Method and apparatus for interconnecting a circuit-switched telephony network and a packet-switched data network, and applications thereof

• US 6,333,931 B1
• Filed: 12/28/1998
• Issued: 12/25/2001
• Est. Priority Date: 12/28/1998
• Status: Expired due to Term

• Current Assignee: Cisco Technology, Inc. (Cisco Systems, Inc.)
• Original Assignee: Cisco Technology, Inc. (Cisco Systems, Inc.)
• Inventors: Gouda, Khaled A., Adamian, Andrew, LaPier, David C., Oran, David R., Neighbors, Clay H.
• Primary Examiner(s): Nguyen, Chau
• Assistant Examiner(s): KWOH, JASPER C
• Application Number:
  US09/221,912
• Time in Patent Office: 1,093 Days
• Field of Search: 370/352-563, 370/385, 370/466, 370/467, 370/410, 370/522, 379/88.17, 379/202, 379/201-1-2, 379/201.11, 379/201.12, 379/202.01, 379/203.01, 348/14
• US Class Current: 370/385
• CPC Class Codes: H04L 12/6418 Hybrid transport
• CPC Class Codes: H04L 2012/6472 Internet
• CPC Class Codes: H04L 2012/6486 Signalling Protocols
• CPC Class Codes: H04M 3/24 with provision for checking the normal operation
• CPC Class Codes: H04M 7/0024 Services and arrangements where telephone services are combined with data services arrangements which combine a telephonic equipment and a computer H04M7/0012
• CPC Class Codes: H04M 7/06 using auxiliary connections for control or supervision , e.g. where the auxiliary connection is a signalling system number 7 link

Abstract

A method and apparatus are disclosed for interconnecting a circuit-switched telephone network and a packet-switched data network for communication among them. A signaling trunk of a circuit-switched telephone network is coupled to a signaling access server that is also coupled to a signaling, management and control network. One or more voice trunks of the telephone network are coupled to one or more network access servers, which are also coupled to the control network to thereby receive instructions from the signaling access server. The network access servers are also coupled to a packet-switched data network, such as the global packet-switched network known as Internet. The signaling access server can receive call setup messages and other messages in standard telephone network protocol formats and convert them into call setup messages in a special protocol for communications between the signaling access server and the network access servers. The signaling access server can instruct the network access servers to establish a call, containing voiceband information such as modem-based data calls, from the voice trunks to the data network. Accordingly, the public switched telephone network and the Internet may be interconnected and may inter-communicate without modifying the protocols of either one.

Claims

1. A telecommunications apparatus that interconnects a circuit-switched telephone network and a packet-switched data network to enable communication among the networks and that provides dial outsourcing, comprising:

a signaling access server coupled to a signaling trunk of the telephone network to interchange call signaling messages therewith, and coupled through a control network to one or more network access servers each coupled to a voice of the telephone network to communicate voice-band information thereon, and coupled to receive instructions from the signaling access server through the contol network, and coupled to the data network to communicate data thereon; and

a computer-readable medium coupled to the signaling access server and carrying one or more first sequences of software instructions executed by and controlling the signaling access server which, when executed by the signaling access server, cause the signaling access server to perforn dial outsourcing by carrying out the steps of;

receiving provisioning information from the network access servers that associates each of the network access servers with one of a plurality of Internet Service Providers;

receiving a subscription profile of a caller who is originating a call, wherein the subscription profile identifies one of the Intemet Service Providers to which the caller subscribes;

based on the subscription profile, selecting one of the network access servers for carrying the call into the data network; and

establishing the call originating in the telephone network and containing voiceband information and terminating in the data network via the selected one of the network access servers, based on call signaling information received from the signaling trunk by the signaling access server.

2. The apparatus recited in claim 1, wherein the computer-readable medium further comprises a second sequence of instructions which, when executed by the signaling access server, cause the signaling access server to perform call congestion management by carrying out the steps of:

receiving an initial address message associated with a call originating in the telephone network;

receiving resource usage information from the network access servers that indicates processing load associated with the network access servers;

based on the resource usage information, selecting one of the network access servers for carrying the call into the data network; and

establishing the call originating in the telephone network and containing voiceband information and terminating in the data network via the selected one of the network access servers, based on call signaling information received from the signaling trunk by the signaling access server.

3. The apparatus recited in claim 1, wherein the network access servers are coupled to the data network by an Internet Protocol (IP) backbone apparatus, and wherein the network access servers are coupled to the signaling access server and to a management network by the control network, and wherein the control network, the management network, the signaling access server, and the network access servers communicate using IP.

