Load Balancing and Failover of Distributed Media Resources in a Media Server

• US 20070136469A1
• Filed: 12/12/2005
• Published: 06/14/2007
• Est. Priority Date: 12/12/2005
• Status: Active Grant

• Current Assignee: International Business Machines Corporation
• Original Assignee: International Business Machines Corporation
• Inventors: Nusbickel, Wendi
• Granted Patent: US 8,140,695 B2
• Time in Patent Office: Days
• US Class Current: 709/226
• CPC Class Codes: H04L 67/02 based on web technology, e.g. hypertext transfer protocol [HTTP]
• 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 67/1034 Reaction to server failures by a load balancer
• CPC Class Codes: H04L 69/08 Protocols for interworking; Protocol conversion

Abstract

A method and a system for load balancing media resources among a plurality of servers. A first request can be received from a client requesting a first media processing resource, the request being formatted in accordance with a first protocol. The first request can be morphed into a first morphed request formatted in accordance with a second protocol. A first server that is least loaded can be selected from a first server partition including a plurality of servers, each of which provides the requested first media processing resource. The first morphed request can be forwarded to the first server in accordance with the second protocol.

Claims

1. A method of load balancing media resources among a plurality of servers comprising:

receiving a first request from a client requesting a first media processing resource, the request being formatted in accordance with a first protocol;

morphing the first request into a first morphed request formatted in accordance with a second protocol;

from a first server partition comprising a plurality of servers, each of which provides the requested first media processing resource, selecting a first server that is least loaded; and

forwarding the first morphed request to the first server in accordance with the second protocol.

2. The method of claim 1, further comprising:

receiving a second request from the client requesting the first media processing resource, the second request being formatted in accordance with the first protocol;

morphing the second request into a second morphed request formatted in accordance with the second protocol;

if the first server is still least loaded, forwarding the second morphed request to the first server in accordance with the second protocol; and

if the first server is not still least loaded, from the first server partition selecting a second server that is least loaded, and forwarding the second morphed request to the second server in accordance with the second protocol.

3. The method of claim 1, further comprising:

receiving a second request from the client requesting a second media processing resource, the second request being formatted in accordance with the first protocol;

morphing the second request into a second morphed request formatted in accordance with the second protocol;

from a second server partition comprising a plurality of servers, each of which provides the requested second media processing resource, selecting a second server that is least loaded; and

forwarding the second morphed request to the second server in accordance with the second protocol.

4. The method of claim 1, wherein said step of selecting the first server that is least loaded comprises:

applying resource selection rules to at least one pattern contained in a message component to identify the requested media processing resource, the message component selected from the group consisting of a uniform resource identifier (URI) and a content-type header; and

referencing at least one partition identifier to identify the server partition comprising the servers providing the requested media processing resource.

5. The method of claim 1, wherein said step of selecting the first server that is least loaded comprises:

referencing a routing list containing a list of available servers; and

querying each of the available servers.

7. The method of claim 1, wherein said step of forwarding the morphed request comprises selecting a media servlet on the first server that is associated with the media processing resource.

8. The method of claim 7, further comprising establishing a client session with the media servlet.

9. The method of claim 8, further comprising supporting the client session by passively allowing cookies to bypass load balancing routing.

10. The method of claim 1, further comprising:

defining the first protocol to be a Media Resource Control Protocol (MRCP);

defining the second protocol to be a Hypertext Transfer Protocol (HTTP); and

distributing the first media processing resource across the plurality of servers.

6. The method of claim 6, further comprising:

removing unavailable servers from the routing list.

11. A machine readable storage having stored thereon a computer program having a plurality of code sections comprising:

code for receiving a first request from a client requesting a first media processing resource, the request being formatted in accordance with a first protocol;

code for morphing the first request into a first morphed request formatted in accordance with a second protocol;

code for selecting a first server that is least loaded from a first server partition comprising a plurality of servers, each of which provides the requested first media processing resource; and

code for forwarding the first morphed request to the first server in accordance with the second protocol.

12. The machine readable storage of claim 11, further comprising:

code for receiving a second request from the client requesting the first media processing resource, the second request being formatted in accordance with the first protocol;

code for morphing the second request into a second morphed request formatted in accordance with the second protocol;

code for determining whether the first server is still least loaded and, if so, forwarding the second morphed request to the first server in accordance with the second protocol and, if not, from the first server partition selecting a second server that is least loaded, and forwarding the second morphed request to the second server in accordance with the second protocol.

13. The machine readable storage of claim 11, further comprising:

code for receiving a second request from the client requesting a second media processing resource, the second request being formatted in accordance with the first protocol;

code for morphing the second request into a second morphed request formatted in accordance with the second protocol;

code for selecting a second server that is least loaded from a second server partition comprising a plurality of servers, each of which provides the requested second media processing resource; and

code for forwarding the second morphed request to the second server in accordance with the second protocol.

14. The machine readable storage of claim 11, wherein said code for selecting the first server that is least loaded comprises:

code for applying resource selection rules to at least one pattern contained in a message component to identify the requested media processing resource, the message component selected from the group consisting of a uniform resource identifier (URI) and a content-type header; and

code for referencing at least one partition identifier to identify the server partition comprising the servers providing the requested media processing resource.

15. The machine readable storage of claim 11, wherein said code for forwarding the morphed request comprises:

code for selecting a media servlet on the first server that is associated with the media processing resource; and

code for establishing a client session with the media servlet.

16. A system for load balancing media resources among a plurality of servers comprising:

a protocol morpher that receives a first request from a client requesting a first media processing resource, the request being formatted in accordance with a first protocol, morphs the first request into a first morphed request formatted in accordance with a second protocol; and

a load balancer that selects a first server that is least loaded from a first server partition comprising a plurality of servers, each of which provides the requested first media processing resource, and forwards the first morphed request to the first server in accordance with the second protocol.

17. The system of claim 16, wherein:

the protocol morpher receives a second request from the client requesting the first media processing resource, the second request being formatted in accordance with the first protocol, and morphs the second request into a second morphed request formatted in accordance with the second protocol; and

the load balancer determines whether the first server is still least loaded and, if so, forwards the second morphed request to the first server in accordance with the second protocol, and, if not, from the first server partition selects a second server that is least loaded, and forwards the second morphed request to the second server in accordance with the second protocol.

18. The system of claim 16 wherein:

the protocol morpher receives a second request from the client requesting a second media processing resource, the second request being formatted in accordance with the first protocol, and morphs the second request into a second morphed request formatted in accordance with the second protocol; and

the load balancer selects a second server that is least loaded from a second server partition comprising a plurality of servers, each of which provides the requested second media processing resource, and forwards the second morphed request to the second server in accordance with the second protocol.

19. The system of claim 16, wherein the load balancer applies resource selection rules to at least one pattern contained in a message component to identify the requested media processing resource, the message component selected from the group consisting of a uniform resource identifier (URI) and a content-type header, and references at least one partition identifier to identify the server partition comprising the servers providing the requested media processing resource.

20. The system of claim 16, wherein the load balancer selects a media servlet on the first server that is associated with the media processing resource and establishes a client session with the media servlet.