Pull-configured distribution of imagery

• US 20050138228A1
• Filed: 12/22/2003
• Published: 06/23/2005
• Est. Priority Date: 12/22/2003
• Status: Active Grant

• Current Assignee: International Business Machines Corporation
• Original Assignee: International Business Machines Corporation
• Inventors: Solie, Kevin, Johnston, James S., Quinn, William M., Hornback, Raymond Jr., Ortwein, Andrew M., Kressin, Mark S., Levy, Matthew A.
• Granted Patent: US 8,521,830 B2
• Time in Patent Office: Days
• US Class Current: 710/15
• CPC Class Codes: H04L 12/1827 Network arrangements for conference optimisation or adaptation
• CPC Class Codes: H04L 65/1101 Session protocols
• CPC Class Codes: H04L 65/4038 with floor control
• CPC Class Codes: H04L 67/02 based on web technology, e.g. hypertext transfer protocol [HTTP]
• CPC Class Codes: H04L 67/1097 for distributed storage of data in networks, e.g. transport arrangements for network file system [NFS], storage area networks [SAN] or network attached storage [NAS]
• CPC Class Codes: H04L 67/55 Push-based network services
• CPC Class Codes: H04L 67/5682 Policies or rules for updating, deleting or replacing the stored data
• CPC Class Codes: H04L 69/329 in the application layer [OSI layer 7]
• CPC Class Codes: H04L 9/40 Network security protocols
• CPC Class Codes: H04N 21/222 Secondary servers, e.g. proxy server, cable television Head-end provisioning of proxy services in data packet switching networks H04L67/56
• CPC Class Codes: H04N 21/23106 involving caching operations prefetching while addressing of a memory level in which the access to the desired data or data block requires associative addressing means within memory systems or architectures G06F12/0862; caching at an intermediate stage in a data network H04L67/568

Abstract

The present invention is a method, system and apparatus for flexible image sharing. In a system for flexibly distributing imagery in an image sharing session, an image cache can be disposed between an image sharing host and a plurality of image sharing viewers. Additionally, a multipoint communications server can be disposed between the image cache and the image sharing viewers and can be communicatively linked to the image sharing host. Importantly, a pull-based subscription model can be implemented in an image cache server hosting the image cache. In particular, the model can have a configuration for registering respective ones of the image sharing viewers to receive notifications of available updated imagery. In a preferred aspect of the present invention, the image sharing host can be an application sharing host hosting a shared application among the image sharing viewers.

Claims

1. A system for flexibly distributing imagery over a computer communications network comprising an image cache disposed between an image sharing host and a plurality of image sharing viewers.

2. The system of claim 1, further comprising a multipoint communications server disposed between said image cache and said image sharing viewers and communicatively linked to said image sharing host.

3. The system of claim 1, further comprising a pull-based subscription model implemented in an image cache server hosting said image cache, said model having a configuration for registering respective ones of said image sharing viewers to receive notifications of available updated imagery.

4. The system of claim 1, wherein said image sharing host comprises an application sharing host.

5. The system of claim 3, wherein said updated imagery comprises updated imagery associated with a shared application hosted within said image sharing host.

6. A method for flexibly distributing imagery for a shared application in an application sharing session, the method comprising the steps of:

caching an image frame update for a shared application;

notifying registered ones of a plurality of application sharing viewers of said image frame update; and

,

serving said cached image frame update to requesting ones of said application sharing viewers.

7. The method of claim 6, further comprising the steps of:

partitioning said cached image frame update into multiple sub-sections; and

,

caching said multiple sub-sections.

8. The method of claim 7, wherein said serving step comprises the steps of:

comparing an already served image frame in said requesting ones of said application sharing viewers to said cached image frame update; and

,

serving only changed ones of said multiple sub-sections to said requesting ones of said application sharing viewers.

9. The method of claim 6, wherein said serving step comprises the steps of:

detecting a slow one of said application sharing viewers; and

,

serving a newer image frame to said slow one of said application sharing viewers responsive to a request by said slow one of said application sharing viewers for an older image frame.

10. The method of claim 6, further comprising the steps of:

detecting a late joining one of said application sharing viewers; and

,

serving a pre-defined layout of the shared application to said late joining one of said application sharing viewers in order to facilitate a sequential retrieval by said late joining one of said application sharing viewers of already distributed image frames for the shared application.

11. A machine readable storage having stored thereon a computer program for flexibly distributing imagery for a shared application in an application sharing session, the computer program comprising a routine set of instructions which when executed by a machine cause the machine to perform the steps of:

caching an image frame update for a shared application;

notifying registered ones of a plurality of application sharing viewers of said image frame update; and

,

serving said cached image frame update to requesting ones of said application sharing viewers.

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

partitioning said cached image frame update into multiple sub-sections; and

,

caching said multiple sub-sections.

13. The machine readable storage of claim 12, wherein said serving step comprises the steps of:

comparing an already served image frame in said requesting ones of said application sharing viewers to said cached image frame update; and

,

serving only changed ones of said multiple sub-sections to said requesting ones of said application sharing viewers.

14. The machine readable storage of claim 11, wherein said serving step comprises the steps of:

detecting a slow one of said application sharing viewers; and

,

serving a newer image frame to said slow one of said application sharing viewers responsive to a request by said slow one of said application sharing viewers for an older image frame.

15. The machine readable storage of claim 11, further comprising the steps of:

detecting a late joining one of said application sharing viewers; and

,

serving a pre-defined layout of the shared application to said late joining one of said application sharing viewers in order to facilitate a sequential retrieval by said late joining one of said application sharing viewers of already distributed image frames for the shared application.