Domain name resolution in a network having multiple overlapping address domains

• US 6,493,765 B1
• Filed: 03/23/1999
• Issued: 12/10/2002
• Est. Priority Date: 03/23/1999
• Status: Expired due to Term

• Current Assignee: RPX Clearinghouse LLC (RPX Corporation)
• Original Assignee: Nortel Networks Limited (Nortel Networks Corporation)
• Inventors: Koester, Greg, Patel, Manish, Meehan, Thomas, Cunningham, Timothy
• Primary Examiner(s): Chin, Wellington
• Assistant Examiner(s): Ho, Chuong
• Application Number:
  US09/274,944
• Time in Patent Office: 1,358 Days
• Field of Search: 709/245, 709/202, 709/238, 709/249, 709/250, 709/239, 370/390, 370/401, 370/392, 370/397, 370/409, 370/351, 370/400
• US Class Current: 709/245
• CPC Class Codes: H04L 61/10 of different types
• CPC Class Codes: H04L 61/4511 using domain name system [DNS]

Abstract

A technique for domain name resolution in a communication network having multiple overlapping address domains involves translating a destination host domain name into a destination host local address that is ambiguous within the communication network, and then translating the destination host local address into a unique destination host global address. A domain name system proxy uses a domain name system server in the destination address domain to translate the destination host domain name into the destination host local address, and uses a network address translator to translate the destination host local address into the destination host global address.

Claims

1. A method for domain name resolution in a communication network having multiple overlapping address domains, the method comprising the steps of:

resolving a destination host domain name into an overlapping destination host local address; and

translating the overlapping destination host local address into a unique destination host global address.

2. The method of claim 1, wherein the step of resolving the destination host domain name into the overlapping destination host local address comprises the steps of:

transmitting to a domain name system server a domain name resolution request message including the destination host domain name; and

receiving from the domain name system server a domain name resolution response message including the overlapping destination host local address.

3. The method of claim 1, wherein the step of translating the overlapping destination host local address into the unique destination host global address comprises the steps of:

transmitting to a network address translator a translation request message including at least the overlapping destination host local address; and

receiving from the network address translator a translation request message including the unique destination host global address.

4. The method of claim 1, comprising the steps of:

receiving a domain name resolution request message from a device in a source address domain, said domain name resolution request message including a destination host domain name associated with a destination host in a destination address domain;

resolving the destination host domain name into the overlapping destination host local address;

translating the overlapping destination host local address into the unique destination host global address; and

transmitting to the device a domain name resolution response message including the unique destination host global address.

5. The method of claim 4, wherein the device is one of:

a source host in the source address domain; and

a domain name system server in the source address domain.

6. The method of claim 4, wherein the step of resolving the destination host domain name into the overlapping destination host local address comprises the steps of:

transmitting to a domain name system server in the destination address domain a domain name resolution request message including the destination host domain name; and

receiving from the domain name system server in the destination address domain a domain name resolution response message including the overlapping destination host local address.

7. The method of claim 4, wherein the step of translating the overlapping destination host local address into the unique destination host global address comprises the steps of:

transmitting to a network address translator a translation request message including at least the overlapping destination host local address; and

receiving from the network address translator a translation request message including the unique destination host global address.

8. The method of claim 4, wherein the destination host global address is a unique destination host global address for the source address domain.

9. An apparatus for domain name resolution in a communication network having multiple overlapping address domains, the apparatus comprising:

resolving logic operably coupled to resolve a destination host domain name into an overlapping destination host local address; and

translating logic operably coupled to translate the overlapping destination host local address into a unique destination host global address.

10. The apparatus of claim 9, wherein the resolving logic comprises domain name system server, interface logic operably coupled to transmit to a domain name system server a domain name resolution request message including the destination host domain name and to receive from the domain name system server a domain name resolution response message including the overlapping destination host local address.

11. The apparatus of claim 9, wherein the translating logic comprises network address translator interface logic operably coupled to transmit to a network address translator a translation request message including at least the overlapping destination host local address and to receive from the network address translator a translation request message including the unique destination host global address.

12. The apparatus of claim 9, comprising:

receiving logic operably coupled to receive a domain name resolution request message from a device in a source address domain, said domain name resolution request message including a destination host domain name associated with a destination host in a destination address domain;

the resolving logic operably coupled to resolve the destination host domain name into the overlapping destination host local address;

the translating logic operably coupled to translate the overlapping destination host local address into the unique destination host global address; and

transmitting logic operably coupled to transmit to the device a domain name resolution response message including the unique destination host global address.

13. The apparatus of claim 12, wherein the device is one of:

a source host in the source address domain; and

a domain name system server in the source address domain.

14. The apparatus of claim 12, wherein the resolving logic comprises domain name system server interface logic operably coupled to transmit to a domain name system server in the destination address domain a domain name resolution request message including the destination host domain name and to receive from the domain name system server in the destination address domain a domain name resolution response message including the overlapping destination host local address.

