Supported by both TIA commercial and data center standards, fiber zone cabling has been around for a while as a viable means for improving manageability, flexibility, scalability and security in a variety of applications—from the casino floor to the data center.
Let’s take another look at the practice of fiber zone cabling and its benefits, applications and considerations.
In the horizontal space, fiber zone cabling logically places connectivity to support a group of devices or work areas. Rather than deploying multiple long home-run copper cables from the closet to each device, active zones involve fewer runs of fiber from the closet to a switch in the zone and then shorter runs of copper that extend from the switch to each device.
Where might we see this deployed? Think of an open office with various work areas or cubicles segregated by department or function, a casino floor with several zones or pods of slot machines, or even a stadium with point-of-sale (POS) machines in one area to support food and beverage vendors.
In these scenarios, the use of shorter runs of copper cabling from the zone makes it easier to install new devices or make changes. It also makes it easier to isolate changes to one zone at a time rather than disrupting the entire space by dealing with long home-run cables for each device. And with the higher bandwidth of fiber, fewer smaller-size fiber cables are needed in pathways.
Another benefit to fiber zone cabling is distance. Also referred to as a collapsed backbone, fiber can extend connectivity up to 300 meters rather than being limited by the 90-meter horizontal copper limitation. This is ideal for remote areas or historical construction that can’t accommodate a closet. Another consideration is the EMI/RFI and security benefits of fiber—if the cabling to a group of devices needs to traverse through high-security or high-interference areas, copper might not be the best option.
Passive zone cabling through the use of zone distribution areas (ZDAs) in the data center also improves flexibility, manageability, scalability and security. Located at the end of row (EoR), middle or row (MoR), or even under the floor or above the cabinets for space savings, a ZDA provides an ideal connection point for groups of server cabinets.
Longer fiber cables can be pre-installed from the core to the ZDA, and new equipment added by simply running shorter cables from the ZDA, rather than all the way from the core. Security is improved because there is no need to access critical core switch cabinets during changes. It also improves scalability by supporting a secure row-based “grow as you go” business model, which is ideal for colocation centers.
In the past, some deemed fiber zone cabling to be too expensive. But with the reduced cost of fiber switch ports and easier installation through innovative field termination and plug-and-play options, that is no longer a major consideration.
However, what is a consideration today for passive zone cabling is insertion loss. Higher speeds like 40- and 100-gigabit Ethernet (GbE) have more stringent loss requirements that can limit the number of connection points within a channel. For example, the use of a ZDA in the data center results in a 3-point architecture, or a 5-point architecture if cross connects are deployed. Thankfully, Belden has achieved the industry’s lowest insertion loss value of just 0.2 dB on OM4 MPO-12 connectors to support both 3- and 5-point ZDA data center architectures.
For more on deploying ZDAs in the data center, read my latest white paper. The use of a ZDA in the data center also has some polarity considerations when using MPO trunks from the core or main cross connect to the ZDA.
Whether the zone is active or passive, in the horizontal or in the data center, located in a cabinet or an enclosure, or placed in the ceiling or under the floor, Belden has the solution to help you get into the zone. Our new low-profile FiberExpress Multi-Box (M-Box) with support for both field termination and pre-terminated fiber supports zone cabling in a variety of environments.
Dwayne Crawford has more than 20 years of experience in the datacomm industry. He has served on several international standards committees to advance high-performance/low-latency protocols (such as IEEE-1394, GigE Vision and CameraLink) used in real-time image processing and utilizing high-performance computing platforms.