Outside Plant or Premise

Which Fiber Optic?

Fiber optic cabling is divided in to two categories Outside Plant (OSP) and Premises Cabling.

Outside Plant (OSP)

Telephone companies, CATV and the Internet all use lots of fiber optics, virtually all of which is singlemode fiber and most of which is outside buildings. It hangs from poles, is buried underground, pulled through conduit or is even submerged underwater. Most of it goes relatively long distances, from a few hundred feet to hundreds of miles.
Outside plant cables often have very high fiber counts, up to 288 fibers or more. Cable designs are optimized for the application: cables in conduit for pulling tension and resisting moisture, buried cables for resisting moisture and rodent damage, aerial for continuous tension and extreme weather and undersea for resisting moisture penetration. Installation requires special equipment like pullers or plows, and even trailers to carry giant spools of cable.
Long distances mean cables are spliced together, since cables are not manufactured in lengths longer than about 45 km (2.-3 miles), and most splices are by fusion splicing. Connectors on factory made pigtails are spliced onto the end of the cable. After installation, every fiber and every splice is tested.
The installer usually has a temperature controlled van or trailer for splicing and/or a bucket truck.
Most outside plant telephone installs are done by the telco themselves, while a small number of specialized installers do CATV, utility and municipal work.

Premises Cabling

By contrast, premises cabling- cabling installed in a building or campus - involves shorter lengths, rarely longer than a few hundred feet, typically with fewer fibers per cable. The fiber is mostly multimode, except for the power user who installs hybrid cable with both multimode and singlemode fibers.
Splicing is practically unknown in premises applications. Cables between buildings can be bought with double jackets, PE for outside plant protection over PVC for building applications requiring flame retardant cable jackets, so cables can be run continuously between buildings. Today's connectors often have lower loss than splices, and patch panels give more flexibility for moves, adds and changes.
Termination is installing connectors directly on the ends of the fibers, primarily using adhesive or sometimes prepolished splice techniques. Testing is done by a source and meter. Unlike the outside plant technician, the premises cable installer (who is often also installing the Cat 5/6 for LANs too!) probably has an investment of less than $2,000 in tools and test equipment.
Cabling installers who do fiber optic work have found out it isn't "rocket science," and their small initial investment in training, tools and test equipment is rapidly paid back

Few installers do both outside plant and premises cabling. The companies that do are usually very large and often have separate divisions doing each with different personnel.