The SVK SMPP SMS Email Service is delivered with the RadiusCat Billing Licensed Edition. This application runs as a Windows Services and is responsible for sending all Email and SMS messages generated from the RadiusCat application.
The SMS Service uses SMPP allowing the applcation to send thousands of SMS messages at a very high rate and requires interop with an SMS provider (eg: http://www.clickatell.com/).
Please note however that the SMS Service is only Licensed for customers having the 'Enterprise' edition of the RadiusCat Billing.
http://www.svkwiki.com/wiki/Email-SMS-(SMPP)-Service