Message-based leasing of resources in a distributed computing environment

• US 6,917,976 B1
• Filed: 08/31/2000
• Issued: 07/12/2005
• Est. Priority Date: 05/09/2000
• Status: Expired due to Term

• Current Assignee: Oracle America, Inc. (Oracle Corporation)
• Original Assignee: Sun Microsystems Incorporated (Oracle Corporation)
• Inventors: Slaughter, Gregory L., Saulpaugh, Thomas E., Traversat, Bernard A., Duigou, Michael J.
• Primary Examiner(s): Cuchlinski, Jr., William A.
• Assistant Examiner(s): MANIWANG, JOSEPH R
• Application Number:
  US09/653,216
• Time in Patent Office: 1,776 Days
• Field of Search: 709/226, 709/203, 709/227, 707/10
• US Class Current: 709/226
• CPC Class Codes: G06F 16/951 Indexing; Web crawling techniques
• CPC Class Codes: G06F 16/9537 Spatial or temporal dependent retrieval, e.g. spatiotemporal queries
• CPC Class Codes: G06F 16/9566 URL specific, e.g. using aliases, detecting broken or misspelled links
• CPC Class Codes: G06F 2209/544 Remote
• CPC Class Codes: G06F 9/465 Distributed object oriented systems remote method invocation [RMI] G06F9/548
• CPC Class Codes: G06F 9/5061 Partitioning or combining of resources
• CPC Class Codes: G06F 9/542 Event management; Broadcasting; Multicasting; Notifications
• CPC Class Codes: G06Q 30/02 Marketing; Price estimation or determination; Fundraising
• CPC Class Codes: G06Q 30/06 Buying, selling or leasing transactions
• CPC Class Codes: H04L 41/0681 Configuration of triggering conditions
• CPC Class Codes: H04L 41/22 comprising specially adapted graphical user interfaces [GUI]
• CPC Class Codes: H04L 41/5054 Automatic deployment of services triggered by the service manager, e.g. service implementation by automatic configuration of network components
• CPC Class Codes: H04L 67/02 based on web technology, e.g. hypertext transfer protocol [HTTP]
• CPC Class Codes: H04L 67/04 specially adapted for terminals or networks with limited capabilities; specially adapted for terminal portability
• CPC Class Codes: H04L 67/1001 for accessing one among a plurality of replicated servers
• CPC Class Codes: H04L 67/303 Terminal profiles
• CPC Class Codes: H04L 67/306 User profiles
• 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
• CPC Class Codes: H04L 67/52 specially adapted for the location of the user terminal
• CPC Class Codes: H04L 67/53 : using third party service providers
• CPC Class Codes: H04L 69/329 : in the application layer [OSI layer 7]
• CPC Class Codes: H04W 72/00 : Local resource management
• CPC Class Codes: Y10S 707/99939 : Privileged access

Abstract

A system and method for providing message-based leasing of resources in a distributed computing environment. Services may issue leases to clients and provide operations on those leases. The lease functionality of a service may be defined in an XML message schema. Gates may be used to perform lease operations. Leases may be granted for a period that may be negotiated. Leasing messages for performing leasing operations may be defined. The leasing messages may include messages to renew a lease and to cancel a lease. Services may specify an address where leasing messages may be sent. A lease renewal mechanism may be provided in which a gate may receive lease renewal messages and automatically respond to them. A mechanism to detect stale advertisements in a space may be provided. When a service publishes its advertisement in a space, the service obtains a lease on the publishing of its advertisement. Each advertisement may include a time by which the service may renew the advertisement. When the lease is not renewed, the space service marks the service advertisement as stale. Services renew advertisements by sending a renewal message to the space. Stale service advertisements may be deleted after a period. A space service may allow clients to lease service advertisements in the space to thus grant clients access to the services. Messages are described for accessing the leasing services provided by the space services.

Claims

1. A method for managing resources provided by services in a distributed computing environment, comprising:

receiving from a client a service request message in a data representation language referencing a resource provided by a service, wherein said service request message specifies a first requested lease period;

granting access to said referenced resource for a first granted lease period; and

sending a service request response message in said data representation language advising said client of said first granted lease period.

2. The method as recited in claim 1, wherein said receiving, said granting, and said sending are performed by said service.

3. The method as recited in claim 1,

wherein said receiving a service request message and said sending a service request response message are performed by a space service, wherein said space service comprises a plurality of service advertisements for enabling access by clients to resources provided by a plurality of services including said service;

and

wherein said space service obtains said first granted lease period from said service on behalf of said client.

4. The method as recited in claim 1,

wherein said service comprises a service process and a service message endpoint operatively coupled to said service process and operable to receive request messages from and send response messages to said client in said data representation language;

and

wherein said receiving a service request message and said sending a service request response message are performed by said service message endpoint on behalf of said service process.