4. The apparatus recited in claim 1, wherein the signaling trunk and the voice trunk originate in a Common Channel Signaling telephone network.

5. The apparatus recited in claim 1, wherein the signaling trunk is a Signaling System 7 (SS7) trunk, and wherein the data network is a global, packet-switched network that operates using Internet Protocol (IP) and Transmission Control Protocol (TCP).

6. The apparatus recited in claim 1, wherein the signaling trunk is coupled to a Signal Transfer Point of the telephone network and wherein each of the network access servers is coupled to receive the voiceband information from a switch of the telephone network.

7. The apparatus recited in claim 1, wherein the signaling trunk is coupled from the signaling access server to a digital cross connect apparatus that is coupled to the telephone network, and wherein each of the network access servers is coupled by an associated voice trunk to the digital cross connect apparatus to receive the voiceband information therefrom.

8. The apparatus recited in claim 1, wherein the computer-readable medium further comprises a third sequence of instructions which, when executed by the signaling access server, cause the signaling access server to perform dial origination by carrying out the steps of:

receiving call origination information from one of the network access servers that is associated with an Internet Service Provider that is oriating a call from the data network to a called party in the telephone network who uses the Internet Service Provider for Internet access;

establishing the call originating in the data network and terminating at the called party through the telephone network;

receiving data messages from the Internet Service Provider and directed to the called party; and

forwarding the data messages to the called party through the telephone network.

9. The apparatus recited in claim 1, wherein the computer-readable medium further comprises a fourth sequence of instructions which, when executed by the signaling access server, cause the signaling access server to perform access control by carrying out the steps of:

creating and storing an access control policy that specifies that the signaling access server shall block calls based upon one or more pre-defined call criteria selected from among time of day, destination, type of service, protocol used, source number, calling number, transfer status;

receiving a call offer message from the telephone network that contains a called party telephone number;

based on the called party telephone number and the access control policy, determining whether a call associated with the call offer message is allowed to enter the data network;

permitting the call associated with the call offer message to enter the data network through one of the network access severs only when the access control policy indicates that the call is allowed to enter the data network.

10. The apparatus recited in claim 1, wherein the software components further comprise a fifth sequence of instructions which, when executed by the signaling access server, cause the signaling access server to perform calling line identification blocking by carrying out the steps of:

receiving a call setup message that includes a calling line identifier information element for a call originating in the data network and directed to a called party in the telephone network;

suppressing the calling line identifier information element from the call as the call passes through the signaling access server; and

directing the call to the called party in the telephone network without the calling line identifier information element.

11. An apparatus as recited in claim 1, wherein the computer-readable medium further comprises a seventh sequence of instructions which, when executed by the signaling access server, cause the signaling access server to perform calling card thresholding by carrying out the steps of:

creating and storing at the signaling access server a pre-defined policy rule that specifies that the signaling access server shall block all calls placed using a calling card if the calling card is used to place more than a specified number of calls within a specified period of time;

receiving call information for a call that is placed using the calling card;

storing a record of the call that includes a counter value that identifies the number of calls that have been placed using the calling card over a pre-determined time period;

determining whether the counter value is greater than the specified number of the policy rule;

blocking the call when the counter value is greater than the specified number of the policy rule.

12. An apparatus as recited in claim 1, wherein the computer-readable medium further comprises a seventh sequence of instructions which, when executed by the signaling access server, cause the signaling access server to perform calling card thresholding by carrying out the steps of:

creating and storing at the signaling access server one or more access control lists of network addresses;

receiving call messages associated with a call originating in the telephone network and directed to a called party in the data network;

determining that the called party has a network address in the data network that is in one of the access control lists;

blocking the call from entering the data network when the called party has a network address in the data network that is in one of the access control lists.

13. An apparatus as recited in claim 1, wherein the computer-readable medium further comprises a seventh sequence of instructions which, when executed by the signaling access server, cause the signaling access server to perform destination point code blocking by carrying out the steps of:

creating and storing at the signaling access server one or more access control lists of destination point codes;

receiving call messages associated with a call originating in the data network and directed to a called party in the telephone network;

determining a destination point code of the called party;

determining that the called party has is associated with a destination point code in the telephone network that is in one of the access control lists;

blocking the call from entering the telephone network when the called party has a destination point code in the telephone network that is in one of the access control lists.

14. The apparatus recited in claim 1, further comprising:

a cross-connect apparatus logically coupled between the telephone network and both the signaling trunk and the voice trunk;

means, coupled between the signaling trunk and the signaling access server, for communicating call routing signals from the cross-connect apparatus through the signaling trunk and to the signaling access server;

wherein the software components are configured to receive call signaling messages from the means for communicating and over the control netwok, and to communicate the call signaling messages back over the control network to the network access servers.

