[Dovecot] Difference between LOGIN and PLAIN

[Stephan Bosch]

On 11/3/2011 9:42 PM, Simon Brereton wrote:
> Hi
>
> Could someone explain to me the difference between LOGIN and PLAIN?
> I've been googling for a while, but haven't found anything.

The LOGIN SASL mechanism is an obsolete plain text mechanism. It is 
documented here:

http://tools.ietf.org/html/draft-murchison-sasl-login-00

Some clients still support it, but I would not recommend using it when 
PLAIN or a better SASL mechanism is also available at both ends. The 
PLAIN mechanism is documented here:

http://tools.ietf.org/html/rfc4616

The main technical difference between the two is that the PLAIN 
mechanism transfers both username and password in a single SASL 
interaction, where LOGIN needs two. The PLAIN mechanism also provides 
support for having an authorization id different from the authentication 
id, allowing for master user login for example.

Regards,

Stephan.