Packet-switched telephony call server

1. A system for providing telephony service over the Internet, comprising in combination:

a call client downloadable to a user device located on the Internet, the call client communicating both media and first call-control data across the Internet according to a non-native protocol, the media including voice data, wherein the call client includes a port scan module to identify Internet Protocol ports open for communication;

a database for determining whether a user associated with the user device is authorized to communicate via a call with a second user accessible through a Public-Switched Telephone Network (PSTN);

a gateway located at an interface between the Internet and the PSTN, the gateway communicating according to a native protocol;

a Packet-switched Telephony Service Provider (PTSP) both the media and the first call-control data across the Internet with the call client according to the non-native protocol, the PTSP further communicating both the media and second call-control data across the Internet to the gateway according to the native protocol so that the call can be connected to the PSTN; and

a call logger associated with the PTSP and tracking calls.

2. The system of claim 1 , the PTSP including a call director and a plurality of call handlers, the call director receiving the first call-control data in the non-native protocol over the Internet from a plurality of user devices and distributing further call processing to the plurality of call handlers.

3. The system of claim 1 , further comprising:

a plurality of gateways; and

a proxy server associated with the PTSP, the proxy server receiving and distributing calls across the plurality of gateways according to one or more non-proprietary protocols, including the native protocol.

4. The system of claim 1 , the call client transmitting both the media and the first call control data in packets formatted according to the HTTP protocol.

5. The system of claim 1 , wherein the native protocol is selected from H.323, SIP, and MGCP, and wherein messages according to the non-native protocol are in a format selected from UDP, TCP, and HTTP.

6. The system of claim 1 , wherein the non-native protocol includes a set of data messages in a proprietary format, the set of data messages including a telephone number, a user device IP address, a port number, and a user identification token.

7. The system of claim 1 , wherein the call client receives an “unauthorized” message if by accessing the database, the PTSP determines that the user does not have a sufficient balance to place the call.

8. The system of claim 1 , wherein the call client accepts a selection of an address book entry corresponding to a target indicator.

9. The system of claim 1 , wherein the media format of the native protocol is in the G.711 codec.

10. The system of claim 1 , wherein the PTSP communicates both the media and the first call-control data with the call client over ports selected by the call client's port scan module.

11. A system for providing telephony service over the Internet, comprising in combination:

a user device connected to the Internet and communicating call control information across the Internet according to a non-native protocol, wherein the non-native protocol provides information on call quality;

a gateway located at an interface between the Internet and the Public-Switched Telephone Network (PSTN), the gateway communicating media and call-control information according to a native protocol;

a proxy server receiving call control information according to the native protocol and selecting a gateway to the public switched telephone network;

a database for determining whether a user associated with the user device is authorized to communicate via a call with a second user accessible through the PSTN;

a call server connected to the Internet and communicating first call-control data across the Internet with the user device according to the non-native protocol, and also communicating second call-control data across the Internet with a proxy server according to the native protocol; and

a call logger for tracking calls.

12. The system of claim 11 , wherein the non-native protocol provides information on call quality through pings between the user device and a PTSP associated with the call server.

13. The system of claim 11 , wherein the user device accepts a selection of an address book entry corresponding to a target indicator.

14. The system of claim 11 , wherein the user device communicates media with the gateway according to a native protocol that includes Real Time Protocol over User Datagram Protocol.

15. The system of claim 11 , wherein the user device transmits both the media and the first call-control data in packets formatted according to the HTTP protocol.

16. The system of claim 11 , wherein the native protocol is selected from H.323, SIP, and MGCP, and wherein messages according to the non-native protocol are in a format selected from UDP, TCP, and HTTP.

17. The system of claim 11 , wherein the non-native protocol includes a set of data messages in a proprietary format, the set of data messages including a telephone number, a user device IP address, a port number, and a user identification token.

18. A method for providing telephony service over the Internet, comprising in combination:

receiving a call request from a user device connected to the Internet, wherein the call request includes a telephone number corresponding to a PSTN subscriber, and wherein the call request is in accordance with a non-native protocol;

selecting a call server to process the call request, wherein the selected call server includes a call director to determine whether the user device has used up a maximum number of minutes;

launching a call handler, wherein the call handler receives the call request in the non-native protocol, wherein the call handler converts the call request to a native protocol, and wherein the native protocol is selected from H.323, SIP, and MGCP;

transmitting the call request in the native protocol to a gateway, wherein the gateway implements the native protocol, and forwards the call request to the PSTN subscriber;

communicating media between the user device and the gateway according to User Datagram Protocol; and

logging information about calls so that call durations may be determined.

19. The method of claim 18 , wherein the user device executes a telephony client.

20. The method of claim 18 , wherein the user device receives an “unauthorized” message if the call director determines that the user does not have a sufficient balance to place the call.

21. The method of claim 18 , wherein the user device accepts a selection of an address book entry corresponding to a target indicator.

22. The method of claim 18 , wherein the user device transmits the call request in packets formatted according to the HTTP protocol.

23. The method of claim 18 , wherein messages according to the non-native protocol are in a format selected from UDP, TCP, and HTTP.

24. The method of claim 18 , further comprising selecting the gateway from a plurality of gateways based on at least one gateway selection criterion.

25. The method of claim 18 , wherein the user device is a device selected from the group consisting of a personal computer, a mobile phone, a wireless handheld, and a packet-switched telephone.