confer an advantage on any party in the
market.
Despite all this, it is obviously not as crisp as not using any
generally available relative cost data.
We are going to have to agree to some more useful guidelines than have
been given so far if we don't want to rely on ad hoc interpretations
by
the chairs of every email or presentation.
Chris
-----Original Message-----
From: Trowbridge, Stephen J (Steve)
[mailto:steve.trowbridge@xxxxxxxxxxxxxxxxxx]
Sent: Friday, February 03, 2012 2:06 PM
To: STDS-802-3-100GNGOPTX@xxxxxxxxxxxxxxxxx
Subject: Re: [802.3_100GNGOPTX] Minutes Uploaded - Forward Direction
Hi Chris,
I think that a lot of folks on the list are having trouble
distinguishing the difference in the meaning of "price" and "cost",
but
also about the meaning of the word "relative".
If people start describing costs relative to something they can buy
today, and everybody knows the price of what they can buy today,
people
assume that if the same margins were to apply, they can infer a
relative
price. This gets dangerous in that you are essentially deciding "how
big
is a banana", and then using bananas as currency.
The idea of "relative" to my understanding is that you need to
restrict
yourself to "A" vs. "B" comparisons, and not put the universe on a
common scale which amounts to defining a currency which basically
translates to price. So if you have two ways to solve a problem, you
can
compare the relative costs of those two solutions. If you are trying
to
test if a "replacement" PMD is justified, you would want to analyze
the
long term cost of what is inside of the module to see if that looks to
cost enough less, long term, to be worth building.
What I see people trying to do is to establish this currency where
folks
are asked to compare their own proposal to some baseline (e.g., SR10)
assuming that if everyone uses the same baseline, you can do
arithmetic
and effectively compare the relative costs of solution A vs solution
B,
not by actually comparing them directly against each other, but by
using
some other established currency. I am not sure this is a really
productive exercise either, since I think it would just create a game
of
"liar's poker" with every contributor trying to construct a story that
puts their solution at the lowest "cost" based on this common
currency.
This assumption is wrong unless you can guarantee that everyone who
does
this is equally thorough, equally honest, equally optimistic (or
pessimistic). The common scale won't help you: you really need to look
at solutions directly against each other.
Regards,
Steve
-----Original Message-----
From: Chris Cole [mailto:chris.cole@xxxxxxxxxxx]
Sent: Friday, February 03, 2012 2:35 PM
To: STDS-802-3-100GNGOPTX@xxxxxxxxxxxxxxxxx
Subject: Re: [802.3_100GNGOPTX] Minutes Uploaded - Forward Direction
John
Can you explain the difference between the discussion of relative
module
costs in NG 100G OE SG, and the discussion of relative module costs in
HSSG and 802.3ba including of specific form factors?
Chris
-----Original Message-----
From: John D'Ambrosia [mailto:jdambrosia@xxxxxxxxxxxxxxx]
Sent: Friday, February 03, 2012 1:14 PM
To: STDS-802-3-100GNGOPTX@xxxxxxxxxxxxxxxxx
Subject: Re: [802.3_100GNGOPTX] Minutes Uploaded - Forward Direction
Dan,
Let me clear - do not include me on any discussions regarding price.
That is an inappropriate discussion and I do not want to be involved!
John
-----Original Message-----
From: Daniel Dove [mailto:ddove@xxxxxxx]
Sent: Friday, February 03, 2012 4:11 PM
To: STDS-802-3-100GNGOPTX@xxxxxxxxxxxxxxxxx
Subject: Re: [802.3_100GNGOPTX] Minutes Uploaded - Forward Direction
Seriously, folks;
I am going to officially ask that if you wish to talk about products
and
their relative prices, please do it on a different discussion forum.
Maybe an email thread among friends?
We are here to talk about IEEE standards, PMDs, and their relative
costs.
Dan Dove
Chair, Next Generation 100G Ethernet Study Group