In a recent post to The Leviton Blog, the company’s senior director of global product management, fiber and data center, Gary Bernstein, cites a poll the company conducted among data center network professionals to make the case that OM5 multimode fiber has been marginalized.
Conducted earlier in 2018, the poll asked, “What fiber type would you be installing today to plan for future growth?” Response options were OM3, OM4, OM5 and OS2. 45 percent of respondents chose OS2, followed by 39 percent choosing OM4. 13 percent chose OM3 and 2 percent chose OM5.
OM5 multimode fiber supports short-wave division multiplexing, and has proponents in the industry.
Bernstein wrote, “When it comes to network infrastructure, users are reluctant to replace their entire cable backbone. And even with a greenfield installation, they are unlikely to install something different from their existing facilities unless the added capabilities (bandwidth and reach) are extraordinary. Customer and market perception is crystallizing on OM4 for multimode, and when a jump in fiber type is necessary and OM4 will no longer suffice, singlemode is by far the recognized next step.”
The blog post summarizes a “state-of-the-market” of sorts with transceivers, pointing out there are 13 different 100-Gbit transceiver options available today. The post further explains, “Cisco’s recently launched 40/100G BiDi transceiver creates a clean line and transition path for OM4 in 40- and 100-Gbit/sec ports. This new dual-rate transceiver—QSFP-40/100-SRBD—uses a duplex LC interface. Cisco does not really want their customers to install new cabling; they want them to be able to use their existing OM3 or OM4 cabling and upgrade with new transceivers or new switches. And when data center managers plan for speeds and distances beyond 40 or 100 Gbits/sec, they will move to singlemode fiber.
“Transceiver manufacturers are taking a stand and promoting the benefits of reusing existing cabling backbone to speed network upgrades to avoid network disruptions and unnecessary additional costs. There is nowhere in this path for another multimode fiber like OM5.”