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Hello Jeff
I?ll see what I can do to provide some information.
Regards, John
From: Jeffery Maki [mailto:jmaki@xxxxxxxxxxx]
John,
I asked a simple question. What is the cost delta?
I heard Jonathan indicated a 10% reduction in cost for the line item of per-module test time between the use and non-use of FEC.
What is the cost delta for the transmitter, if any?
What is the cost delta for the receiver, if any?
Jeff
From: John Petrilla [mailto:john.petrilla@xxxxxxxxxxxxx]
Hello Jeff
Once a PMD is defined such that it permits the lowest cost power and size, it will be possible, where there?s interest, to add features or support premium versions without asking those satisfied with the lowest cost power and size version to subsidize the cost of additional performance.
Regards, John
From: Jeffery Maki [mailto:jmaki@xxxxxxxxxxx]
John,
The assumption of the use of FEC has to be explicit so all know that it must be implemented and so that they know that the latency of FEC will occur. Is FEC really so important to the technical proposal so at to justify it? Cost reduction of FEC would be one metric for its justification.
The issue then turns to market acceptance of FEC latency. For 500 meters, one might argue 802.3bj FEC latency is not an issue. As the reach goes down, the relative contribution of the FEC latency increases in terms of the overall link latency (time of flight of light in glass). Please keep in mind also that absolute link latency is a market differentiating variable. I?d like to see market acceptance of FEC latency presented as a function of reach for optical links. (Just because the 802.3bj task force adopted an FEC with a certain amount of latency does not mean we get to stop thinking in the 802.3bm task force about our own market acceptance of FEC.)
Jeff
From: John Petrilla [mailto:john.petrilla@xxxxxxxxxxxxx]
Hello Jeff
Unfortunately, justification of the 500m SMF objective for the project is explicitly cost, size and power. While I can sympathize with other with other issues, I would need a lot of help explaining why cost, power or sized was sacrificed.
Regards, John
From: Jeffery Maki [mailto:jmaki@xxxxxxxxxxx]
All,
We have to make sure that the assumption of the use of FEC is explicit. Although we might argue not to count the cost of the FEC encoder/decoder itself, we do need to understand the impact on cost that the use or lack of use of FEC poses. It is good thus to make analysis of the impact on cost of designs presuming the use of FEC versus designs presumed NOT to use FEC. I see the potential lack of need of FEC as one of the technical advantages of parallel single mode as well as market-acceptance advantages.
Jeff
From: Anslow, Peter [mailto:panslow@xxxxxxxxx]
Hi,
As previously announced, there is an SMF Ad Hoc meeting starting at 8:00 am Pacific today Tuesday 18 December. I have currently received two requests for presentations, so the draft agenda is:
· IEEE patent policy reminder o http://www.ieee802.org/3/patent.html
· Approval of the draft minutes from 4 December call
· Presentation o PSM4 Technology & Relative Cost Analysis Update Jon Anderson, Oclaro o Basic Study on Receiver Bandwidth Requirement for Discrete Multi-tone Modulation Masato Nishihara, Fujitsu
· Discussion
· Future meetings (next opportunity - 8 Jan)
I hope to post both presentations on the SMF Ad Hoc web page just prior to the meeting.
Peter Anslow from Ciena has invited you to join a meeting on the Web, using WebEx. Please join the meeting 5-10 minutes early so we may begin on time. +44-203-4333547 (United Kingdom) 4438636577 (United States)
Regards, Pete Anslow | Senior Standards Advisor
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