Long distance fiber question.

I know some folks here deal with long distance fiber so I thought someone can sanity-check this one for me.

Here's the background. Our IT has spare fiber available which I would like to use. However, they said they can't simply assigned them to be because

"Because the distance (~12 miles), special equipment is needed to do the transport and we have to supply those equipment, also, these are *special* fibers that your off the shelf stuff can't handle"

I really, really, really don't want part of the path be under the ownership of IT for obvious reasons. I did a bit of searching and it seems there are plenty of fiber converter or SFP that can handle that distance. I also very doubtful about these "special" fiber claims.

Can someone shed some light on the claims?

It is possible that it is a different type of fiber than what you are accustomed to dealing with. Most shorter run fiber is multi-mode fiber. It's a thicker fiber and light can take multiple different paths down the fiber to reach the other end. Longer run fibers tend to be single-mode fiber. It's thinner and does require different equipment to interface.

According to them, it's not SM or MM, it's "special"... and I said to myself, "W T ?"

I think I would be asking for a spec sheet on the fiber, if I were in your shoes..

I'm no fiber expert but it sounds like you may be getting BS'd?

I'd ask for a spec sheet as Brian123 said. Failing that, alert management that the IT department want you to spend however many thousands it'll cost to pull a new cable rather than playing nicely.

As far as I know it's either multimode or single mode. SM gets used for long distance. Both are off the shelf items. I have never come across any other type. Do you have access to the converters at either end? Get a make / model off one of those...

There are some special fibers, such as polarization-maintaining fiber, but that is used when you are trying to detect the polarization of light with optical instrumentation. I don't know what IT would be doing with that stuff.

My BS detector pegs when they say it ain't SM or MM cable. I have to wonder if they built all their own fiber modems if they claim off-the-shelf stuff doesn't work.

I'll update you folks when I learn more. It's a political land mine field so I will proceed with caution.