15. An apparatus as recited in claim 1, wherein the computer-readable medium further comprises a sixth sequence of instructions which, when executed by the signaling access server, cause the signaling access server to perform originating point code screening by carrying out the steps of:

receiving one or more telephone network messages associated with a call originating in the telephone network and directed to a called party in the data network that including a translated called number and an originating point code value;

converting the originating point code value into an originally called number; and

forwarding the originally called number to the called party with the call as the call passes through the signaling access server to one of the network access servers.

16. A method of interconnecting a circuit-switched telephone network and a packet-switched data network for communication among them and that provides dial outsourcing, comprising the steps of:

receiving provisioning information from network access servers that associates each of the network access servers with one of a plurality of Internet Service Providers;

receiving a subscription profile of a caller who is originating a first call, wherein the subscription profile identifies one of the Internet Service Providers to which the caller subscribes;

based on the subscription profile, selecting one of the network access servers for carrying the first call into the data network;

establishing the first call originating in the telephone network and containing voiceband information and terminating in the data network via the selected one of the network access servers, based on call signaling information received from a signaling trunk by a signaling access server; and

wherein the method further provides call congestion management by crying out the steps of;

receiving an initial address message associated with a second call orginating in the telephone network;

receiving resource usage information from the network access servers that indicates processing load associated with the network access servers;

based on the resource usage information, selecting one of the network access servers for carrying the second call into the data network; and

establishing the second call originating in the telephone network and containg voiceband information and terminating in the data network via the selected one of the network access servers, based on call signaling information received from the signaling trunk by the signaling access server.

17. A method of interconnecting a circuit-switched telephone network and a packet-switched data network for communication among them and that provides dial outsourcing, comprising the steps of:

receiving provisioning informafion from network access servers that associates each of the network access servers with one of a plurality of Internet Service Providers;

receiving a subscription profile of a caller who is originating a first call, wherein the subscription profile identifies one of the Internet Service Providers to which the caller subscribes;

based on the subscription profile, selecting one of the network access servers for carrying the call into the data network;

establishing the fist call originating in the telephone network and containing voiceband information and terminating in the data network via the selected one of the network access servers, based on call signaling information received from the signaling trunk by the signaling access server; and

wherein the method further provides dial origination by carrying out the steps of;

receiving call origination information from one of the network access servers that is associated with an Internet Service Provider that is originating a second call from the data network to a called party in the telephone network who uses the Internet Service Provider for Internet access;

establishing the second call originating in the data network and terminating at the called party through the telephone network;

receiving data messages from the Internet Service Provider and directed to the called party; and

forwarding the data messages to the called party through the telephone network.

18. A method of interconnecting a circuit-switched telephone network and a packet-switched data network for communication among them and that provides dial outsourcing, comprising the steps of:

receiving provisioning information from network access servers that associates each of the network access servers with one of a plurality of Internet Service Providers;

receiving a subscription profile of a caller who is originating a first call, wherein the subscription profile identifies one of the Internet Service Providers to which the caller subscribes;

based on the subscription profile, selecting one of the network access servers for carrying the first call into the data network;

establishing the first call originating in the telephone network and containing voiceband information and terminating in the data network via the selected one of the network access servers, based on call signaling information received fiom a signaling trunk by a signaling access server;

receiving a call setup message that includes a calling line identifier information element for a second call originating in the data network and directed to a called party in the telephone network;

suppressing the calling line identifier information element from the second call as the second call passes through the singaling access server; and

directing the second call to the called party in the telephone network without the calling line identifier information element.

19. A method of interconnecting a circuit-switched telephone network and a packet-switched data network for communication among them and that provides dial outsourcing, comprising the steps of:

receiving provisioning information fom network access servers that associates each of the network access servers with one of a plurality of Internet Service Providers;

receiving a subscription profile of a caller who is originating a first call, wherein the subscription profile identifies one of the Internet Service Providers to which the caller subscribes;

based on the subscription profile, selecting one of the network access servers fbr carrying the first call into the data network; and

establishing the first call originating in the telephone network and containing voiceband information and terminating in the data network via the selected one of the network access servers, based on call signaling information received from a signaling trunk by a signaling access server;

receiving one or more telephone network messages associated with a second call originating in the telephone network and directed to a called party in the data network that includes a translated called number and an originating point code value;

converting the originating point code value into an originally called number; and

forwarding the originally called number to the called party with the second call as the second call passes through the signaling access server to one of the network access servers.