15. The apparatus of claim 12, wherein the translating logic comprises network address translator interface logic operably coupled to transmit to a network address translator a translation request message including at least the overlapping destination host local address and to receive from the network address translator a translation request message including the unique destination host global address.

16. The apparatus of claim 12, wherein the destination host global address is a unique destination host global address for the source address domain.

17. In a communication system having a source host in a source address domain, a domain name system proxy, a destination host in a destination address domain, and a domain name system server in the destination address domain, a method for domain name resolution, the method comprising the steps of:

causing a first domain name resolution request message to be sent to the domain name system proxy, the first domain name resolution request message including a domain name associated with the destination host;

receiving said first domain name resolution request message by the domain name system proxy;

transmitting, by the domain name system proxy to the domain name system server in the destination address domain, a second domain name resolution request message including the domain name associated with the destination host;

receiving said second domain name resolution request message by the domain name system server in the destination address domain;

resolving the domain name into a destination host local address by the domain name system server in the destination address domain;

transmitting, by the domain name system server in the destination address domain to the domain name system proxy, a first domain name resolution response message including the destination host local address;

receiving said first domain name resolution response message by the domain name system proxy;

translating the destination host local address into a destination host global address by the domain name system proxy; and

transmitting, by the domain name system proxy, a second domain name resolution response message including the destination host global address.

18. The method of claim 17, wherein the step of causing the first domain name resolution request message to be sent to the domain name system proxy comprises:

transmitting the first domain name resolution request message by the source host to the domain name system proxy.

19. The method of claim 17, wherein the communication system further comprises a domain name system proxy in the source address domain, and wherein the step of causing a domain name resolution request message to be sent to the domain name system proxy comprises:

transmitting, by the source host to the domain name system server in the source address domain, a third domain name resolution request message including the domain name associated with the destination host; and

transmitting, by the domain name system server in the source address domain to the domain name system proxy, the first domain name resolution request message including the domain name associated with the destination host.

20. The method of claim 17, wherein the communication network further includes a network address translator in communication with the domain name system proxy, and wherein the step of translating the destination host local address into a destination host global address by the domain name system proxy comprises the steps of:

transmitting, by the domain name system proxy to the network address translator, a translation request message including at least the destination host local address, a source address domain identifier, and a destination address domain identifier;

receiving the translation request message by the network address translator;

translating the destination host local address into the destination host global address; and

transmitting, by the network address translator to the domain name system proxy, a translation response message including the destination host global address.

21. A communication system comprising:

a source host in a source address domain;

a domain name system proxy;

a network address translator;

a destination host in a destination address domain; and

a domain name system server in the destination address domain, wherein the domain name system proxy resolves a destination host domain name into a unique destination host global address for the source host by first using the domain name system server in the destination address domain to resolve the destination host domain name into an overlapping destination host local address and then using the network address translator to translate the overlapping destination host local address into a unique destination host global address for the source address domain.

22. A program product comprising a computer readable medium having embodied there a computer program for domain name resolution in a communication network having multiple overlapping address domains, the computer program comprising:

resolving logic programmed to resolve a destination host domain name into an overlapping destination host local address; and

translating logic programmed to translate the overlapping destination host local address into a unique destination host global address.

23. The program product of claim 22, wherein the resolving logic comprises domain name system server interface logic programmed to transmit to a domain name system server a domain name resolution request message including the destination host domain name and to receive from the domain name system server a domain name resolution response message including the overlapping destination host local address.

24. The program product of claim 22, wherein the translating logic comprises network address translator interface logic programmed to transmit to a network address translator a translation request message including at least the overlapping destination host local address and to receive from the network address translator a translation request message including the unique destination host global address.

25. The program product of claim 22, comprising:

receiving logic programmed to receive a domain name resolution request message from a device in a source address domain, said domain name resolution request message including a destination host domain name associated with a destination host in a destination address domain;

the resolving logic programmed to resolve the destination host domain name into the overlapping destination host local address;

the translating logic programmed to translate the overlapping destination host local address into the unique destination host global address; and

transmitting logic programmed to transmit to the device a domain name resolution response message including the unique destination host global address.

26. The program product of claim 25, wherein the device is one of:

a source host in the source address domain; and

a domain name system server in the source address domain.

27. The program product of claim 25, wherein the resolving logic comprises domain name system server interface logic programmed to transmit to a domain name system server in the destination address domain a domain name resolution request message including the destination host domain name and to receive from the domain name system server in the destination address domain a domain name resolution response message including the overlapping destination host local address.

28. The program product of claim 25, wherein the translating logic comprises network address translator interface logic programmed to transmit to a network address translator a translation request message including at least the overlapping destination host local address and to receive from the network address translator a translation request message including the unique destination host global address.

29. The program product of claim 25, wherein the destination host global address is a unique destination host global address for the source address domain.