Addressing method and system for using an anycast address

• US 20040107234A1
• Filed: 08/29/2003
• Published: 06/03/2004
• Est. Priority Date: 03/02/2001
• Status: Abandoned Application

• Current Assignee: Spyder Navigations LLC (Intellectual Ventures LLC)
• Original Assignee: Spyder Navigations LLC (Intellectual Ventures LLC)
• Inventors: Rajahalme, Jarno
• Application Number:
  US10/469,414
• Publication Number:
  US 20040107234A1
• Time in Patent Office: Days
• US Class Current: 709/200
• CPC Class Codes: H04L 12/18 for broadcast or conference , e.g. multicast
• CPC Class Codes: H04L 2101/659 Internet protocol version 6 [IPv6] addresses
• CPC Class Codes: H04L 63/0869 for achieving mutual authentication cryptographic mechanisms or cryptographic arrangements for mutual authentication H04L9/3273
• CPC Class Codes: H04L 67/1001 for accessing one among a plurality of replicated servers
• 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 67/1027 Persistence of sessions during load balancing
• CPC Class Codes: H04L 67/1034 Reaction to server failures by a load balancer
• CPC Class Codes: H04L 67/1036 Load balancing of requests to servers for services different from user content provisioning, e.g. load balancing across domain name servers
• CPC Class Codes: H04W 12/069 using certificates or pre-shared keys
• CPC Class Codes: H04W 8/12 between location registers or mobility servers
• CPC Class Codes: H04W 80/04 Network layer protocols, e.g. mobile IP [Internet Protocol]

Abstract

The present invention relates to an addressing method and system for using an anycast address, wherein a data source or server (21 to 23) can be registered in a network device to become a possible receiver for anycast traffic for a specific anycast address. This is achieved by providing a mapping and binding update function of the anycast address to the server'"'"'s real address. The anycast server can provide authentication data to the client providing a proof that the server indeed has been authorized to respond to the used anycast address. Thereby, an anycast address can be used as a source address and an authorization of anycast servers can be provided.

Claims

1. A method for addressing a data source (21 to 23) in a data network by using an anycast address assigned to more than one interface, said method comprising the steps of:

a) designating said data source (21 to 23) in said data network as a possible receiver for data traffic for said anycast address;

b) mapping said anycast address to a real address of said data source (21 to 23); and

c) providing a binding update function for maintaining a mapping between said anycast address and said real address of said data source (21 to 23) between said data source (21 to 23) and either a client (11, 12), or a network node (6) with an anycast agent functionality, or both.

2. A method according to claim 1, wherein said mapping step and/or said binding update function are implemented by using Mobile IPv6 protocol features.

3. A method according to claim 2, wherein said Mobile IP protocol features comprise a home address destination option, a binding update destination option, a binding acknowledgement destination option, and a Mobile IPv6 routing header.

4. A method according to claim 2 or 3, wherein said binding update function includes a method for address mapping authorization.

5. A method according to any one of the preceding claims, wherein a mobility management function of the Mobile IP is used to hand over clients from one data source to another or from a network interface or link to another.

6. A method according to any one of the preceding claims, wherein said data source (21 to 23) binds with said network node (6) to notify its availability.

7. A method according to claim 6, wherein said binding is performed by the Mobile IP Home Binding procedure.

8. A method according to any one of the preceding claims, wherein multiple bindings for the same anycast address to different data sources (21 to 23) are managed by said network node (6).

9. A method according to any one of the preceding claims, wherein said data source (21 to 23) initiates bindings via multiple different IP addresses.

10. A method according to any one of the preceding claims, wherein a service handover from a failed link to a working one is performed by a new binding update to said network node (6) and/or to the clients (11, 12).

11. A method according to any one of the preceding claims, wherein said anycast address is routed to said network node (6) according to an anycast group defined by said anycast address, and wherein a data source wishing to join said anycast group sends a binding update message to said network node (6).

12. A method according to claim 11, wherein a separate unicast or multicast address is used for said binding update message.

13. A method according to claim 11, wherein the Mobile IP dynamic home agent discovery method is used to determine the address of said network node (6).

14. A method according to any one of the preceding claims, wherein a load or capacity information provided by said binding update function or a network topology information is used for selecting a data source (21 to 23) for a client (11, 12) sending a request.

15. A method according to any one of the preceding claims, wherein a binding update with zero life-time is sent to said network node (6) for each binding initiated by a data source (21 to 23), if said data source (21 to 23) needs to by taken down.

