[Unklejoe]

Not surprised to see you on here. I was the guy who got into the discussion about the merits of single mode vs multi mode with a few of your friends on Facebook a while ago. I was in the multi mode camp mainly due to cost reasons whereas they were in the single mode camp for future proofing reasons.

That said, the cost gap between MM and SM optics today is much smaller especially for 10G (and for the fiber itself it seems to have even reversed), so single mode definitely makes more sense. For some reason, MM fiber is still widely deployed in certain niche use-cases though. Not quite sure why.

For example, I know that it's used on modern military jets for their 10GBASE-SR networks. I wonder if it has something to do with being able to repair terminations in the field? I know MM is pretty forgiving that way. Or maybe it's just another case of them adopting whatever was popular at that exact moment.

[sponaugle]

It was surprising the amount of AV related gear that was multimode specific! The cost differential has dropped so much now you can run either at low cost so if you have the space you can run both.

MM is easier to do mechanical splices on, and does seem to be overall less sensitive to damage. If your need is 10G and less than 300m it works well.

As an aside I ran a USB over fiber repeater that was multimode specific by accident I used a single mode fiber (same LC connector), and it worked perfectly.