2011/12/14 Jeff Kell <jeff-kell@utc.edu>
On 12/14/2011 3:37 PM, Keegan Holley wrote:
Single mode just has a smaller core size for the smaller "beam" emitted by laser vs. LED. it works although I've never done it outside of a lab (MM is cheaper). As for the distance it theory that should come down to the optics and your transmit power. Hopefully this is just a cable connecting the router to a long line. I've never heard of a 10K MM fiber run since SX optics can't shoot that far. You should be able to get through the 500m or so that MM optics are rated for, but YMMV (errors, light levels, bounces, etc etc)
Cisco gives specs for SFP LX over MM (they aren't that great at gig, and really suck at 10G; if you have 50u OM3/OM4 you can do much better at 10G).
See SFP/fiber/distance table at
http://www.cisco.com/en/US/prod/collateral/modules/ps5455/ps6577/product_dat...
They specify that line conditioning cables were used. I would say if you're going to bother purchasing why not purchase SM?
We have run LX-over-MM (62.5) on short building runs as a band-aid until SM is available, and trying to do all new building MM with 50u OM3/OM4. We do have some dependence on 62.5u MM - used by our aging Simplex alarm system - which does point-to-point looped token ring <*cough*> on the alarm side.
What distances?
I'm trying to get them to confirm 50u will work point-to-point, but at some non-alarm-points there would be a necessary 50-to-62.5 exchange taking place and I'm not certain how to accomplish that (50->62.5 would likely have tolerable loss, but not 62.5->50).
I don't think changing core sizes in the middle would work even with SM optics.