(Note: The following has been submitted as a
guest post to CommScope Blogs by Christian Urricariet, senior director of
product marketing for Finisar. Opinions and comments provided in this guest
post, as with all posts to CommScope Blogs, are that of the author and do not
necessarily reflect the views of CommScope.)
and medium-sized enterprise data centers have been widely deploying 10G
Ethernet over duplex multimode fiber for several years. When it comes time to
transition to 40G or even 100G, a few challenges arise:
need to replace duplex patch cords with parallel MPO patch cords, as well as
install additional trunk cables. That can get expensive.
may install single mode fiber to continue to use their familiar duplex
architecture. But it also means using CWDM4 optics, which is also costly.
of these options is particularly attractive. Enterprises would like to upgrade
their data centers without changing the duplex multimode fiber infrastructure
model used in 10G Ethernet.
where short wavelength division multiplexing (SWDM) comes in. The SWDM4
approach, in particular, consists of four vertical cavity surface emitting
lasers (VCSELs) operating at different wavelengths in the 850nm window. They
are multiplexed/demultiplexed inside the quad small form pluggable (QSFP) transceiver
into a pair of multimode fibers (i.e., a standard duplex interface). Each one
of those wavelengths operates at either 10G or 25G, enabling the transmission
of 40G or 100G Ethernet over existing duplex multimode fiber, using LC
CLICK TO TWEET: Want to save money in data center optics? Check out CommScope's blog for a guest post from Finisar.
that are increasing the size of their new data centers are considering
transitioning to single mode fiber cabling and transceivers to support longer
links. This means using relatively expensive LR4/CWDM4 transceivers to only
support a few hundred meters, or using a parallel fiber solution like PSM4,
which requires mastering eight fibers with singlemode MPO connections while
providing very low losses.
However, a cost-effective multimode
solution uses SWDM4 transceivers with the new OM5 wideband multimode fiber. The
supported 40G/100G Ethernet distances can be extended as follows on OM5
An additional benefit of upgrading to OM5
multimode fiber is to future-proof the infrastructure for potential future 200G/400G/800G
multimode interfaces for the data center. Many of them can take advantage of
SWDM technology and are already under consideration by the IEEE.
SWDM and OM5 are a perfect match for new
data center builds, since they offer the best combination of economics and
technology. This technology is not a single-vendor, proprietary solution. A
group of fiber optics components and systems OEMs have formed the SWDM Alliance
and MSA (www.swdm.org). Its goal is to
promote the use of SWDM technology on duplex multimode fiber, as well as to
ensure optical interoperability among the different vendors’ SWDM product
What challenges are you seeing in your