Lumentum and Finisar took part in what they claim is the industry's first interoperability demonstration of 100G SWDM4 optical transceivers at ECOC 2016 in Dusseldorf, Germany, this week.
A live data link ran between the Lumentum and Finisar booths with SWDM4 optical transceivers from the two manufacturers exchanging data via a traditional duplex multimode optical fibre. The QSFP28 modules are plugged into test systems provided by Anritsu and Viavi, recording error-free transmission, thus demonstrating the transceivers' ability to communicate with each other.
Shortwave wavelength division multiplexing (SWDM) is a novel technology in short-reach data communications, using multiple data streams from lasers emitting different wavelengths in the 850nm band that are optically multiplexed into a single fibre (see Taking multimode fibre to new wavelengths).
This provides a direct, low-cost upgrade path to 100G for data centre customers who have an installed base of duplex multimode fibre running at 10G today. Before SWDM, data centre operators would have needed to switch to other types of cabling if they wanted to go faster.
“SWDM is expected to play an important part in the migration from a 10G-centric data centre to an architecture based on 40, 100, or 200G,” said James Wynia, director of product management at Dell EMC Networking. "We are pleased to see multiple vendors embrace a common interface because of the security of supply it provides to end customers."
The SWDM Alliance was created in 2015 with the express purpose of promoting this technology in response to a need in the industry. With SWDM4, an optical transceiver with a standard QSFP28/CAUI-4 electrical interface can be plugged into an Ethernet switch or network interface card and drive 100Gb/s over legacy duplex multimode fibre.
The modules from Lumentum and Finisar comply with a common set of transceiver optical specifications in order to provide interoperability of their respective transceivers. This benefits customers by presenting two well-known optical module suppliers with this key technology for the most economical 100Gbps upgrade path.
"This demonstration marks an important step in the development of a low-cost 100G solution for a great many customers who have made the investment over the years in a duplex multimode fibre infrastructure for their data centres," said Kevin Redner, product line manager at Lumentum. "We knew the technology existed to use SWDM for 100G short reach applications and today we're pleased to show that customers can move confidently forward knowing that they have multiple sources for this product."
