Origination Service Providers that have been tested include:

• thinQ
• ZIRON
• DID Logic
• voiptalk

All of these service providers can provide PSTN dialled numbers which can be forwarded to a SIP URI.

The billing model differs between some of the service providers.

ZIRON, myDivert and voiptalk charge a fixed monthly charge, and no incoming call charge (per minute), and provide a limited number of channels (number of concurrent calls).

DIDLogic charges an incoming-call-charge after the number of allocated monthly free calls is exceeded. The number of channels included varies by country.

thinQ have a smaller fixed charge, charge an incoming call charge, but allow unlimited concurrent calls. Only US geographic and non-geographic services are offered.