ANTONY SAVVAS 400G TESTING
400G and the changing
TEST AND MEASUREMENT LANDSCAPE
N ot so long ago 400G was merely an ambitious target, but now it’s rapidly becoming mainstream. The 400G data rate is designed to satisfy the ever-increasing demand for higher bandwidth. High- speed networks are under intense pressure from consumer markets as data and tra c volumes explode with the proliferation of devices and services. With this in mind, Anabel Alarcon, product specialist at test giant EXFO, says: “To complicate matters are the entry of new intelligent pluggable transceivers. Networks are expanding their footprints and devising ways to achieve high port density, space savings, highest bit rate per fibre pair and lower power consumption at the lowest possible cost.” Alarcon says that to meet these objectives and growing transceiver
demand, a “huge supply” of transceiver types and an influx of new transceiver vendors are coming into the industry. Such mission-critical transceivers, depending on network and data centre size, can support thousands of servers, routers, core switches and other crucial network applications. Failure of just one of these transceivers can result in complete network failure. “Transceivers are failing for a myriad of reasons. Until recently, data centre and network managers and operators have had little recourse to identifying the source of network faults, whether resulting from active optical cables (AOCs), optical fibres, connectors or the transceivers themselves. “But there are e ective solutions now to address these highly complex challenges, including EXFO’s iOptics, which can validate any pluggable transceiver from 10M to 400G quickly and accurately.” Available on EXFO’s Power Blazer and Netblazer V2 products,
With the arrival of higher network speeds of up to 400G, Antony Savvas considers the challenges that poses for major test system developers.
THREE KEY OPTICAL IMPACTS OF 400G:
THE 400 G ECOSYSTEM
● Optical loss budgets are going to tighten and this impacts the requirements of optical connectors They will need to be made to tighter tolerances and they will need to be installed with much more care. Connectivity vendors are updating their manufacturing testing to measure more accurately. On the deployment side, IL testing and connector inspection will only become more important and put pressure on contractors to strictly follow best practice ● Optical loss bu ets tighten and this forces a redesign of transceiver manufacturing automation This is going to drive even greater adoption of low loss optical switches to ensure loop back losses are minimised. In some cases where power loss due
to automation cannot be avoided, O-band optical amplifiers are going to be required. Test engineers may not have experience with amplifiers, putting very high requirements on power and reflection management ● The LR4 and LR8 formats carry 4 and 8 wavelength channels respectively This changes the way optical power is measured. Selective or channelised power measurements will be needed in manufacturing and in the field. Standard power meters will not measure issues with loss of power on individual wavelengths. It would be possible for a broken interface to look like it meets the TX power specification, despite not working. Only an OSA or channelised power meter will find that issue
The key sectors and major protagonists involved in 400G development. Source: Viavi.
32
| ISSUE 11 | Q4 2017
www.opticalconnectionsnews.com
Made with FlippingBook - Online Brochure Maker