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a.sun
on the chip level, some think Si photonics optoelectronic chips are treated ...
a.sun
I think the battle of standards is in form factor. Both Cisco and Intel rolled ...
Kotura preps fab deal amid silicon photonics surge
Rick Merritt
1/25/2013 9:01 AM EST
For all the promise, silicon optics at 100G faces a boat load of challenges.
To start with, there are no standards, something that’s typically a requirement for anyone specifying Ethernet. The IEEE 802.3bm group is working on low-cost 100G Ethernet standards for the data center, but the work is at an early stage.
Standards would be handy given the diverse architectures emerging—and this is about networking where interoperability is a requirement. Vendors expect to sell what they have in 2014 and hope the standards work goes their way.
The VCSELs used in today’s optics remain competitive. Vendors are showing 25G products today and prototypes of 40+G products, including ones that support multiple wavelengths, said Michael Krause, an interconnect expert at Hewlett-Packard.
“Dramatic cost reductions as measured in dollars per Gbit per meter have enabled VCSELs to be cost-effective across multiple market segments including consumer use via active cables,” said Krause. “My personal view is the advent of 10 Gbit USB will provide a significant boon to VCSEL-based optical active cable solutions and help drive further cost reductions that will benefit the entire spectrum of product offerings.”
Demand for ultra high bandwidth links is smaller than many realize, Krause added. Today gigabit Ethernet serves the majority of servers and 10G is just beginning to move into the mainstream. In addition, most chips are too constrained by memory bandwidth and a lack of pins to be able to use 100G network links, he said.
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resistion
1/25/2013 10:54 PM EST
It looks like a lot of parallelism is needed for any electronics to match 100G/s.
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a.sun
1/29/2013 2:05 AM EST
First of all, it is not to be confused with 100G used in telecom which used advanced modulation to achieve serial 100Gb/s. It's for datacom 100G which can be 10x10Gb/s or 4x25Gb/s, the former was adopted earlier but slower and seems being replaced by the latter as 25G electronics are getting ready. Most early advocates of 10x10G shifted to 4x25G now. No matter for telecom 100G or for datacomm 100GBASE, no 100Gb/s electronics is actually used or needed.
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eastlau
1/26/2013 1:48 AM EST
Wonderful article! What do you refer to by " there are no standards"? 100G standard is more mature than 40G, e.g. PM-QPSK modulation is the only one adopted in 100G,while there is no standard modulation method in 40G.
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eastlau
1/26/2013 2:02 AM EST
How about the 100G standard for optical network?
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rick.merritt
1/28/2013 12:43 PM EST
I meant there are no standards specifically for silicon photonics
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a.sun
1/29/2013 12:21 PM EST
I think the battle of standards is in form factor. Both Cisco and Intel rolled out their own connectors to compete with existing MPO connector for highly parallel optics. Intel and IBM&Avago even wanted to completely eliminate all current panel mount transceivers module such as QSFP+, CFP, etc. which is a big threat to many component&module suppliers. We'll see how it goes.
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a.sun
1/29/2013 12:27 PM EST
on the chip level, some think Si photonics optoelectronic chips are treated unfairly as all the standards are written in accordance to III-V materials. Some of these standards may not be absolutely necessary for use in practice. It's why most Si photonics products are used in AOC which only have end-to-end electrical specs. Hopefully big players like Intel, IBM can change it.
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yazhouren
1/28/2013 9:45 PM EST
牛x
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