RE: Silicon-germanium routers?
I also suspsect that the community is not ready to transition to liquid-cooled systems. I rather assumed 'at room temperature' implied a standard heat sink and fan. Perhaps there's not enough information in that article to draw a conclusion from. There are a few bits that folks should understand: first, SiGe has been around for awhile. It's not new. It's used when higher frequencies are necessary, such as when building a 40Ghz modulator for an OC-768c interface. SiGe is more expensive, less thermally efficient, and less dense than 'standard' CMOS. So it's already headed the wrong way for most of our applications. Second, you should know that there are lots of folks who really are experimenting with a single transistor. This may sound ludicrous, but the thought here is that process improvements will eventually scale. Thus, the conclusion that I'm leaping to is that this room temperature transistor at 350GHz really is at room temp, but may require something like a muffin fan all by itself. Obviously to scale that to a few hundred million transistors in a router, you then need a few hundred million little fans. ;-) The breakthrough that we're looking for is a high speed, high density, low power transistor that can be commercially scaled with good yield. Not there quite yet. Tony
Re: Silicon-germanium routers?
On Jun 20, 2006, at 11:11 PM, Tony Li wrote: The breakthrough that we're looking for is a high speed, high density, low power transistor that can be commercially scaled with good yield. Not there quite yet. In comparison to early-80s ECL, how do you think the scaling curve might match? I haven't found much material yet that shows any realistic projections for speed and yield ramp up for the new stuff. --lyndon
RE: Silicon-germanium routers?
IBM and Georgia Institute of Technology are experimenting with silicon- germanium, it is said here: http://tinyurl.com/g26bu I find this interesting having just attended NANOG 37 where some manufacturers of network devices told us in a panel that network heat problems weren't going away unless there's a 'next big thing' in manufacturing process. Is this it? Sure doesn't sound like it. In fact, it sound like they're pushing to a high frequency regardless of the power and thermal consequences. It also sounds like it's a single transistor. It takes a few of them to make a router. ;-) I also suspsect that the community is not ready to transition to liquid-cooled systems. Tony
Re: Silicon-germanium routers?
David W. Hankins wrote: IBM and Georgia Institute of Technology are experimenting with silicon- germanium, it is said here: http://tinyurl.com/g26bu I find this interesting having just attended NANOG 37 where some manufacturers of network devices told us in a panel that network heat problems weren't going away unless there's a 'next big thing' in manufacturing process. Is this it? Corrolary: If our routers are made of silicon-germanium, would the CLI only operate in Deutsch? Jawoll, es wuerde :) I remember my old radio days. My audion and diode receivers never would work with silicon only with germanium diodes and transistors. The difference is the voltage threshold where the device would start conducting. That is 200 mV for germanium but 800 mV for silicon. Devices running with silicon and 2.4 volts will go down to 600 mV. That means power consumtion will drop to 1/4. The real thing is a bit more complex but for a guesstimation ... Cheers Peter and Karin -- Peter and Karin Dambier Cesidian Root - Radice Cesidiana Graeffstrasse 14 D-64646 Heppenheim +49(6252)671-788 (Telekom) +49(179)108-3978 (O2 Genion) +49(6252)750-308 (VoIP: sipgate.de) mail: [EMAIL PROTECTED] mail: [EMAIL PROTECTED] http://iason.site.voila.fr/ https://sourceforge.net/projects/iason/
Re: Silicon-germanium routers?
On Jun 20, 2006, at 12:18 PM, David W. Hankins wrote: IBM and Georgia Institute of Technology are experimenting with silicon- germanium, it is said here: http://tinyurl.com/g26bu I find this interesting having just attended NANOG 37 where some manufacturers of network devices told us in a panel that network heat problems weren't going away unless there's a 'next big thing' in manufacturing process. Is this it? Nope, all this says is that with sufficient cooling you can go faster. What we need is going faster with less cooling. W Corrolary: If our routers are made of silicon-germanium, would the CLI only operate in Deutsch? -- David W. HankinsIf you don't do it right the first time, Software Engineer you'll just have to do it again. Internet Systems Consortium, Inc. -- Jack T. Hankins -- A. No Q. Is it sensible to top-post?
Re: Silicon-germanium routers?
Once upon a time, Warren Kumari [EMAIL PROTECTED] said: Nope, all this says is that with sufficient cooling you can go faster. What we need is going faster with less cooling. Read the article, not the headline. They got 350GHz at room temperature (which is a lot more interesting than 500GHz a few degrees above absolute zero). -- Chris Adams [EMAIL PROTECTED] Systems and Network Administrator - HiWAAY Internet Services I don't speak for anybody but myself - that's enough trouble.
Re: Silicon-germanium routers?
On Tue, Jun 20, 2006 at 12:59:54PM -0700, Tony Li wrote: Sure doesn't sound like it. In fact, it sound like they're pushing to a high frequency regardless of the power and thermal consequences. I thought their 500 Ghz number was just for rediculous press teasing, like the people who use lHe to push AMD chips to ~10 Ghz. The 350 Ghz 'at room temperature' insinuation is the most interesting to me. It also sounds like it's a single transistor. It takes a few of them to make a router. ;-) I haven't seen any evidence to support or contradict this, so I'll take your word for it... A single-transistor test on a single chip would be both ludicrous and incomparable. I also suspsect that the community is not ready to transition to liquid-cooled systems. I rather assumed 'at room temperature' implied a standard heat sink and fan. Perhaps there's not enough information in that article to draw a conclusion from. -- David W. HankinsIf you don't do it right the first time, Software Engineer you'll just have to do it again. Internet Systems Consortium, Inc. -- Jack T. Hankins pgptLk0mecD4k.pgp Description: PGP signature
Re: Silicon-germanium routers?
The point that I was trying to make (admittedly REALLY badly) was that this is not the 'next big thing' . Did you read anything more than just that article? IBMs press release is here: http://www-03.ibm.com/technology/news/2006/0620_frozen_chip.html and they have a video here: http://www-03.ibm.com/technology/ets/capabilities/multimedia_tour/ frozen_chip_wmv.html This is not a new technology (IBM shipped their 100 millionth SiGe chip in around 2002 and if you look at the SONET chipset on an OC48 or greater interface chances are its SiGe), but the speed in cheap material is (Feng Hafez achieved 600Ghz in indium doped) -- this is primarily just a bragging right though. It requires liquid helium temperatures, something that is not practical in the near term, and requires a LOT of power to achieve. On Jun 20, 2006, at 2:05 PM, Chris Adams wrote: Once upon a time, Warren Kumari [EMAIL PROTECTED] said: Nope, all this says is that with sufficient cooling you can go faster. What we need is going faster with less cooling. Read the article, not the headline. They got 350GHz at room temperature (which is a lot more interesting than 500GHz a few degrees above absolute zero). Yes -- the previous silicon based speed record *at room temp* was 375Ghz. Warren -- Chris Adams [EMAIL PROTECTED] Systems and Network Administrator - HiWAAY Internet Services I don't speak for anybody but myself - that's enough trouble. -- Have you got any previous convictions? Well, I dunno... I suppose I used to believe very firmly that a penny saved is a penny earned-- -- Terry Pratchett
