Question

I want to authenticate myself using my Gmail ID and password on a Gmail SMTP server. I am using the GSASL library. I have a set of mechanisms that my client supports: Anonymous, External, Login, Plain, SecureID, Digest-MD5 and CRAM-MD5. Does somebody know which mechanism Gmail uses for user authentication?

Answer 1

To quote Google’s documentation for authenticating to GMail’s SMTP:

Outgoing Mail (SMTP) Server – requires TLS: smtp.gmail.com (use authentication)
Use Authentication: Yes
Use STARTTLS: Yes (some clients call this SSL)
Port: 465 or 587

the authentication in this case is “Plain”.