termination should coincide with a broadcast shift whenever   possible.   The   ship   must   submit   a COMMSHIFT  message. Termination  Types There are six types of full-period terminations, as follows: l l l l l l Single-channel radioteleprinter using either radio path or landline transmission media; Single-channel  low-data-rate  satellite  access using satellite transmission media; CUDIXS   special   satellite   access   for NAVMACS-equipped  ships  using  satellite transmission media; Multichannel radioteleprinter using either radio path or landline transmission media; Multichannel   radioteleprinter   using   SHF satellite transmission media; and Tactical intelligence (TACINTEL) access for TACINTEL-equipped  ships  using  satellite transmission media. Equipment  Tests To  ensure  that  circuit  equipment  is  in  peak operational  condition,  complete  system  back-to-back off-the-air tests must be completed 24 hours prior to termination activations. Check cryptoequipment back- to-back after daily crypto changes and prior to putting circuits into service. An  aggressive  PMS  and  quality  monitoring program is essential. When checking equipment, look for  power  levels,  scorch  or  burn  marks,  proper operation  of  interlocks,  and  cleanliness.  When  cleaning and inspecting antennas, look for cracks, chips, or blistering of insulators. Also check for deterioration, loose connectors, and correct insulator resistance. COMMSPOT Reports COMMSPOT reports will be submitted by all ships,  including  nonterminated  units,  any  time  unusual communication difficulties are encountered. Ships will submit    the    COMMSPOT    to    the    terminating communications   station.   Timely   submission   of COMMSPOT reports is necessary to minimize further deterioration of the situation. Rules  and  general  instructions  for  preparing JINTACCS formatted COMMSPOT reports are found in the Joint Reporting System (General Purpose Re- ports), NWP 1-03, Supp-1 (formerly NWP 10-1-13). 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. T h e    f r e q u e n c i e s    f o r    N C T A M S    a nd 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 1-14