Service framework for computing devices

• US 6,604,140 B1
• Filed: 09/23/1999
• Issued: 08/05/2003
• Est. Priority Date: 03/31/1999
• Status: Expired due to Term

• Current Assignee: Wistron Corporation
• Original Assignee: International Business Machines Corporation
• Inventors: Islam, Nayeem, Gefflaut, Alain Franck, Beck, James Edward
• Primary Examiner(s): Najjar, Saleh
• Application Number:
  US09/404,661
• Time in Patent Office: 1,412 Days
• Field of Search: 709/100, 709/104, 709/201, 709/225, 709/226, 709/229, 709/300, 709/304, 709/310, 709/330, 709/331, 709/332
• US Class Current: 709/226
• CPC Class Codes: G06F 9/5055 considering software capabilities, i.e. software resources associated or available to the machine
• CPC Class Codes: H04L 67/34 involving the movement of software or configuration parameters network booting or remote initial program loading [RIPL] G06F9/4416
• CPC Class Codes: H04L 67/51 Discovery or management thereof, e.g. service location protocol [SLP] or web services

Abstract

A method, apparatus and computer product that enables one or more computing devices to discover and use services over a network, which may be ad-hoc when the computing device is mobile. Service discovery is based on periodic multicasting of exported service descriptions to nearby devices over the (ad-hoc) network. Middleware enables a device to discover, advertise and use services. This enables software clients on the same device to share a service implementation (in the case of a local service) or to share an implementation proxy (in the case of a remote service). Each device being aware of the services (and service locations) that are currently available generally reduces the response time associated with accessing available services. While service descriptors are multicast and discovered, the service software is only downloaded on the device when the service is used. This enables economical resource management that is particularly useful for mobile devices.

Claims

1. A method for a first device to discover at least one service available from a second device, said method comprising:

said first device listening for availability of at least one service from said second device;

said second device advertising availability of said at least one service and providing an enhanced service descriptor for said at least one service, said enhanced descriptor providing information regarding the location of code for implementing said at least one service;

said first device receiving said at least one service descriptor; and

implementing lazy loading for said at least one service, including loading code for said at least one service when said at least one service is referenced by said first device.

2. A method as recited in claim 1, further comprising employing multicast messaging protocol.

3. A method as recited in claim 1, wherein the step of listening includes employing an optional service.

4. A method as recited in claim 1, further comprising employing the Java language.

5. A method as recited in claim 1, wherein said at least one service is code running on the second device.

6. A method as recited in claim 1, further comprising said first device and said second device participating in an ad-hoc network.

7. A method as recited in claim 1, wherein said service descriptor is an enhanced descriptor.

8. A method as recited in claim 1, further comprising running the code for said at least one service.

9. A method as recited in claim 8, further comprising removing said service descriptor of said at least one service upon receiving a removal command.

10. A method as recited in claim 9, wherein said removal command is in response to lapse of a period of validity.

11. A method as recited in claim 1, wherein the step of advertising is performed repetitively.

12. A method as recited in claim 1, wherein the step of advertising includes said second device creating the service descriptor for at least a particular service to be advertised by said second device.

13. A method as recited in claim 1, further comprising said second device creating the service descriptor for at least one discovered service.

14. A method as recited in claim 1, wherein said at least one service is a remote service.

15. A method as recited in claim 1, wherein the step of receiving includes accepting and storing the service descriptor for said at least one service.

16. A method as recited in claim 15, further comprising determining a period of validity for said service descriptor for said at least one service.

17. A method as recited in claim 16, wherein the period of validity is a defined time interval.

18. A method as recited in claim 17, wherein the time interval is 10 seconds.

19. A method as recited in claim 14, wherein said service descriptor includes a physical location of said remote service.

20. A method as recited in claim 19, wherein said physical location comprises at least an IP address.

21. A method as recited in claim 20, further comprising employing Java Remote Method Invocation for implementing said at least one service.

