POP3 SASL SASL AUTH OAUTH2 RFC1734 RFC5034 RFC6749 # Server-side AUTH XOAUTH2 REPLY AUTH + REPLY %b64[user=user%01auth=Bearer mF_9.B5f-4.1JqM%01%01]b64% +OK Login successful From: me@somewhere To: fake@nowhere body -- yours sincerely # Client-side pop3 POP3 OAuth 2.0 (XOAUTH2) authentication pop3://%HOSTIP:%POP3PORT/%TESTNUMBER -u user --oauth2-bearer mF_9.B5f-4.1JqM # Verify data after the test has been "shot" CAPA AUTH XOAUTH2 %b64[user=user%01auth=Bearer mF_9.B5f-4.1JqM%01%01]b64% RETR %TESTNUMBER QUIT