Why are we fixated on Multimode fiber for high bandwidth communication?

Wayne E Bouchard web at typo.org
Tue Dec 31 19:17:38 UTC 2013

Basic economics.

MM optics come with looser tolerances and are therefore easier to
produce. The wider core of the fiber and higher dispersion allowances
also mean that the fiber is easier to make. The fiber, though, is the
small end of this equation. The optics are the big one.

For those who are buying two or three optics a year, a $150 price
difference is no big deal. For those who buy two or three hundred
optics every other month, this really makes a difference and those are
the ones driving the MM development.


On Tue, Dec 31, 2013 at 02:08:36PM -0500, Jared Mauch wrote:
> On Dec 31, 2013, at 2:00 PM, eric clark <cabenth at gmail.com> wrote:
> > Anyone know why the industry has their head stuck on MultiMode?
> at 10G the optics costs are about 1/3 that of SMF (SR vs LR).
> We tend to keep things SMF, but within many older datacenters MMF is broadly available and does meet the needs at a lower cost.
> There seems to be a shifting trend as well in UPC vs APC connectors.
> I think much of this problem is clearly articulated here: http://xkcd.com/927/
> Everyones needs are a bit different.
> - Jared

Wayne Bouchard
web at typo.org
Network Dude

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