22. A method as recited in claim 1, further comprising employing said second device for advertising said at least one service on behalf of a third device.

23. A method as recited in claim 22, wherein said third device is a printer.

24. A method as recited in claim 23, wherein said second device is a PC connected to said third device.

25. A method as recited in claim 1, further comprising repeating the steps of advertising and receiving for at least one other service included in said at least one service.

26. A method as recited in claim 25, further comprising said first device employing said at least one service and said at least one other service.

27. A method as recited in claim 1, further comprising said first device providing the capability of said second device to another device.

28. A method as recited in claim 1, wherein said at least one service is associated with a plurality of applications on said first device.

29. A method as recited in claim 28, further comprising said first device operating by employing only a single copy of said at least one service.

30. A method as recited in claim 1, further comprising employing a service adapter between said at least one service and at least one application.

31. A method as recited in claim 30, wherein said service adapter enables a utility selected from the group consisting of:

security functions, updating functions, load balancing functions, hot swap functions, language utility, and any combinations of these utilities.

32. A method as recited in claim 1, further comprising filtering said service descriptor.

33. A method as recited in claim 32, wherein said step of filtering includes ignoring at least one particular service descriptor in accordance with a filtering policy.

34. A method as recited in claim 1, further comprising implementing life-cycle management of said at least one service.

35. A method as recited in claim 34, where in said life-cycle management performs a function selected from a group consisting of:

registration, lookup, binding, removal, update, and any combinations of these functions.

36. A method for a first device to discover at least one available service, said method comprising:

employing a service framework defining and providing life-cycle management of at least one service running on at least a single device by;

distributively discovering at least one desired service from said at least one service among devices in an ad-hoc network, said desired service providing an enhanced discriptor, said enhanced descriptor providing information regarding the location of code for implementing said at least one service; and

implementing lazy loading for said at least one service, including loading code for said at least one service when said at least one service is referenced by said first device.

37. A method as recited in claim 36, further comprising dynamically downloading information regarding said desired service.

38. A method as recited in claim 36, wherein at least a particular service included in said at least one service is remote.

39. A method as recited in claim 36, wherein said at least one service has an associated period of validity.

40. A method as recited in claim 36, wherein said at least one service is usable by a plurality of applications on said single device.

41. A method as recited in claim 36, wherein said at least one service includes a service adapter and a service implementation.

42. A method as recited in claim 41, wherein said service adapter is used to dynamically update said service implementation.

43. A method as recited in claim 36, wherein said at least one desired service is a service discovered and advertised by a second device.

44. A method as recited in claim 36, wherein said at least one desired service is provided by a network component.

45. A system for a first device to discover at least one service available from a second device, said system comprising:

second device advertising means advertising availability of said at least one service and providing an enhanced service descriptor for said at least one service, said enhanced descriptor providing information regarding the location of code for implementing said at least one service;

first device listening means for discovering availability of said at least one service and for receiving said at least one service descriptor; and

means for implementing lazy loading for said at least one service, including means for loading code for said at least one service when said at least one service is referenced by said first device.

46. A system as recited in claim 45, further comprising means for employing a multicast messaging protocol.

47. A system as recited in claim 45, wherein the first device listening means includes means for employing an optional service.

48. A system as recited in claim 45, further comprising means for employing the Java language.

49. A system as recited in claim 45, wherein said at least one service is code running on said second device.

50. A system as recited in claim 45, further comprising said first device and said second device participating in a network.

51. A system as recited in claim 45, further comprising means for running code for said at least one service.

52. A system as recited in claim 51, further comprising means for removing said service descriptor of said at least one service upon receiving a removal command.

53. A system as recited in claim 45, wherein the second device advertising means performs advertising according to an advertising policy.

54. A system as recited in claim 45, wherein said at least one service includes a local service.

55. A system as recited in claim 45, wherein the first device listening means includes means for accepting and storing the service descriptor.

56. A system as recited in claim 45, wherein said second device advertises said at least one service on behalf of a third device.

