Fiber Testing in Data Centers – Bringing Theory and Practice Workshop#

Svetoslav Nikolov, Jürgen Rummelsberger (EXFO), Kimberley Rotolo, Markus Eilers

• Why: As data rates increase (400G/800G/1.6T), fiber plant testing and validation become critical. The workshop also introduces hollow-core fiber (HCF) measurement techniques — an emerging technology the PM should be tracking.
• What: Hands-on training in modern DC fiber testing methodologies: insertion loss/return loss measurement, transceiver validation (proactive and reactive), high-speed breakout cable testing, and DCO (coherent) transceiver BERT. Introduces HCF measurement challenges. EXFO test equipment is used (vendor-adjacent but educational in nature).
• How: Covers verification of link stability (Pre-FEC BER monitoring), host-to-module interoperability testing (CMIS), and 400G/800G Ethernet test suites. HCF testing is introduced as a new measurement paradigm for ultra-low-latency applications.
• Where applicable: DC operators deploying 400G+ where fiber plant quality directly impacts link margin. HCF content is forward-looking — signals where the industry is heading for latency-critical DCI. Vendor (EXFO) workshop but the testing principles are standards-based.