MPO And OM4 Go The Distance

When low-loss MPO connections are combined with OM4 mulitmode fiber, longer distances can be achieved.

Now, it’s time to switch gears (again I picture my old GTO) from my first blog post and move to the fiber itself. For typical 10G applications, OM3 multimode fiber was sufficient for even the largest data centers, supporting 10 gigabits per second out to 300 meters and similar distances for fibre channel.

The new OM4 specification is embraced by the fibre channel committee to provide longer distance support for higher data rates such as 16Gig, 32Gig, etc, but there is also benefit on the Ethernet side. The new standards for 40Gig and 100Gig Ethernet are set at 100 meters using OM3 fiber. This means that for anything above 100 meters, you’d have to make the jump to singlemode transceivers on both ends of the link, which is an expensive proposition; more than a factor of 4X for every 40Gig link and a whopping factor of 10X for every 100Gig link. With the new OM4 fiber, the distance limit extends out to 125 meters, or even 150 meters if connection loss is limited to 1.0dB.

Better, but perhaps still not long enough? I think not.

Some of this is limited by the loss of the typical MPO connection, which my previous blog post discusses. When you’re trying to mate 12 fibers at once, tolerances become substantially more critical. With truly low-loss MPO connections, coupled with (what I believe is) the best multimode fiber on the planet for these applications, 170 meters is possible today!

When trying to future-proof your infrastructure, I struggle to see a more powerful value proposition than the combination of OM4 and MPO-based architecture – in any media type – or for any application - period. I hear the proverbial gauntlet hitting the floor – CLANG!

BTW – the movie references in the first blog post??? Bill Murray in “What About Bob” and Steve Martin in “The Pink Panther.”