57. A system as recited in claim 56, wherein said third device is a PDA.

58. A system as recited in claim 45, further comprising second device listening means co-located with said second device advertising means, said second device listening means for discovering availability of at least one particular service from another device.

59. A system as recited in claim 58, wherein said another device is said first device.

60. A system as recited in claim 58, further comprising first device advertisement means co-located with said first device listening means, said first device advertisement means for advertising availability of at least one specific service from a specific device.

61. A system as recited in claim 60, wherein said specific device is said second device.

62. A system as recited in claim 45, further comprising a first device service adapter coupled between said at least one service implementation and at least one application included in said first device.

63. A system as recited in claim 62, wherein said service adapter enables a utility taken from the group consisting of:

security functions, updating functions, load balancing functions, hot swapp functions, language utility and any combinations of these utilities.

64. A system as recited in claim 45, further comprising filtering means for filtering said service descriptor.

65. A system as recited in claim 45, further comprising means for implementing life-cycle management of said at least one service for performing a function from a group consisting of:

registration, look-up, binding, removal, update and any combination of these functions.

66. An apparatus comprising:

a service framework module which includes;

a listener service module to discover at least one service available from a first device and to receive an enhanced descriptor for each said at least one service, said enhanced descriptor providing information regarding the location of code for implementing said at least one service;

a service registry to store each said descriptor; and

means for implementing lazy loading for said at least one service, including means for loading code for said at least one service when said at least one service is referenced by said first device.

67. A system as recited in claim 66, further comprising an application manager to manage a life cycle of at least one application which employs one service included in said at least one service.

68. An apparatus comprising a service framework module which includes an advertising module to advertise said at least one service for the listener module of claim 66.

69. An article of manufacture comprising a computer usable medium having computer readable program code means embodied therein for causing a first device to discover at least one service available from a second device, the computer readable program code means in said article of manufacture comprising computer readable program code means for causing a computer to effect:

said first device listening for availability of at least one service from said second device;

said second device advertising availability of said at least one service and providing an enhanced service descriptor for said at least one service, said enhanced descriptor providing information regarding the location of code for implementing said at least one service;

said first device receiving said at least one service descriptor; and

implementing lazy loading for said at least one service, including loading code for said at least one service when said at least one service is referenced by said first device.

70. An article of manufacture as recited in claim 69, wherein said service descriptor is an enhanced descriptor.

71. An article of manufacture as recited in claim 69, the computer readable program code means in said article of manufacture further comprising computer readable program code means for causing a computer to effect implementing lazy loading for said at least one service.

72. A computer program product comprising a computer usable medium having computer readable program code means embodied therein for causing a first device to discover at least one available service, the computer readable program code means in said computer program product comprising computer readable program code means for causing a computer to effect:

employing a service framework defining and providing life-cycle management of at least one service running on at least a single device;

distributively discovering at least one desired service from said at least one service among devices in an ad-hoc network, said service having an enhanced discriptor associated with said service, said enhanced descriptor providing information regarding the location of code for implementing said at least one service; and

implementing lazy loading for said at least one service, said lazy loading including loading code for said at least one service when said at least one service is referenced by said first device.

73. A program storage device readable by machine, tangibly embodying a program of instructions executable by the machine to perform method steps for a first device to discover at least one service available from a second device, said method steps comprising:

said first device listening for availability of at least one service from said second device;

said second device advertising availability of said at least one service and providing an enhanced service descriptor for said at least one service, said enhanced descriptor providing information regarding the location of code for implementing said at least one service;

said first device receiving said at least one service descriptor; and

implementing lazy loading for said at least one service, including loading code for said at least one service when said at least one service is referenced by said first device.

74. A program storage device readable by machine as recited in claim 73, said method steps further comprising running the code for said at least one service.

75. A program storage device readable by machine as recited in claim 74, said method steps further comprising removing said service descriptor of said at least one service upon receiving a removal command.