Components of a Typical Installation

Just like copper-based cabling systems, fiber-optic cabling systems have a few specialized components, including enclosures and connectors.

Fiber-Optic Enclosures

Because laser light is dangerous, the ends of every fiber-optic cable must be encased in some kind of enclosure. The enclosure not only protects humans from laser light but also protects the fiber from damage. Wall plates and patch panels are the two main types of fiber enclosures. 

When most people think about a fiber enclosure, a fiber patch panel comes to mind. It allows connections between different devices to be made and broken at the will of the network administrator. Basically, a bunch of fiber-optic cables will terminate in a patch panel. Then, short fiber-optic patch or interconnect cables are used to make connections between the various cables. Figure 1 shows an example of a fiber-optic patch panel. Note that dust caps are on all the fiber-optic ports; they prevent dust from getting into the connector and interfering with a proper connection.

 
Figure 1: An example of a fiber-optic patch panel

In addition to the standard fiber patch panels, a fiber-optic installation may have one or more fiber distribution panels, which are very similar to patch panels, in that many cables interconnect there. However, in a distribution panel (see Figure 2), the connections are more permanent. Distribution panels usually have a lock and key to prevent end users from making unauthorized changes. Generally speaking, a patch panel is found wherever fiber-optic equipment (i.e., hubs, switches, and routers) is found. Distribution panels are found wherever multifiber cables are split out into individual cables.

 
Figure 2: A sample fiber-optic distribution panel

Fiber-Optic Connectors

Fiber-optic connectors are unique in that they must make both an optical and a mechanical connection. Connectors for copper cables, like the RJ-45 type connector used on UTP, make an electrical connection between the two cables involved. However, the pins inside the connector only need to be touching to make a sufficient electrical connection. Fiber-optic connectors, on the other hand, must have the fiber internally aligned almost perfectly in order to make a connection. The common fiber-optic connectors use various methods to accomplish this