Hyperscale cloud providers and enterprise data centers both employ extreme density fiber cables. Singlemode fibers support higher data rates (100/400 Gbps) at distances up to 40 m, while multimode fibers are used for lower data rates (10 Gbps) over short-medium distances up to 300 m. Ribbon and MPO trunk cables are prevalent in each fiber type and this require a different test approach often using multi-fiber switches.
Hyperscale cloud service providers and enterprise data centers are all moving toward a full-fiber infrastructure to cope with higher speed server interfaces and bandwidth consumption requirements. Hyperscale's were among the first to embrace singlemode fiber for their infrastructure and continue to do so – enterprise data centers on the other hand tend to use more multimode fiber for server connections since the cost of multimode optics is still cheaper than singlemode optics.
In either application, the volume of fiber links can be enormous with cumulative lengths often reaching thousands of km – testing, analyzing and keeping track of each fiber link can become a nightmare if a disciplined testing and pragmatic reporting approach is not taken from the beginning.
Testing and Reporting Considerations
Fiber lengths in datacenters are usually quite short and don’t contain multiple splicing events like their long-haul or metro fiber counterparts. Using multi-pulse acquisition to optimize range and resolution and the detection of anomalies dispersed over a medium-long haul fiber is no longer relevant - rather the test emphasis in data centers lies in the ability to characterize short fiber runs using OTDRs with small dead zones and short pulse widths.
Optical return loss (ORL) measurements are also critical since fibers support very high data rates and poor ORL can cause bit errors in the system. Proper fiber inspection to check for contamination per IEC standards on single and multi-fiber connectors should also be performed since this contributes to poor ORL and even service disruption of connector damage. Micro-bending and macro-bending issues also require special attention since fiber management in confined spaces and cable runs can be quite intense and bend insensitive fibers with the right characteristics are not really adopted or deployed yet. In other words, the legacy work practices used by a telecom fiber technician no longer apply in data center fiber-cabling environment.
Ultimately, capturing and saving the sheer volume of test data and delivering on the documentation requirements is the most challenging task. We can assist with batch editing and batch analysis of fiber traces including the uploading of valuable test data to a secure cloud repository. The encrypted test data remains at your full disposal for download and/or online analysis.
Contact us to learn more about our services and how we can possibly support you.