IALA

Application acknowledgement

Introduction/Additional information:

This IFM should be used by a ship or base station to acknowledge a binary message.
This IFM should be returned to the interrogating station only.

Registrant:
ITU-R.M.1371-1
Message number:
6
DAC:
1
FI:
1
State:
replaced
Number of slots (max):
1
Permitted as from:
01/01/1998
Not to be used after:
01/04/2010
Details:

 Replaced by DAC 1 FI 5 (warning older AIS stations could still use this one)

 Parameter  Number of bits  Description
 IAI/DAC code 10  See Annex 2, Table 20
 Message sequence number 11  Sequence number in the message being acknowledged
 Spare bits 3  Formula for inserting for spare bits
 Total number of bits   24   

Annex 2, Table 20

 DAC  Function identifier  Resulting application identifier (binary)  Resulting application identifier (hex)  Description
1 0  0000 0000 0100 0000 40  Use of these messages, e.g. for aids-to-navigation, VTS, search and rescue, should be as defined in Annex 5
1 1  0000 0000 0100 0001 41
1 2  0000 0000 0100 0010 42
1 3  0000 0000 0100 0011 43
1  …  0000 0000 01XX XXXX  …
1 63  0000 0000 0111 1111  007F