Encrypted Message Acknowledgement

Introduction/Additional information: 

This Message 25 payload is used to acknowledge reception of addressed, encrypted STEDS messages.

    1.  

Usage Notes

  • Acknowledgement linkage back to the original message is based upon source MMSI, source FI, and source Message Linkage ID.
  • If the received FID 17 (Encrypted Text Message), has its “ACK flag” field set to zero, then this acknowledgement shall not be sent. Otherwise, all encrypted, addressed STEDS messages receive an ACK.
  • If the sending PI does not receive an ACK after 4 seconds, the sending PI shall retry transmission. The sending PI shall retry a maximum of three times, waiting 4 seconds each time for an ACK. This indicates a maximum of four transmitted messages: one initial and three retries.
Permitted as from: 
12/05/2016
Registrant: 
USCG
Message number: 
25
DAC: 
366
FI: 
9
Version: 
0
State: 
in force
Number of slots (max): 
1
Last modified: 
20210129T231912