At 12:36 PM -0700 7/12/02, Scott Granados wrote:
Actually, research has been done that uses rare gasses to slow and even stop the photons down in a tube. It would be possible to store the states of photons in these tubes and then release them when you wanted with out requiring miles of fiber.
That process requires a reference beam, and currently can only be tuned for specific wavelengths. Decoherence also occurs fairly rapidly in the system. In a DWDM network, you would need as many units as there are wavelengths in order to do a full capture. http://www.sciencenews.org/20010127/fob1.asp Given how fast this field is moving though, it may become practical sooner rather than later.
Also, photons work in pairs. It may be possible to split the pairs on the fiber and observe the actions in the fiber remotely by capturing one side of the pair and allowing the others to continue. They interact in pairs even though physical distance is between them.
I think you may be thinking about quantum-entangled pairs. That phenomena is better suited to cryptography than general networking. In an entangled system, both recipients would know pretty quickly that they did not receive their photons as there would be an early 'measurement' on one end, and a missing photon on the other.
On Fri, 12 Jul 2002, Chris Kilbourn wrote:
At 2:32 PM -0400 7/12/02, Ralph Doncaster wrote:
Add in the fact that optical sniffing, while not impossible by any means today, will increasingly become non-trivial as bandwidth increases. Which is exactly one of the 'problems' they expect optical network to solve.
You mean just expensive, right? i.e. a couple transponders and an OC48 or OC192 switch.
Cost is a factor, certainly, but the storage of the captured data becomes the larger problem.
In the TB or PB range of optical data transmission, where and how do you store the captured information? Unless you have TB's of solid state drives to stream electrons into after an optoelectronic photon -> electron conversion your only other option is to store the photons in loops of fiber with an optical repeater.
Until we have quantum computers which might be able to parse the data in real-time, we still need a buffer to store the data in before we can look for the needle in the haystack.
Even with some nifty filtering on the sniffer, you're potentially looking at obscenely large amounts of information to store.
I would expect that the distance of fiber you will need to store the data in will be the gating factor, which means it tilts more towards a physical issue than a cost issue.
If I need a few thousand kilometers of fiber as a storage loop, it's kind of hard to move around efficiently. :-)
Regards, Chris Kilbourn Founder _________________________________________________________________ digital.forest Int'l: +1-425-483-0483 where Internet solutions grow http://www.forest.net