[c-nsp] [OT] Driving 1310nm optics through 1550nm circulators

[Dale Shaw]

All,

On Jan 10, 2008 4:34 AM, David Freedman <david.freedman at uk.clara.net> wrote:
>
> > Interesting that his carrier delivers them as part of their *dark* fibre
> > product
>
> Perhaps its cheaper if you take a single strand + diplexer as opposed to
> a pair, (i.e perhaps its a "dark" single fiber and the diplexers are
> given to you for free if you want to use it for bidirectional
> communications) - personally I would ask if they sell dark pairs...

It's a co-operative, territory-wide Australian federal government
(dark fibre) network called ICON.

See: http://www.finance.gov.au/icon/

It was just easier to call it a 'dark fibre' service, since that
terminology will be familiar to most of you. It is neither cheaper or
more expensive, it's just the way it is.

It _is_ 'dark', but in parts of the network, particularly in and
around the city centre, there is a lot of contention for fibres. A few
years ago, ICON started delivering "circulators" at each end and using
a single strand between endpoints to conserve fibres. If a customer
wants both 1310nm and 1550nm wavelengths available, a WDM will be
installed as well. In practice, of course, I could plug whatever I
wanted into it, within the single-strand limitation -- I don't have to
use the "circulator" provided.

So, now that you all have the background, any tips re: my original query? :-)

cheers,
Dale