MIL-HDBK-2051 Fiber Optic Shipboard Cable Topology Design GuidanceThis handbook contains suggested design rules for defining a fiber optic cable topology. In addition, this document describes a suggested approach for developing and designing a fiber optic cable topology FOCT for a Naval platform and also identifies the applicable fiber optic component specifications. This handbook is primarily intended for use by the fiber optic cable topology design engineer, but provides useful information to a system design engineer as well.

Pages 1 - 2 - 3 - 4 - 5 - 6 - 7 - 8 - 9 - 10 - 11 - 12 - 13 - 14 - 15 - 16 - 17 - 18 - 19 - 20 - 21 - 22 - 23 - 24 - 25 - 26 - 27 - 28 - 29 - 30

MIL-HDBK-2051(SH)

3.2.13   Redundant fiber .  A redundant fiber is a fiber within the FOCT which is functionally redundant to another fiber.  Switching to the redundant fiber requires manual reconfiguration.

3.2.14   Redundant trunk .  A redundant trunk is a second cable trunk between two interconnection boxes that requires different routing from the primary

trunk.

3.2.15   Service area .  The compartment or group of compartments that accesses the fiber optic cable plant via a shared interconnection box.

3.2.16   Spare fiber (maintenance spare fiber)   .  A fiber that is not allocated for use by any system, but is reserved for use as a maintenance spare in the case of damage to an allocated fiber within a trunk or local cable that penetrates a deck or bulkhead.

3.2.17   System spare fiber .  A fiber that is reserved for use as a maintenance spare for a particular system in the case of damage to an allocated and used system fiber within the cable.

3.2.18   Trunk.  A trunk is a set of trunk cables that run along the same path between two interconnection boxes.

3.2.19   Trunk cable .  A trunk cable is a fiber optic cable that provides a continuous optical path between interconnection boxes.  Typically, trunk

cables are run in the main cableways and have higher fiber counts per cable than local cables.

3.2.20   Unallocated fiber .  An unallocated fiber is a fiber that is not designated for use for any system, but is required as part of the fiber optic cable plant.  Unallocated fibers include spare fibers and growth fibers.

3.2.21   Unused fiber .  An unused fiber is a fiber that is not designated for use by any system and not required as part of the FOCT.  Unused fibers occur within the FOCT when the required systems fibers are less than the number of fiber available within a standard cable size.

5