Echo control information

           8  7  6  5  4  3  2  1
        1  H  G  F  E  D  C  B  A



B A     Outgoing echo control device information indicator
0 0     No information
0 1     Outgoing echo control device not included and not available
1 0     Outgoing echo control device included
1 1     Outgoing echo control device not included but available

D C     Incoming echo control device information indicator
0 0     No information
0 1     Incoming echo control device not included and not available
1 0     Incoming echo control device included
1 1     Incoming echo control device not included but available

F E     Outgoing echo control device request indicator
0 0     No information
0 1     Outgoing echo control device activation request
1 0     Outgoing echo control device deactivation request (Note)
1 1     Spare
        NOTE - This value will not be generated by the Echo Control Logic defined in Recommendation Q.115.

H G     Incoming echo control device request indicator
0 0     No information
0 1     Incoming echo control device activation request
1 0     Incoming echo control device deactivation request (Note)
1 1     Spare
        NOTE - This value will not be generated by the Echo Control Logic defined in Recommendation Q.115.