If your company is like most that are involved with building or utilizing fiber optic systems, chances are you have a few spools of bare optical fiber laying around the lab.  Since it is critical to ensure fiber-based equipment works as intended prior to deployment in the field, it is a recommended and common practice for engineers to simulate networks using spools of bare optical fiber.  Because there have been a variety of different fibers available over the years, engineers can end up with fair amount of spools at their disposal.

As virtualization and cloud applications become more and more prevalent in Data Centers, POPs, Head-ends, and Central Offices, the available rack space needed to house the equipment for these applications is shrinking.  While the space needed to store, process, route, or switch the data becomes more compact, one thing that remains difficult to reduce is the physical layer infrastructure. As traffic enters or exits a facility, most providers want the capability to monitor what is being delivered or sent to/from their site. At the larger sites, this data traffic is riding on fiber, and in many cases, there are a number of fibers coming into or out of a given site. To be able to accurately monitor this traffic, a passive optical tap is used to duplicate the traffic and send it to a monitoring device that can analyze the header information native to the traffic type.  In the past, these optical taps were relatively expensive and bulky. Even today, most vendors cannot provide more than 24 taps in a single 1RU footprint. 

Fiber optic splitters enable a signal on an optical fiber to be distributed among two or more fibers.  Since splitters contain no electronics nor require power, they are an integral component and widely used in most fiber optic networks.  As a basic example, the diagram below shows how light in a single input fiber can split between four individual fibers (1x4):

Chromatic dispersion is a phenomenon that is an important factor in fiber optic communications.  It is the result of the different colors, or wavelengths, in a light beam arriving at their destination at slightly different times.  The result is a spreading, or dispersion, of the on-off light pulses that convey digital information.  Special care must be taken to compensate for this dispersion so that the optical fiber delivers its maximum capacity.

Engineers performing fiber optic network simulation testing with the goal of certifying that their equipment will work as intended once deployed in the field, often require the use of optical fiber spools to complete these procedures.  Since it is crucial these tests produce both correct and reliable results, below are some tips for ensuring the most positive results.

Written by:  Kyle Miller @ JEM Electronics, Inc.

What are Fiber Optic Attenuators?

In many cases, the primary focus of a fiber network simulation platform is on the electro-optical equipment at both ends of the fiber optic link.  Since the purpose of network simulators is to evaluate the DUT (Device Under Test) equipment, it only makes sense that this is where the attention will be. However, it is a crucial mistake to forget about both the stability and consistency of the test fiber because the DUT test results (performance, pass/ fail, etc) totally depend on knowing that the optical fiber characteristics are consistent and very reliable.

When testing fiber optic equipment intended for longer distances during the development/certification stages, it is vital that engineers ensure their products will operate as intended once installed in the field.  In order to do this, there are a few alternative methods that have been used to accomplish this task.  As a leading provider of network simulation platforms containing real optical fiber spools, questions we commonly receive include: