Wavelength-division-multiplexing (WDM) is a key enabling technology in today's high speed digital communication infrastructure that supports vast amount of data transportation which in turn is essential for many data centric informational applications such as, for example, many internet based applications. The transportation of vast amount of data are made via optical digital signals over an extensive optical fiber network across the country or global and such optical signals, riding on different wavelengths (or “colors”), are distributed and/or re-distributed among various parts or branches of the optical network via signal exchanges located at various data centers and other facilities. Sometimes, such signal distribution and/or re-distribution may also involve conversion of signals from optical to electric, and then from electric to optical, in terms of its carrying media.
When optical signals are distributed and/or re-distributed within an optical network, it often involves interconnecting optical signals from one signal handling unit, which may be, for example, an optical signal transponder installed in a shelf hosted by a rack (“bay”), to another signal handling unit which may be located in a same room, in a different room of a same floor, or sometimes in a different floor. FIG. 15 is a demonstrative illustration of an interconnected optical system 900 as is known in the art. System 900 is simplistically illustrated to include a first bay 910 and a second bay 920 located, for example, in a same room of a building. Bay 910 may include, from top to bottom, multiple shelfs such as shelf 911, with each of the shelfs having multiple optical signal transponders.
An optical signal coming from an optical signal transponder located in bay 910 may be connected to another optical signal transponder located in bay 920 via a piece of fiber 902, which may have connectors 901 and 903 at its two ends connecting to the signal transponders. Multiple optical signals from bay 910 may need to be connected to multiple destinations in bay 920, and vise versus, using multiple pieces of fibers. Generally the number of fibers needed equals to the number of optical signals being interconnected between the bays, which is demonstratively illustrated in FIG. 15 by a second piece of fiber 904 and the “dots” in between which represents the existence of many more fibers between bay 910 and bay 920.
With the ever increasing data rate, in particular rapid deployment of WDM technology, the number of optical signals of different wavelengths that need to be interconnected between different bays, and sometimes between different shelfs in a same bay, has increased dramatically resulting in the explosive use of fibers in signal interconnection. FIG. 16 is an exemplary picture of a traditional optical system 990 where optical signal interconnect among the bays are provided by an enormous stack of individual pieces of fibers 991 which, like cooked spaghetti, are usually “dumped” at the backside of the various bays.