Warp drives and gig transceivers!

What do they have in common? "Scotty, I need more power!" While I’m not named Scotty, I hear this request frequently and often in relation to gig transceivers. I need more distance. I need to go over 900 feet on my multimode fiber. I need to achieve transwarp beaming!

  • Oct 12, 2011
  • cxadmin

What do they have in common? "Scotty, I need more power!" While I’m not named Scotty, I hear this request frequently and often in relation to gig transceivers. I need more distance. I need to go over 900 feet on my multimode fiber. I need to achieve transwarp beaming!

While you decide if Star Trek humor is at all funny, let’s consider SX and LX transceivers. The documented distance limitations on SX is about 900ft on multimode 62.5 micron fiber. On LX it’s at about 6.2 miles over single-mode fiber. Those distances sound like hard and fast rules, don't they? Well guess what, the cake is a lie.

As in everything else with technology, rules are often bent or broken in the name of progress. Often customers are faced with situations where they want to move to higher speeds over their fiber but have multimode fiber everywhere. Why does that matter?

Well consider that at 100mb over multimode you could go 2km. Well now you want to go gig? You are stuck with a limit of 900ft. At 10gig, you are down to roughly 90ft. You could see how that could create issues. Sometimes we can get creative and work with it, and other times we are stuck with looking at running new fiber. Single-mode pricing isn't what it used to be but the costs of pulling all new fiber can certainly add up quickly.

It's important to realize that infrastructure does matter. As our cable group is fond of saying here, "respect layer one." While Cisco has come out with gig transceivers for multimode that will go 2km, and they continue to come out with other creative solutions, it's important to prepare your critical long distance runs with the proper cabling. Engineers like myself stand ready to help you navigate the slippery slope and hopefully, like Mr. Scott, help you save the day just in the nick of time. Scottish accent not required!