Connection Stages

March 26, 2020 Contributors

The connection stages are identical for all versions of Momentum. Find below a list of the codes for the stages and their meanings.

Phase Description
0 while not connected
1 while idle
2 during MAIL FROM
3 after MAIL FROM
4 during RCPT TO
5 after RCPT TO
6 during DATA
7 after DATA
8 while sending BODY
9 reading confirmation
10 during EHLO
11 after EHLO
12 reading BANNER
13 during RSET
14 after RSET
15 during STARTTLS
16 after STARTTLS
17 handshaking TLS
18 renegotiating TLS
19 during XCLIENT
20 after XCLIENT
21 out of band bounce
22 in unknown state

Code 21 is the only message disposition notification (MDN). With the exception of 22, which is unknown, all other stages occur during the SMTP transaction. In other words, they are in-band bounces.