To get to this page, to to Services → Password Server → General

The Enable Service box lets you enable or disable the service. This service is usually disabled because it is not used by any known current email clients.

The Bindings section is described in the Service Bindings topic.

Bandwidth Throttling allows you to set limits on how fast data will be transferred through this SMTP service. This allows you to prevent it taking up all your available bandwidth. See the Bandwidth Throttling topic for more information.