ATP-3-09-30 Observed Fires Download
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Chapter 4 4-16 ATP 3-09.30 28 September 2017 Figure 4-6 Naval Surface Fire Support Request (ATP 3-09.32) AUTHENTICATION 4-85. Although improvements in communication security have allowed us to operate without authentication codes, the following procedures may still apply during degraded communication security situations. The two methods of authentication authorized for use are the challenge and reply and the transmission authentication. The operational distinction between the two is that challenge and reply requires two way communications, whereas transmission authentication does not. For instructions on authentication procedures, refer to the communications electronics operating instructions in the appropriate technical manual and unit standard operating procedure. CHALLENGE AND REPLY 4-86. When nonsecure communications are used and excluding unique fire support operations (such as immediate suppression), consider challenge and reply authentication as a normal element of initial requests for indirect fire. The FDC inserts the challenge in the last read back of the fire request. The observer transmits the correct authentication reply to the FDC immediately following the challenge. Authentication replies exceeding 20 seconds are automatically suspect and a basis for re-challenge. Subsequent adjustment of fire or immediate engagement of additional targets by the observer originating the initial fire request normally would not require continued challenge by the FDC.