On CNET: Update software safe and spyware free
BNET Business Network:
BNET
TechRepublic
ZDNet
TalkBack 30 of 33:
Next »
« Previous
Modern Fiber cables use solid state amps
Again from Wikipedia - http://en.wikipedia.org/wiki/Submarine_communications_cable

"In the 1980s, fibre optic cables were developed. The first transatlantic telephone cable to use optical fibre was TAT-8, which went into operation in 1988.

Modern optical fiber repeaters (1990s) use a solid-state optical amplifier, usually an Erbium-doped fiber amplifier. Each repeater contains separate equipment for each fibre. These comprise signal reforming, error measurement and controls. A solid-state laser dispatches the signal into the next length of fiber. The solid-state laser excites a short length of doped fiber that itself acts as a laser amplifier. As the light passes through the fibre, it is amplified. This system also permits wavelength-division multiplexing, which dramatically increases the capacity of the fiber."

The early fiber optic cables required optical to electrical conversion, then amplification, then re-conversion from electrical back to optical. These cables had some latency issues. I don't know the numbers, but had to be somewhat of an issue. Realize that Satellite circuits also have real latency issues, particularly on multi-Sat hops. We see this all the time on overseas TV news interviews.

But with the introduction of the EDFA amps, it is light all the way with no O/E conversions involved. It's light in, amplified, and light out (like magic). So, today, latency is not much of an issue.
Posted by: K1FDH   Posted on: 04/11/08 You are currently: a Guest | Members login | Terms of Use
Reply to Story Reply to Message

Alert moderator to an offensive message

Subscribe to this discussion via Email or RSS

Physical Compression  Dr_Zinj | 04/09/08
Treated?  jhurst747 | 04/09/08
That's the expensive way...  JohnMcGrew@... | 04/09/08
RE: (Photos: Australia's 5,500-mile Internet connection)  chris752 | 04/09/08
RE: (Photos: Australia's 5,500-mile Internet connection)  vulcan96 | 04/09/08
RE: (Photos: Australia's 5,500-mile Internet connection)  vulcan96 | 04/09/08
They are called "Notice to Mariners"  Michael P. | 04/09/08
What does Australia use now? Satellite?  meryllogue@... | 04/09/08
They use other existing cables...  UncleBubba | 04/09/08
RE: (Photos: Australia's 5,500-mile Internet connection)  maxtheitpro | 04/09/08
RE: (Photos: Australia's 5,500-mile Internet connection)  stewpeake | 04/09/08
Australia and . . . . Hawaii??  CobraA1 | 04/09/08
AZ to Hawaii just part of global network  K1FDH | 04/11/08
Here's the link to Int'l. submarine cables  K1FDH | 04/11/08
RE: (Photos: Australia's 5,500-mile Internet connection)  paul351 | 04/09/08
another reason  seanferd | 04/09/08
RE: (Photos: Australia's 5,500-mile Internet connection)  blackjack861@... | 04/09/08
Pure science vs. entertainment etc.  boomchuck1 | 04/10/08
Toil and Sacrifice  Methushelah | 04/10/08
What microscope are we supposed to use  mhenriday | 04/11/08
Relevance  Methushelah | 04/24/08
Idiot  bigjohnt@... | 04/12/08
RE: (Photos: Australia's 5,500-mile Internet connection)  leanne_martinau | 04/10/08
Powering the amplifiers?  bbbaldie_z | 04/10/08
Probably still electric?  Kev Baylis | 04/10/08
RTFM  Kev Baylis | 04/10/08
High voltage DC still used  K1FDH | 04/11/08
Has anyone seen any video posted?  clare_smith@... | 04/10/08
Latency  brittonv | 04/10/08
Modern Fiber cables use solid state amps  K1FDH | 04/11/08
RE: (Photos: Australia's 5,500-mile Internet connection)  Kapukini | 04/14/08
RE: (Photos: Australia's 5,500-mile Internet connection)  NZJester | 04/16/08
WIRED covered this many years ago:  gbdrbob | 07/15/08

What do you think?

SponsoredWhite Papers, Webcasts, and Downloads

advertisement
advertisement