Identity confirmation
The Identify confirmation feature, which allows further mechanisms to extend the standard use of e-mail confirmation, is as per the upcoming section.
Enable SMS-based identity confirmation
The Enable SMS-based identity confirmation option enables users to receive a One-Time PIN, which they receive via SMS. Once enabled, administrators or users must verify their mobile phone number before taking advantage of this feature.
Note
This option is enabled by default and can only be disabled by sending a request to salesforce.com support.