nanog mailing list archives

Re: Cable standards question


From: Jonathan Lassoff <jof () thejof com>
Date: Mon, 14 Nov 2011 07:38:38 -0800

On Mon, Nov 14, 2011 at 7:12 AM, Jon Lewis <jlewis () lewis org> wrote:

On Mon, 14 Nov 2011, Sam (Walter) Gailey wrote:

 My question is this; Is there an appropriate standard to specify for
fiber-optic cabling that if it is followed the fiber will be installed
correctly? Would specifying TIA/EIA 568-C.3, for example, be correct?

I'm envisioning something like;

"The vendor will provide fiber connectivity between (building A) and
(building B). Vendor will be responsible for all building penetrations and
terminations. When installing the fiber-optic cable the vendor will follow
the appropriate TIA/EIA 568 standards for fiber-optic cabling."


At minimum, I think you should probably specify the type and number of
fibers you want.  i.e. Based on the distance and gear you'll be using, do
you need single-mode, or will multi-mode do (as well as the core/cladding
diameter)?  Generally, but not always, fiber uses one strand for transmit
and another for receive, so a typical fiber run is done using duplex fiber.
 Some optics can transmit and receive over one strand using different
wavelengths.  You might even specify how you want the fiber terminated (SC,
LC, cables hanging from the wall, fiber patch panel, etc.).


I'd agree with this. I wouldn't worry about the standard so much as the
practical aspects of a run. Once you have an idea of the approximate
distance of the run, you can figure out which optics you plan on using.
This will determine what physical connectors you'll need and what your
approximate link budget will be.

Based on that information, you can figure out which type to ask for
(9um/125um single-mode, most likely), a range of path loss that you're
comfortable with, and the physical termination you'd like at either end.

Cheers,
jof


Current thread: