The BlackBerry® Attachment Service converts supported attachments into a format that users can view on their BlackBerry devices. By default, the BlackBerry® Enterprise Server includes the BlackBerry Attachment Service.
The BlackBerry Attachment Service might use increased system resources when it processes numerous conversion requests simultaneously. If you want to increase the number of conversion requests that can occur concurrently without impacting message delivery, you can install a BlackBerry Attachment Service on a computer that is separate from the computer that hosts the BlackBerry Enterprise Server.
When you install the BlackBerry Attachment Service on a computer that is separate from the computer that hosts the BlackBerry Enterprise Server, the installation process installs the BlackBerry Attachment Service and BlackBerry Controller. The BlackBerry Controller monitors the BlackBerry Attachment Service and restarts it if it stops responding.