System and method for resolving network layer anycast addresses to network layer unicast addresses

• US 20020016860A1
• Filed: 04/26/2001
• Published: 02/07/2002
• Est. Priority Date: 04/28/2000
• Status: Active Grant

• Current Assignee: Online Video Networks, Inc.
• Original Assignee: Online Video Networks, Inc.
• Inventors: Smith, Bradley R., Garcia-Luna-Aceves, J. J.
• Granted Patent: US 7,725,596 B2
• Time in Patent Office: Days
• US Class Current: 709/245
• CPC Class Codes: G06F 12/1483 using an access-table, e.g. matrix or list
• CPC Class Codes: G06F 16/9574 of access to content, e.g. by caching
• CPC Class Codes: H04L 12/18 for broadcast or conference , e.g. multicast
• CPC Class Codes: H04L 61/00 Network arrangements, protocols or services for addressing or naming
• CPC Class Codes: H04L 61/45 Network directories; Name-to-address mapping
• CPC Class Codes: H04L 67/1001 for accessing one among a plurality of replicated servers
• CPC Class Codes: H04L 67/10015 Access to distributed or replicated servers, e.g. using brokers
• CPC Class Codes: H04L 67/1008 based on parameters of servers, e.g. available memory or workload monitoring of computer activity G06F11/30
• CPC Class Codes: H04L 67/101 based on network conditions
• CPC Class Codes: H04L 9/40 Network security protocols

Abstract

An information object repository is configured to resolve a network layer anycast address to a network layer unicast address in response to a request for an information object at the network layer anycast address. The information object repository may be further configured to resolve the network layer anycast address by transmitting a request for the network layer unicast address and awaiting a response thereto, and, in some cases, to return a failure message to a source of the request for the information object if the response to the request for the network layer unicast address is not received within a timeout period. Preferably, the request for the network layer unicast address is a single IP packet that includes the network layer anycast address. Similarly, the request for the network layer unicast address is preferably a single IP packet that includes the network layer unicast address. The response to the request for the network layer unicast address may be returned by a host having the network layer unicast address, or another network node configured to do so.

Claims

1. A method, comprising:

receiving a request for an information object at an anycast network address; and

resolving the request to a corresponding unicast address for the information object.

2. The method of claim 1 further comprising returning the unicast address for the information object.

3. The method of claim 1 wherein the request is received at an information object repository selected without regard as to whether the information object is actually stored at the information object repository.

4. The method of claims 3 further comprising instructing the selected information object repository to obtain a copy of the information object.

5. The method of claim 3 the information object repository is selected according to specified performance metrics.

6. The method of claim 5 wherein the performance metrics comprise one or more of:

average delay from the selected information object repository to a source of the request, average processing delay at the selected information object repository, reliability of a path from the selected information object repository, available bandwidth in said path, and loads on the selected information object repository.

7. An information object repository configured to resolve a network layer anycast address to a network layer unicast address in response to a request for an information object at the network layer anycast address.

8. The information object repository of claim 7 being further configured to resolve the network layer anycast address by transmitting a request for the network layer unicast address and awaiting a response thereto.

9. The information object repository of claim 8 being further configured to return a failure message to a source of the request for the information object if the response to the request for the network layer unicast address is not received within a timeout period.

10. A network, comprising:

at lest one client configured to transmit a request for an information object using a network layer anycast address; and

an information object repository configured to receive the request for the information object and to resolve the network layer anycast address into a network layer unicast address.

11. The network of claim 10 wherein the information object repository is further configured to resolve the network layer anycast address by transmitting a request for the network layer unicast address and awaiting a response thereto.

12. The network of claim 11 wherein the information object repository is further configured to return a failure message to the client if the response to the request for the network layer unicast address is not received within a timeout period.

13. The network of claim 12 wherein the request for the network layer unicast address comprises a single IP packet that includes the network layer anycast address.

14. The network of claim 13 wherein the response to the request for the network layer unicast address comprises a single IP packet that includes the network layer unicast address.

15. The network of claim 14 wherein the response to the request for the network layer unicast address is returned by a host having the network layer unicast address.