Dial-out with dynamic IP address assignment

• US 6,778,528 B1
• Filed: 05/17/2000
• Issued: 08/17/2004
• Est. Priority Date: 05/17/2000
• Status: Expired due to Term

• Current Assignee: Cisco Technology, Inc. (Cisco Systems, Inc.)
• Original Assignee: Cisco Technology, Inc. (Cisco Systems, Inc.)
• Inventors: Shannon, Michael, Blair, Dana
• Primary Examiner(s): Pham, Chi
• Assistant Examiner(s): LY, ANH VU H
• Application Number:
  US09/574,568
• Time in Patent Office: 1,553 Days
• Field of Search: 370/351-357, 370/366, 370/389, 370/392, 370/393, 370/395.21, 370/395.5, 370/395.54, 370/400, 370/401, 370/465-467, 370/474-476, 709/227-229, 709/230, 709/238
• US Class Current: 370/352
• CPC Class Codes: H04L 12/2856 Access arrangements, e.g. Internet access asynchronous transfer mode networks H04L12/5601; broadband local area networks H04L12/2801; optical access or distribution networks H04Q11/0067; access to open networks H04L12/5691; digital subscriber line end-user equipment and bit-level processing of data on a PSTN-based network H04M11/00; home network gateways H04L12/2834; wireless access networks H04W
• CPC Class Codes: H04L 12/2872 Termination of subscriber connections
• CPC Class Codes: H04L 61/4557 Directories for hybrid networks, e.g. including telephone numbers
• CPC Class Codes: H04L 61/5014 using dynamic host configuration protocol [DHCP] or bootstrap protocol [BOOTP]
• CPC Class Codes: H04M 7/122 where the PSTN/ISDN access is used as an access to networks other than PSTN/ISDN access arrangements to networks other than PSTN/ISDN H04M7/0066; access arrangements to public data networks H04L12/2856

Abstract

Packet network addresses, such as Internet Protocol addresses, may be assigned dynamically to computer systems accessed from the packet network by dial-out calls through a telephone network. A dial-out destination system will have an assigned name, typically a domain name. In response to a request for translation of the name, a network access server capable of reaching the destination obtains or assigns an address on a temporary basis. The network access server initiates the call to the destination system through the telephone network. The system initiating communication to the destination system uses the assigned address in any subsequent packet data communications. When the communication ends, the address is again available for a new assignment. This approach provides a dynamic address assignment technique for use on dial-out access services.

Claims

1. A network access server, comprising:

a packet network interface, for coupling to and communication of data via a packet switched data network;

a telephone network interface in communication with the packet network interface, for connection to and communication of the data through a switched telephone network;

a programmable controller coupled to the network interfaces for controlling data communications through the network interfaces;

a telephone network interface in communication with the packet network interface, for

a memory coupled to the programmable controller for storing program code executable by the programmable controller; and

executable code stored in the memory, wherein execution of the code by the programmable controller causes the network access server to;

receive a name translation query, via the packet network interface, for a name associated with a destination computer system accessible from the network access server via the switched telephone network;

establish a dial-out link from the telephone network interface through the switched telephone network to the destination computer system associated with the name and initiate data communication via the dial-out link with the destination computer system;

temporarily assign a packet network address to the destination computer system from among a pool of addresses available to the network access server; and

send a response to the query via the packet network interface, the response containing the temporarily assigned packet address as a translation of the name.

2. A network access server as in claim 1, wherein execution of the code by the programmable controller further causes the network access server to pass data packets bearing the assigned address through the network interfaces between the packet switched data network and the dial-out link to the destination computer system.

3. A network access server as in claim 1, wherein execution of the code by the programmable controller causes the network access server to communicate packets associated with the destination computer system over the dial-out link using a local packet address of a node within the destination computer system and to translate between the local packet address and the assigned address, to enable communication of the packets associated with the destination computer system via the packet network interface.

4. A network access server as in claim 1, wherein the name comprises a domain name associated with the destination computer system, and the assigned address comprises an Internet Protocol address.

5. A network access server as in claim 4, wherein the network access server receives the name translation query from a domain name server and sends the response to the domain name server.

6. A network access server as in claim 1, wherein the packet network interface comprises an Internet Protocol interface, and the telephone network interface comprises one or more modems.

7. A network access server as in claim 1, wherein execution of the code by the programmable controller further causes the network access server to contact an authentication, authorization and accounting server to check a user record before completing the assignment of the address to the destination system.

