SRS (SkySwitch Registrar Seasoning) was developed to thwart fraud attempts of a hacker who potentially has the credentials of a SIP endpoint. The application runs once a minute and it identifies any devices where the source IP of the registration has changed.

When a device is identified, the following logic is applied:

1. If the new IP is NOT in US or Canada (as identified by then change Dial Plan of the User to SRS Restricted.

2. If the new IP is in US or Canada, but other behavior triggers a positive result in our fraud alert test, then change Dial Plan of the User to SRS Restricted.

“SRS Restricted” users are only allowed to call within NANP excluding Caribbean for a 12 hour period. If 12 hours pass without further suspicious activity then the User will be returned to the prior Dial Permission.

If you know with certainty that a User is legitimate and that the SIP credentials have not been compromised, Please create a ticket.

If you would like to exclude a specific Device, User or Domain from the SRS Restrictions, please send a request to the Control Tower by email to