POP3 SASL SASL AUTH PLAIN RFC1734 RFC4616 RFC5034 # # Server-side AUTH PLAIN REPLY AUTH + REPLY c2hhcmVkLW1haWxib3gAdXNlcgBzZWNyZXQ= +OK Login successful From: me@somewhere To: fake@nowhere body -- yours sincerely # # Client-side pop3 POP3 plain authentication with alternative authorization identity pop3://%HOSTIP:%POP3PORT/%TESTNUMBER -u user:secret --sasl-authzid shared-mailbox # # Verify data after the test has been "shot" CAPA AUTH PLAIN c2hhcmVkLW1haWxib3gAdXNlcgBzZWNyZXQ= RETR %TESTNUMBER QUIT