8. A domain name translation system comprising:

a programmable computer;

a packet network interface, for coupling to and communication via a packet switched data network to enable communication of messages relating to name translations;

a database of domain name translations;

a memory coupled to a processor of the programmable computer for storing program code executable by the processor; and

executable code stored in the memory, wherein execution of the code by the processor causes the programmable computer to;

receive a translation query containing domain name, from a communication source, via the packet network interface;

attempt to retrieve a translation record corresponding to the received domain name from the database;

recognize from the attempt that the received domain name relates to a destination accessible via a dial-out link through a telephone network;

send a message containing the received domain name, via the packet network interface, to a network access server capable of establishing the dial-out link through the telephone network to the destination;

receive a packet network address, temporarily assigned to the destination, from the network access server via the packet network interface; and

supply a response message via the packet network interface to the communication source, the response message containing the packet network address temporarily assigned to the destination.

9. A system as in claim 8, wherein the execution of the code by the processor further causes the programmable computer to update a translation record corresponding to the received domain name within the database to include the packet network address temporarily assigned to the destination, in response to receipt thereof from the network access server.

10. A system as in claim 8, wherein the execution of the code by the processor further causes the programmable computer to update the translation record corresponding to the received domain name within the database to delete the packet network address temporarily assigned to the destination, in response to receipt of a message indicating that assignment to the destination is no longer valid.

11. A system as in claim 8, wherein the packet network address temporarily assigned to the destination comprises an Internet Protocol address.

12. A software product, comprising:

a machine readable medium for bearing information; and

executable code carried as the information on the machine readable medium, the executable code forming a control program for a network access server coupled between a packet-switched data network and a telephone network, wherein execution of the control program by a processor of the network access server causes the network access server to perform the steps of;

receiving a name translation query from the packet-switched data network, for a name associated with a destination computer system accessible from the network access server via the telephone network;

establishing a dial-out link through the telephone network to the destination computer system associated with the name;

initiating data communication via the dial-out link with the destination computer system;

temporarily assigning a packet network address to the destination computer system from among a pool of addresses available to the network access server; and

sending a response to the query via the packet-switched data network, the response containing the temporarily assigned packet address as a translation of the name.

13. A software product as in claim 12, wherein execution of the control program by a processor of the network access server causes the network access server to perform the further step of passing data packets bearing the assigned address between the packet-switched data network and the dial-out link to the destination computer.

14. A software product as in claim 12, wherein execution of the control program causes the network access server to perform the further step of processing packets for communication to or from the destination system to translate address data in the packets between the assigned address and a local address used by a node within the computer system.

15. A software product, comprising:

a machine readable medium for bearing information; and

executable code carried as the information on the machine readable medium, the executable code forming a control program for a computer system coupled to a packet switched data network, the control program causing the computer system to perform the following steps when a processor of the computer system executes the code;

receiving a translation query containing a domain name via the packet switched data network;

recognizing that the received domain name relates to a destination accessible via a dial-out link through a telephone network;

sending a message containing the received domain name through the packet switched data network to a network access server capable of establishing the dial-out link through the telephone network to the destination;

receiving a packet network address, temporarily assigned to the destination, from the network access server; and

supplying a response message via the packet switched data network to a source of the translation query, the response message containing the packet network address temporarily assigned to the destination.

16. A software product as in claim 15, wherein the execution of the code by the processor causes the computer system to perform the further step of updating a translation record corresponding to the received domain name within the computer system to include the packet network address temporarily assigned to the destination, in response to receipt thereof from the network access server.

17. A software product as in claim 16, wherein the execution of the code by the processor causes the computer system to perform the further step of updating the translation record to delete the packet network address temporarily assigned to the destination, in response to receipt of a message via the packet switched data network indicating that assignment to the destination is no longer valid.

18. A method of establishing a connection of a computer system and a network access server coupled between a packet-switched data network and a telephone network, the method comprising the steps of:

receiving a name translation query from the packet-switched data network, for a name associated with a destination computer system accessible from the network access server via the telephone network;

establishing a dial-out link through the telephone network to the destination computer system associated with the name;

initiating data communication via the dial-out link with the destination computer system;

temporarily assigning a packet network address to the destination computer system from among a pool of addresses available to the network access server; and

sending a response to the query via the packet-switched data network, the response containing the temporarily assigned packet address as a translation of the name.

19. A method as in claim 18, further comprising the step of passing data packets bearing the assigned address between the packet-switched data network and the dial-out link to the destination computer.

20. A method as in claim 18, further comprising the step of processing packets for communication to or from the destination system to translate address data in the packets between the assigned address and a local address used by a node within the computer system.