CommScope Definitions: What is a Fiber Distribution Hub?

This blog post is part of a series called “CommScope Definitions” in which we will explain common terms in communications network infrastructure.

In today’s fiber world, service providers demand more bandwidth for their subscribers. Their engineers require innovations that make it easier and more cost-effective to build critical fiber connections for delivering gigabit access speeds. One way engineers can accomplish this is by deploying a fiber distribution hub. So, what is that?

A fiber distribution hub (FDH) is an outdoor cabinet that provides the connection between fiber optic cables and interchangeable passive optical splitters in the outside plant segment of the network. It makes it easy and fast to service connections and reconfigurations–serving as a testing point in the outside plant network. If a cabinet is equipped with factory pre-connectorized feeder and distribution cable stubs, it greatly simplifies field installation since splicing can occur in the technician-controlled environment. Fiber distribution hubs vary in size and shape depending on the location in the network and the number of customers needing service.

The best available technology in the early years of fiber-to-the-home deployments was limited to large metal cabinets. Placing an outdoor cabinet on the ground in the utility easement met with little objection from either the carrier or the homeowners. Placing cabinets on concrete pads or utility poles was also common practice. The story today is more nuanced. Permitting restrictions, HOAs, vandalism and security are at the forefront of the outdoor cabinet placement discussion.

Today, FDHs are more space and cost conscious. The markets demand higher subscriber counts, a smaller footprint and a solution for permit restrictions on above ground utility equipment. CommScope recognized this need many years ago and designed the first below-grade FDH which is now capable of serving up to 288 subscribers and is also able to mount on a pole/wall/or strand.  When above-ground outdoor cabinets are allowed, CommScope has pedestal mount offerings from 12 to 132 ports, pole/wall mount options from 12 to 864 ports, and pad/vault mount offerings from 12 to 1152 ports.

FDHs come in different shapes and sizes depending on their placement in the network. There are indoor and outdoor FDHs. In the outdoor environment, there are more choices depending on application and number of customers requiring service. Oftentimes, more than one design will meet the carrier’s requirements, so it important to work with a trusted advisor to determine which is best for your specific application.

Key Takeaway: Fiber Distribution Hubs provide a technician-preferred connection between fiber optic cables and passive optical splitters in the outside plant segment of the network. This allows maximized network flexibility, rapid service shifts and a singular testing demarcation point for the technician. These high fiber counts enable excellent OLT utilization and create a centralized architecture, allowing for future network expansion and offsetting future CAPEX. A good FDH provides high-density fiber connectivity to a compact, weatherproof enclosure to meet increasingly restrictive permitting ordinances.

Resources

• CommScope Fiber Distribution Hub Product Catalog
• CommScope Optical Splitter Product Catalog
• CommScope's Broadband for Everyone Program
• Township to Rural Network Comparison Guide

Article was originally published on December 17, 2015 and updated on August 22, 2024