PRIMARY SHIP-SHORE CIRCUITS

Primary ship-shore (PRI S/S) circuits are encrypted FSK/PSK teleprinter nets that permit ships to transmit messages for delivery ashore. This service is available to units that do not maintain a full-period ship-shore termination. Navy tactical UHF satellites or the HF/UHF spectrum may be used to conduct ship-shore circuit operations. Ships may use this circuit for coordinating and establishing a full-period termination with the shore station.

The frequencies for NCTAMS and NAVCOMTELSTAS that guard primary fleet ship-shore circuits are listed in applicable CIBs distributed by the COMMAREA master stations. These frequencies are subject to change by the cognizant FLTCINC or by the NCTAMS.

OVER-THE-AIR TRANSFER (OTAT) AND OVER-THE-AIR REKEY (OTAR)

There are significant vulnerabilities associated with the handling of paper cryptographic material. Sound application of over-the-air transfer/rekey (OTAT/OTAR) procedures and techniques can reduce the amount of paper keying material required and reduce the potential for compromise. These procedures and techniques are contained in the NAG-16B Procedures Manual for Over-the-Air Transfer (OTAT) and Over-the-Air Rekey (OTAR).

OTAT/OTAR also makes the transfer of keying material more responsive to rapidly changing operational requirements. The use of NAG-16B was developed and verified by extensive use during operation Desert Shield/Storm. The specified procedures served as an effective vehicle for transferring keying to satisfy rapidly changing joint and Navy requirements. Expanded definitions, general procedures, and equipments are found in NAG-16B.

DISTRESS COMMUNICATIONS

Special methods of communication have been developed to use in times of distress and to promote safety at sea and in the air. Distress message traffic is best described as all communications relating to the immediate assistance required by a mobile station in

distress. Distress traffic has priority over all other traffic. All U.S. Navy communicators must be familiar with distress signals to properly evaluate their meanings and to take appropriate action when necessary.

If a ship becomes involved in a distress situation, communications personnel should send distress messages on normal operating encrypted circuits. If the need for assistance outweighs security considerations, the ship's commanding officer may authorize the transmission of an unclassified distress message on one of the national or international distress frequencies.

When a ship in distress is traveling in company with other ships, the ship in distress will transmit the distress message to the officer in tactical command (OTC), who will take appropriate action.