Users have been installing hybrid (MM+SM) cables in the backbone for years. With the premises fiber optic cabling now including two varieties of 50/125 fiber, 62.5/125 and singlemode fibers, managing the cable plant is more difficult. We have already seen instances of users and installers being confused and getting bad test results, as well as having problems with networks operating when connected over the wrong fiber type.

There is a color code standard in process, TIA-598C that addresses this issue, which we could adopt and reference. Here is what it recommends:

Colored outer jackets or print may be used on Premises Distribution Cable, Premises Interconnect Cable or Interconnect Cord, or Premises Breakout Cable to identify the classification and fiber sizes of the fiber.

When colored jackets are used to identify the type of fiber in cable containing only one fiber type, the colors shall be as indicated in Table 3. Other colors may be used providing that the print on the outer jacket identifies fiber classifications in accordance with subclause 4.3.3. Such colors should be as agreed upon between manufacturer and user.

Unless otherwise specified, the outer jacket of premises cable containing more than one fiber type shall use a printed legend to identify the quantities and types of fibers within the cable. Table 3 shows the preferred nomenclature for the various fiber types, for example "12 Fiber 8 x 50/125, 4 x 62.5/125."

When the print on the outer jacket of premises cable is used to identify the types and classifications of the fiber, the nomenclature of Table 3 is preferred for the various fiber types. Distinctive print characters for other fiber types may be considered for addition to Table 3 at some future date.

Fiber Color Codes

Note: The article is from The Fiber Optic Association www.thefoa.org, edited by Elena.