The C-ECHO procedures are initiated by the invoking DIMSE-service-user issuing a C-ECHO request primitive. On receipt of the C-ECHO request primitive the DIMSE-C protocol machine shall:
construct a Message conveying the C-ECHO-RQ
send the Message using the P-DATA request service (see 8.1)
On receipt of a Message conveying a C-ECHO-RQ the DIMSE-C protocol machine shall issue a C-ECHO indication primitive to the performing DIMSE-service-user.
On receipt of a C-ECHO response primitive, issued by the performing DIMSE-service-user, the DIMSE-C protocol machine shall:
construct a Message conveying the C-ECHO-RSP
send the Message using the P-DATA request service (see 8.1)
On receipt of a Message conveying a C-ECHO-RSP the DIMSE protocol machine shall issue a C-ECHO confirmation primitive to the invoking DIMSE-service-user, thus completing the C-ECHO procedure.