Simulating Multi-Fiber and MPO Cable Links

Posted by Kevin Miller on Tue, Jun 15, 2021 @ 12:06 PM

In today’s advanced fiber optic networks, multi-fiber cabling is utilized both inside data centers and across vast field networks as it provides the most efficient approach for deploying large counts of fibers using as little physical space as possible.  At the most basic level, a multi-fiber cable is typically comprised of a ribbon cable surrounded by a protective outer jacketing.  These ribbon and/or multi-fiber cables are available with number options when it comes to fiber counts (ex: 8, 12, 24, etc)

In a data center between racks, one might have 12 or 24 fiber patch style cables connecting devices.  Across the network between sites, a larger field cable in the ground will include several of these resulting in larger fibers counts like 72, 144, 288, and so on.  While fibers may be individually terminated at the ends of some links, those between the gear inside the data center often utilize MPO style connectors to minimize the number of total connections.

What are MPO and MTP® Connectors?

An MPO connector is short for "Multi-fiber Push On" connector. This type of connector, which includes the popular branded/proprietary MTP® connectors from USConec®, are widely available in the market from leading manufacturers like USConec® and SENKO®.  While a standard fiber connector (ex: SC, LC, FC, E2000) contains just a single fiber, MPO connectors have multiple fibers ranging from 8-fiber (8F) to 12-fiber, (12F), 24-fiber (24F), and larger counts continuing to be developed.  This higher density approach enables the expanded fiber capacity inside of a single cable, while then reducing individual connections.

In a data center, for example, using a single 12F cable between two racks or devices with 2 connection points is simpler to manage and takes up less physical cable (and port space) than using 12 individual single-fiber patch cables with a total of 24 connection points.  In addition, today's high-speed data rates (e.g.100G) for some applications are achieved with optics/devices that transmit 10G across 10 fibers or 25G across 4 fibers in each direction. MPO cables connected to transceivers enable those applications using the reduced cable count. 

ProLabs 100G QSFP-28 Transceiver

Shown:  ProLabs 100G QSFP-28 Transceiver with MPO

In many cases, a data center, central office, network hub, will have a mix of MPO cabling combined with breakout cables/individual cables/patch panels, depending on the application.

Why Simulate Multi-Fiber MPO Links?

There are a few primary applications where these multi-fiber links are simulated in the lab environment:

  • Device certification – by the manufacturer or those deploying the equipment
  • Latency/delay validation – replicating expected network or transmission delays

For transceiver and device manufacturers who are designing or certifying their technology, simulating real-world conditions is a critical part of the quality assurance process. If an engineering team is designing a new 100G transceiver with a 500m distance specification and MPO connectivity, it must be tested over a real 500m MPO fiber link to ensure it is optically functioning as expected over that distance before going into production. Additionally, once a finished product is in production, the QA team may also run a final test over the simulated link to ensure the product passes its final inspection before shipping to the customer.

Secondly, engineers at service providers and data centers tasked with selecting and deploying MPO-connected devices in their network may also wish to replicate their own unique fiber links when validating or certifying the necessary equipment prior to purchase.  The last thing any network engineering team wants to do is spend a large sum of money on equipment and later determine it doesn’t meet all of the needs (this does happen when proper testing procedures are skipped or not implemented!)

Lastly, simulating multi-fiber links can be important for latency-driven applications inside the data center.  Along with testing for optical performance characteristics, simulating the expected time delays between devices, racks, or facilities is becoming more critical each day.  For some applications like financial trading where inches or even millimeters of fiber are of importance for latency calculations, effectively simulating those data center links can be very helpful to optimize timing and system performance. 

Fiber Lab MPO – The Most Efficient Approach

Simulating multi-fiber cable spans terminated with MPO connectors presents a challenge compared to simulating a single fiber span, as it requires the fibers to be jacketed or coated in order to stay joined together and aligned properly.  Due to the increased physical diameter of the jacketed cable, the maximum length of the cable that can be spooled onto a reel is reduced significantly compared to using a “bare” single optical fiber.  In addition to varying diameter sizes, jacketed cable comes in a variety of forms like round, flat ribbon, and others that can change parameters and require adaptations and customizations to be made accordingly.

Fortunately, both an experienced partner and a proven solution set are available for anyone needing to simulate these types of specialized links effectively.  Combining M2 Optics Fiber Lab platforms with advanced multi-fiber spooling capabilities, engineers now have numerous solution options available from which to choose based on the project requirements.

Fiber Lab MPO Network Simulator

Shown:  Portable Fiber Lab 800 (300m OM4 and MTP® connectors)

With a customized approach to packaged optical fibers, M2’s Fiber Lab MPO solutions can be delivered in any Fiber Lab product, rack-mount or portable, and to any lengths within the physical constraints.  Whether 300 meters of 12F OM4 in a portable enclosure are required to simulate a span between racks/devices, or several 2.5km lengths of 12F SMF are preferred in a rack-mount enclosure for simulating multiple links between two data center facilities, a Fiber Lab MPO can be built to the project specifications.

Learn More!

After reading this article, do you have questions about simulating multi-fiber links?  If so, contact the M2 Optics team today to have your questions answered and receive more information about these specialized solutions.  With a shared goal of always helping engineers improve the way you use and manage fiber for testing applications, the M2 team is always available to support  you.

Topics: network simulation