Accessing distributed services in a network

• US 20070174461A1
• Filed: 01/25/2006
• Published: 07/26/2007
• Est. Priority Date: 01/25/2006
• Status: Active Grant

• Current Assignee: Corporation for National Research Initiatives
• Original Assignee: Corporation for National Research Initiatives
• Inventors: Reilly, Sean
• Granted Patent: US 8,423,670 B2
• Time in Patent Office: Days
• US Class Current: 709/226
• CPC Class Codes: H04L 61/4511 using domain name system [DNS]
• 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

Abstract

A set of multiple servers in which each server (a) provides a service having a name or other identifier, and for which each server (b) has a network address that differs from the network addresses of the other servers in the set, and (c) is co-located with a resolution mechanism that maps a name or other identifier of the service that is received from a client to a network address that is local to the resolution mechanism. The resolution mechanisms are operated to enable a client to choose one of the servers as being currently operational and/or accessible to provide the service to the client, and to so choose the server without the client needing to first access the chosen server.

Claims

1. A method comprising:

for a set of multiple servers in which each server (a) provides a service having a name or other identifier, (b) has a network address that differs from the network addresses of the other servers in the set, and (c) is co-located with a resolution mechanism that maps a name or other identifier that is received from a client to a network address that is local to the resolution mechanism;

operating the resolution mechanisms to enable a client to choose one of the servers as being currently operational and/or accessible to provide the service to the client, and to so choose the server without the client needing to first access the chosen server.

2. The method of claim 1 in which the choice of the server depends on a protocol used by the resolution mechanism.

3. The method of claim 1 in which the choice of the server depends on one or more performance attributes of one or more of the servers.

4. The method of claim 3 in which the performance attributes may include measured response times or a measure of relative closeness of the resolution mechanism to the client.

5. The method of claim 3 in which the performance attributes of the servers is stored in the client and updated from time to time.

6. The method of claim 4 in which updating of the performance attributes is derived from requests for resolution as they naturally occur.

7. The method of claim 1 in which the server chosen by the client is the one that responds first to a resolution request from the client.

8. The method of claim 1 in which the resolution mechanism has the same address as the server with which it is co-located.

9. The method of claim 1 in which access to the service is obtained by the client if any one server and its co-located resolution mechanism are working and/or accessible.

10. The method of claim 1 in which some of the co-located resolution mechanisms and servers are clustered and may be accessed using a single network address.

11. The method of claim 8 in which access to the service is obtained by the client if at least one resolution mechanism within the cluster and one server within the cluster are working and/or accessible.

12. The method of claim 1 in which the servers comprise proxy servers.

13. The method of claim 11 in which the proxy servers access back-end services.

14. The method of claim 1 in which a name service registry enables manual removal of network addresses of servers without disrupting the resolution mechanism.

15. The method of claim 1 in which the resolution mechanism co-located with a given server checks the status of the server and ceases responding to resolution requests from clients when the server is not available.

16. The method of claim 1 in which the resolution mechanism requires a valid input code from the client.

17. The method of claim 16 in which the valid input code is used to determine how the resolution mechanism should respond.

18. A system comprising

a set of multiple servers in which each server provides a service having a name or other identifier,

each server having a network address that differs from the network addresses of the other servers in the set and is co-located with a resolution mechanism that maps a name or other identifier of the service that is received from a client to a network address that is local to the resolution mechanism, and

the resolution mechanisms enabling a client to choose one of the servers as being currently operational and accessible to provide the service to the client, and to so identify the server without the client needing to first access the chosen server.