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.

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MIL-HDBK-2051(SH)

5.3.1.8   Link performance .  A link loss budget should be calculated for each link in the FOCT unless the system designer has already done so.  The calculations should be made as specified in MIL-STD-2052.  If specific FOCT links are required to have a performance beyond that of a standard FOCT link (see MIL-STD-2042-6), these requirements and the links to which they apply should be noted.  Examples of special performance requirements are requirements for the loss to be lower than the values specified in

MIL-STD-2042-6 or for the total link length to be within specified bounds.

5.3.1.9   FOCT security .  In general, the ship is considered a secure area and normal FOCT security should consist of the installation of fiber optic cables and interconnection boxes in any location aboard the ship.  Normal interconnection box security should be provided through the bolting down of

the interconnection box cover.

5.3.1.9.1   Special security requirements  .  Special security requirements for the FOCT should be determined from the system specifications and the ship specification.  Systems with different security requirements may use the same FOCT, depending upon the specific security requirements.  When the FOCT contains fibers with classified information as well as non-classified information, specific security information can be obtained from NAVSEA Code

03K21.

5.3.1.10   Local area network (LAN) survivability   .

5.3.1.10.1   Distributed implementations  .  For FOCT links that are part of a distributed LAN implementation designed with a normal LAN and a functionally redundant alternate LAN, the following design rules are recommended.

(1)        All FOCT trunk links for the normal LAN should be survivably separated from the FOCT trunk links for the alternate LAN.

(2)   Nonadjacent FOCT trunk links for both the normal and alternate LAN

should be survivably separated.

The criteria for the survivable separation of cables can be determined from section 072 of the ship specification.

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