Feature: Optoelectronics
communication quality, and describes testing approaches that improve the efficiency of quality assurance.
The accelerating adoption of open optical networks Open optical networks are providing greater flexibility in network design by allowing operators to independently select routers, coherent optical modules, ROADMs and optical transport equipment. Network upgrades and capacity expansion can be introduced incrementally whilst reducing dependence on a single vendor. As a result, adoption of open optical architecture continues to grow. However, while open optical networks increase flexibility in
equipment selection, they also increase the number of conditions that require verification before deployment. Te validation burden grows as the number of devices and
possible combinations expand. Traditional single-vendor environments typically validate optical modules and transport equipment as an integrated solution. In open optical networks, however, routers, optical modules and ROADMs oſten come from different vendors, creating many more combinations and test conditions that must be verified before use. Widespread adoption of OpenZR+, with support for multiple
data rates including 100G, 200G, 300G and 400G, further expands the scope of validation. Transmission conditions vary with network architecture and operational requirements, and even on the same platform results can differ according to transmission distance and optical path configuration. Engineers must therefore assess a broader range of variables during interoperability and performance testing.
Why interoperability testing matters Networks based on 400ZR and OpenZR+ do not always deliver the expected results, even when all devices comply with the same industry standards. For example, an optical module that operates normally in a laboratory environment could fail to establish a link when connected to an actual transmission path. In other cases,
Figure 2: Network performance measurement
Even when devices comply with the same standards,
different vendor combinations can affect transmission reach and available performance margins
transmission reach could fall short of expectations, or forward error correction (FEC) performance metrics change aſter service activation. Such problems occur more frequently in multi-vendor environments where routers, optical modules, ROADMs and optical transport equipment originate from different suppliers. Variations in implementation and configuration can affect receiver performance and communication margins, which engineers commonly evaluate using metrics such as pre-FEC bit error rate (BER), optical signal-to-noise ratio (OSNR) and FEC performance. Fault isolation also presents a significant challenge. When
communication quality degrades, engineers must determine whether the root cause resides in the optical module, transmission path or ROADM. Link establishment checks and throughput testing alone can’t identify the location of the degradation. Another important consideration involves the difference
between successful communication and a sufficient communication margin. An increase in optical fibre loss or a reduction in OSNR can raise the BER. As long as FEC scheme continues correcting those errors successfully, the network remains operational and no service interruption becomes visible. A circuit may therefore appear healthy during commissioning, yet communication quality may gradually deteriorate aſter deployment.
www.electronicsworld.co.uk September 2026 23
Page 1 |
Page 2 |
Page 3 |
Page 4 |
Page 5 |
Page 6 |
Page 7 |
Page 8 |
Page 9 |
Page 10 |
Page 11 |
Page 12 |
Page 13 |
Page 14 |
Page 15 |
Page 16 |
Page 17 |
Page 18 |
Page 19 |
Page 20 |
Page 21 |
Page 22 |
Page 23 |
Page 24 |
Page 25 |
Page 26 |
Page 27 |
Page 28 |
Page 29 |
Page 30 |
Page 31 |
Page 32 |
Page 33 |
Page 34 |
Page 35 |
Page 36 |
Page 37 |
Page 38 |
Page 39 |
Page 40 |
Page 41 |
Page 42 |
Page 43 |
Page 44
