Sector, Daniel, Robert, and All,
What a bunch of questions. Wow. First the inquiry about the MRVC claims concerning "dynamic DWDM," and then:
>>Who else has Optical Switching and routing, et al at this time?... Who is working on it?...Who is close? <
Before I attempt to get into those questions head on... second thought, maybe I wont go there today... this lexicon is beyond the point of stress and strain from overuse, and under-specificity.
For the past three years we've been patiently watching and waiting as the word smiths and pundits made their hay by debating the merits of Companies' a, b and c's different approaches to Switching at Layer 3, Routing at Layer 2, Routing at Layers 4 and 5 "via silicon switching" of heretofore software routed flows, and so on. At the code level, if you could ever get your hands on it, it made sense. But from the marketecture standpoint, it's been annoying, sometimes very misleading, and always unbearable to watch the sales guys and gals tell it the way they did.
When we get down to it, routing and switching are meaningless words in many instances, when they are used in historical contexts. Maybe some day CSCO or LU will write an RFC designed to clear the air of the entire affair. Nahhh... never happen.
Now we have a situation where the most fundamental of modern day media, an optical fiber strand, which is a Layer One Network Element, is undergoing subdivisions in basic utility, and being redefined as to its capabilities in a new set of sub-Layer 1 routing and switching categories.
I recently asked someone who is doing a tutorial for some IETF committee event, what happens when Tag Switching at Layer 3 of the Original OSI model took place over an optically routed lambda path. All I was told was that this doesn't happen. <!?!> Come on guys, you've gotta laugh with me on this one. It's the truth, though.
Where convergence sublayers were once something that came from above, they are now from beneath. And we continue to use the terms routing and switching in both cases with impunity, as though they still maintained the same definitions in taxonomy.
Now, the foregoing several paragraphs have very little bearing on the subject at hand, and only marginal merit in fact, but I thought that I'd throw them up on the screen for the hell of it.
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As for the MRVC press release, here we go again with one of my pet peeves.
I don't even know which one of the MRVC companies that product is made by. I don't like the release the way it was written, and I can't find anything that substantiates the claims in any specifications on any of their web sites. Whew. There, I've said it again.
The only web address-related thing I can find on the PR is an email address that goes to nBase. I go there and I find a bunch of LAN articles, white papers, but nothing obvious that I could discern on dynamic DWDM. Before I go on about this, maybe Robert, who asked the original question, can point me to a URL that speaks to this product in more definitive terms. How about it Robert? Can you give me a hand here?
As for optical routing in general, there are all sorts of things taking place right now in labs, from temperature-modulated "mirror" excitation, to electronic payload mapping at the static lambda interface, and much more. I'm lost as to which approach is in the lead, which ones are already abandoned, and what is coming out of the shoot next. As to who is doing allof this, you can rest assured that grants have flooded the universities, the top tiered DWDM companies are all into it either internally, or aided by consulting and university assistance, and some of the emerging multi-gigabit and terabit router companies are also getting their feet wet in the optical domain.
Maybe Ray Jensen, who's been very quiet [and missed] here lately, can jump in and pick up some of this slack.
For some discussion on this topic that will convince you that it is not a subject borne out of trivialities, go to the following Lightwave Magazine article that addresses one such approach. I think you'll enjoy it, or at least get a sense of why I don't want to go there today.
Here's the URL, and an excerpt of the article that touches on the meat of the matter, immediately following.
Enjoy, and Regards, Frank Coluccio
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broadband-guide.com:80/lw/news/news2984.html
Excerpt begins:
Optical switching technology, in the form of lithium-niobate
cross-bar switches, is fairly well developed. (Unlike electronic
switches, it has proven easier to build optical switches with high
throughput than with high dimensionality.) In the system
demonstrated, these devices are switched using electrical pulses.
Optical-signal processing associated with switching avoids the
data flow bottleneck at the input to the photonic switch and
reduces the need for flow control. The researchers report, "We
have demonstrated ultrafast optical flow control using a recently
developed Terahertz Optical Asymmetric Demultiplexer," also
called toad. The device can demultiplex a picosecond time-slot
from a nanosecond address-frame. It requires less than one
picojoule of switching energy and can be made small enough to be
integrated onto a chip.
In ultrahigh-speed optical networks, address bits in a compressed
packet are spaced only picoseconds apart. To read the address
bits, ultrafast demultiplexers (such as the toad) are used, one to
read each address bit in the packet header. This address
information is used by the routing controller to set the switch.
The researchers demonstrated the optical routing using a network
of 2 x 2 lithium-niobate cross-bar switches, an ultrafast all-optical
address recognition unit (which decodes the destination address),
a routing controller (which sets the state of the switching element),
and an optical buffer that matches the delay of the input packets to
the processing delays of the routing controller.
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