16. A method according to any one of the preceding claims, wherein plural ones of said network node (6) are used to serve said anycast address, and wherein an anycast address delivery is used to reach one of said plural ones of said network node (6) for an anycast addressed service request.

17. A method according to claim 16, wherein said one of said plural ones of said network node (6) synchronizes a received binding information with other ones of said plural ones of said network node (6).

18. A method according to any one of the preceding claims, wherein a caching of a client to server association is flushed for clients which do not send data packets to said data source (21 to 23) via said network node (6).

19. A method according to any one of the preceding claims, wherein said network node (6) monitors data sources (21 to 23) addressed by said anycast address, to provide a fault tolerance and/or fail-over support.

20. A method according to any one of claims 5 to 18, wherein said data source (21 to 23) periodically registers to said network node (6) or said network node (6) sends binding requests to said data source (21 to 23) to provide a short term registration, and wherein said data source is assumed to have failed or taken out of service if it has failed to refresh its registration, which is verified by a binding request.

21. A method according to any one of the preceding claims, wherein said network node (6) assumes that said data source (21 to 23) is down when it does not receive any data packets via a reverse tunnel for response packets from said data source (21 to 23), and verifies this by sending a binding request to said data source (21 to 23).

22. A method according to any one of claims 19 to 21, wherein a service request to an anycast address from a client (11, 12) is directed to a different data source, if said client has been communicating with a failed data source at the same anycast address.

23. A system for addressing a data source (21 to 23) in a data network by using an anycast address assigned to more than one interface, said system comprising:

a) mapping means (11, 12;

6) for mapping said anycast address to the real address of said data source (21 to 23); and

b) binding update means (11, 12;

6) for providing a binding update function for maintaining an address relation between a client (11, 12) which has used said anycast address and said data source (21 to 23).

24. A system according to claim 23, wherein said mapping means (11, 12;

6) and/or said binding update means (11, 12;

6) are arranged to use a Mobile IP signaling.

25. A system according to claim 23 or 24, wherein said binding update means is provided at a network node (6) with an anycast agent functionality.

26. A system according to claim 25, wherein said data source (21 to 23) is arranged to bind with said network node (6) to notify its availability.

27. A system according to claim 26, wherein said data source is arranged to perform said binding by using the Mobile IP Home Binding procedure.

28. A system according to any one of claims 25 to 27, wherein said data source (21 to 23) initiates bindings via multiple different IP addresses.

29. A system according to any one of claims 25 to 28, wherein said system is arranged to route said anycast address to said network node (6) according to an anycast group defined by said anycast address.

30. A system according to any one of claims 25 to 29, wherein plural ones of said network node (6) are provided to serve said anycast address, and wherein said system is arranged to use an anycast address delivery to reach one of said plural ones of said network node (6) for an anycast addressed service request.

31. A system according to claim 30, wherein said one of said plural ones of said network node (6) is arranged to synchronize a received binding information with other ones of said plural ones of said network node (6).

32. A system according to any one of claims 25 to 31, wherein said data source (21 to 23) is arranged to periodically register to said network node (6) or said network node (6) is arranged to send binding requests to said data source (21 to 23), to provide a short term registration.

33. A system according to any one of claims 25 to 32, wherein said network node (76) is arranged to use a load or capacity information provided by said binding update function or a network topology information for selecting a data source (21 to 23) for, a client (11, 12) sending a request.

34. A system according to any one of claims 25 to 33, wherein said network node (6) is arranged to manage multiple bindings for the same anycast address to different data sources (21 to 23).

35. A network node for addressing a data source (21 to 23) in a data network by using an anycast address assigned to more than one interface, said network node (6) comprising binding update means for providing a binding update function for maintaining an address relation between a client (11, 12) which has used said anycast address and said data source (21 to 23).

36. A network node according to claim 35, wherein said binding update means are arranged to use a Mobile IP signaling for providing said binding update function.

37. A network node according to claim 35 or 36, wherein said network node (6) is arranged to monitor data sources (21 to 23) addressed by said anycast address, to provide a fault tolerance and/or fail-over support.

38. A network node according to any one of claims 35 to 37, wherein said network node (6) is arranged to assume that said data source (21 to 23) is down when it does not receive any data packets via a reverse tunnel for response packets from said data source (21 to 23), and to verify this by sending a binding request to said data source (21 to 23).

39. A network node according to claim 37 or 38, wherein said network node (6) is arranged to direct a service request to an anycast address from a client (11, 12) to a different data source, if said client has been communicating with a failed data source at the same anycast address.