Load balancing and failover of distributed media resources in a media server

• US 8,140,695 B2
• Filed: 12/12/2005
• Issued: 03/20/2012
• Est. Priority Date: 12/12/2005
• Status: Expired due to Fees

• Current Assignee: International Business Machines Corporation
• Original Assignee: International Business Machines Corporation
• Inventors: Nusbickel, Wendi L.
• Primary Examiner(s): Backer, Firmin
• Assistant Examiner(s): ALGIBHAH, HAMZA N
• Application Number:
  US11/164,932
• Publication Number:
  US 20070136469A1
• Time in Patent Office: 2,290 Days
• Field of Search: 709/230
• US Class Current: 709/230
• 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, the method comprising:

receiving a first request from a client device requesting a first media processing resource, the first request formatted in accordance with a Media Resource Control Protocol (MRCP);

morphing the first request by translating the first request into a first morphed request formatted in accordance with a Hypertext Transfer Protocol (HTTP) by replacing a Real Time Streaming Protocol (RTSP) portion of the first request with HTTP specific code;

identifying a first server partition comprising a plurality of servers, each of which provides the requested first media processing resource;

from the first server partition, selecting a first server that is least loaded; and

forwarding the first morphed request to the first server in accordance with the HTTP.

2. The method of claim 1, further comprising:

receiving a second request from the client formatted with the MRCP requesting the first media processing resource;

morphing the second request by translating the second request into a second morphed request formatted in accordance with the HTTP by replacing a RTSP portion of the second request with HTTP specific code;

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

3. The method of claim 1, further comprising:

receiving a second request from the client formatted in accordance with the MRCP requesting a second media processing resource;

morphing the second request by translating the second request into a second morphed request formatted in accordance with the HTTP by replacing a RTSP portion of the second request with HTTP specific code;

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 HTTP.

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 from a plurality of server partitions providing different media processing resources.

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

6. The method of claim 5, further comprising an intermediary system establishing a client session with the media servlet on behalf of the client device.

7. The method of claim 6, further comprising supporting the client session by passively allowing cookies to bypass load balancing routing.

18. The method of claim 1, wherein replacing the RTSP portion of the first request with the HTTP specific code comprises:

replacing a line of code of the first request comprising the terms “

ANNOUNCE rtsp”

with the HTTP specific code.

19. The method of claim 1, wherein said step of morphing the first request further comprises:

replacing a line of code comprising the term “

SPEAK”

in an MRCP portion of the first request with a line of code comprising the terms “

MRCPMethod;

Speak”

.

20. The method of claim 19, further comprising:

removing from the RTSP portion of the first request a line of code comprising the term “

Content-Type” and

a line of code comprising the term “

Content-Length”

.

8. A computer readable storage device having instructions stored thereon, which when executed by a processor, causes the processor to perform a method comprising:

receiving a first request from a client device requesting a first media processing resource, the first request formatted in accordance with a Media Resource Control Protocol (MRCP);

morphing the first request by translating the first request into a first morphed request formatted in accordance with a Hypertext Transfer Protocol (HTTP) by replacing a Real Time Streaming Protocol (RTSP) portion of the first request with HTTP specific code;

identifying a first server partition comprising a plurality of servers, each of which provides the requested first media processing resource;

from the first server partition, selecting a first server that is least loaded; and

forwarding the first morphed request to the first server in accordance with the HTTP.

9. The computer readable storage medium of claim 8, further comprising:

receiving a second request from the client formatted with the MRCP requesting the first media processing resource;

morphing the second request by translating the second request into a second morphed request formatted in accordance with the HTTP by replacing a RTSP portion of the second request with HTTP specific code;

determining whether the first server is still least loaded;

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

10. The computer readable storage medium of claim 8, further comprising:

receiving a second request from the client formatted in accordance with the MRCP requesting a second media processing resource;

morphing the second request by translating the second request into a second morphed request formatted in accordance with the HTTP by replacing a RTSP portion of the second request with HTTP specific code;

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

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

11. The computer readable storage medium of claim 8, wherein said selecting the first server that is least loaded further 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 from a plurality of server partitions providing different media processing resources.

12. The computer readable storage medium of claim 8, wherein said forwarding the morphed request further comprises:

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

an intermediary system establishing a client session with the media servlet on behalf of the client device, wherein the client session is supported by passively allowing cookies to bypass load balancing routing.

13. A system for load balancing media resources among a plurality of servers, the system comprising:

a processor

a protocol morpher executable by the processor that;

receives a first request from a client device requesting a first media processing resource, the first request formatted in accordance with a Media Resource Control Protocol (MRCP); and

morphs the first request by translating the first-request into a first morphed request formatted in accordance with a Hypertext Transfer Protocol (HTTP) by replacing a Real Time Streaming Protocol (RTSP) portion of the first request with HTTP specific code; and

a load balancer executable by the processor that;

identifies a first server partition comprising a plurality of servers, each of which provides the requested first media processing resource;

from the first server partition, selects a first server that is least loaded; and

forwards the first morphed request to the first server in accordance with the HTTP.

14. The system of claim 13, wherein:

the protocol morpher receives a second request formatted in accordance with the MRCP from the client requesting the first media processing resource, and morphs the second request into a second morphed request formatted in accordance with the HTTP by replacing a RTSP portion of the second request with HTTP specific code; and

the load balancer determines whether the first server is still least loaded and, if the first server is still least loaded, forwards the second morphed request to the first server in accordance with the HTTP, and, if the first server is not still least loaded, 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 HTTP.

15. The system of claim 13 wherein:

the protocol morpher receives a second request formatted in accordance with the MRCP from the client requesting a second media processing resource, and morphs the second request by translating the second request into a second morphed request formatted in accordance with the HTTP by replacing a RTSP portion of the second request with HTTP specific code; 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 HTTP.

16. The system of claim 13, 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 from a plurality of server partitions providing different media processing resources.

17. The system of claim 13, 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, wherein a client session is created between the protocol morpher and the media servlet by the load balancer passively allowing cookies to pass between the media server and the protocol morpher.