SMTP SASL SASL AUTH PLAIN connection reuse RFC4616 RFC4954 # # Server-side AUTH PLAIN REPLY AUTH 334 PLAIN supported REPLY dXNlci5vbmUAdXNlci5vbmUAc2VjcmV0 235 Authenticated REPLY dXNlci50d28AdXNlci50d28Ac2VjcmV0 235 Authenticated # # Client-side smtp SMTP multiple connection authentication mail body smtp://%HOSTIP:%SMTPPORT/%TESTNUMBER001 --mail-rcpt recipient@example.com --mail-from sender@example.com -u user.one:secret -T %LOGDIR/upload%TESTNUMBER -: smtp://%HOSTIP:%SMTPPORT/%TESTNUMBER002 --mail-rcpt recipient@example.com --mail-from sender@example.com -u user.two:secret -T %LOGDIR/upload%TESTNUMBER # # Verify data after the test has been "shot" EHLO %TESTNUMBER001 AUTH PLAIN dXNlci5vbmUAdXNlci5vbmUAc2VjcmV0 MAIL FROM: RCPT TO: DATA QUIT EHLO %TESTNUMBER002 AUTH PLAIN dXNlci50d28AdXNlci50d28Ac2VjcmV0 MAIL FROM: RCPT TO: DATA QUIT mail body .