POP3 SASL SASL AUTH EXTERNAL RFC1734 RFC4422 RFC5034 # # Server-side AUTH EXTERNAL REPLY AUTH + REPLY = +OK Login successful From: me@somewhere To: fake@nowhere body -- yours sincerely # # Client-side pop3 POP3 external authentication without credentials 'pop3://;AUTH=EXTERNAL@%HOSTIP:%POP3PORT/947' # # Verify data after the test has been "shot" CAPA AUTH EXTERNAL = RETR 947 QUIT