5. The method as recited in claim 1, further comprising:

receiving from said client, prior to said first granted lease period expiring, a lease renewal message in said data representation language referencing said resource provided by said service, wherein said lease renewal message specifies a second requested lease period;

granting access to said referenced resource for a second granted lease period; and

sending a lease renewal response message in said data representation language advising said client of said second granted lease period.

6. The method as recited in claim 1, further comprising:

receiving from said client a lease cancel message in said data representation language referencing said resource; and

terminating said first granted lease period for accessing said resource in response to said receiving a lease cancel message.

7. The method as recited in claim 6, further comprising sending a lease cancel acknowledgment message in said data representation language advising said first granted lease period for accessing said resource is terminated.

8. The method as recited in claim 1, further comprising providing to said client an address for sending data representation language messages for managing leases of resources provided by said service.

9. The method as recited in claim 8, wherein said service request message is received by said service at said address provided to said client.

10. The method as recited in claim 8, wherein said address is a Uniform Resource Identifier (URI).

11. The method as recited in claim 1, further comprising terminating said granted access when said first granted lease period expires.

12. The method as recited in claim 1, wherein said data representation language is eXtensible Markup Language (XML).

13. The method as recited in claim 1, wherein said first granted lease period is less than or equal to said first requested lease period.

14. A method for accessing resources provided by services in a distributed computing environment, comprising:

a client sending a service request message in a data representation language referencing a resource provided by a service, wherein said service request message specifies a first requested lease period;

said client receiving a service request response message in said data representation language, wherein said service request response message includes a first granted lease period for accessing said resource.

15. The method as recited in claim 14, wherein said client sends said service request message to said service, and wherein said client receives said service request response message from said service.

16. The method as recited in claim 14,

wherein said client sends said service request message to a space service, wherein said space service comprises a plurality of service advertisements for enabling access by clients to resources provided by a plurality of services including said service;

wherein said space service obtains said first granted lease period from said service on behalf of said client; and

wherein said client receives said service request response message from said space service.

17. The method as recited in claim 14,

wherein said client comprises a client process and a client message endpoint operatively coupled to said client process and operable to send request messages to and receive response messages from said service in said data representation language;

and

wherein said client sending said service request message and said client receiving said service request response message are performed by said client message endpoint on behalf of said client process.

18. The method as recited in claim 14, further comprising:

said client sending, prior to said first granted lease period expiring, a lease renewal message in said data representation language referencing said resource provided by said service, wherein said lease renewal message specifies a second requested lease period;

said client receiving a lease renewal response message in said data representation language, wherein said lease renewal response message includes a second granted lease period for accessing said resource.

19. The method as recited in claim 14, further comprising:

said client sending a lease cancel message in said data representation language referencing said resource, wherein said lease cancel message terminates said first granted lease period for accessing said resource; and

said client receiving a lease cancel acknowledgment message in said data representation language acknowledging said first granted lease period for accessing said resource is terminated.

20. The method as recited in claim 14, further comprising:

said client accessing a service advertisement for enabling access by clients to resources provided by said service, said service advertisement comprising;

a data representation language message schema comprising descriptions of data representation language messages for managing leases of resources provided by said service; and

an address for said service receiving said data representation language messages for managing leases of resources provided by said service.

21. The method as recited in claim 20, further comprising said client generating said service request message in accordance with a description of said service request message comprised in said descriptions of data representation language messages for managing leases of resources.

22. The method as recited in claim 20, wherein said service request message is sent by said client to said address for said service receiving said data representation language messages.

23. The method as recited in claim 20, wherein said address is a Uniform Resource Identifier (URI).

24. The method as recited in claim 14, wherein said data representation language is eXtensible Markup Language (XML).

25. A method for managing resources provided for clients by services in a distributed computing environment, comprising:

granting to a client access to a resource provided by a service for a first granted lease period;

receiving, prior to said first granted lease period expiring, a lease renewal message in a data representation language referencing said resource provided by said service, wherein said lease renewal message specifies a second requested lease period; and

granting access to said referenced resource for a second granted lease period.

26. The method as recited in claim 25, further comprising sending a lease renewal response message in said data representation language advising said client of said second granted lease period.

27. The method as recited in claim 25, wherein said client comprises a client process and a client message endpoint operatively coupled to said client process and operable to send request messages to and receive response messages from said service in said data representation language, the method further comprising:

said client message endpoint sending said lease renewal message to said service on behalf of said client process.

28. The method as recited in claim 25, further comprising:

receiving a lease cancel message in said data representation language referencing said resource; and

terminating said second granted lease period for accessing said resource in response to said receiving a lease cancel message.

29. The method as recited in claim 28, further comprising:

sending a lease cancel acknowledgment message in said data representation language advising said second granted lease period for accessing said resource is terminated.

30. The method as recited in claim 25, wherein said granting access to said resource for said first granted lease period comprises:

receiving a service request message in said data representation language referencing said resource provided by said service, wherein said service request message specifies a first requested lease period;

sending a service request response message in said data representation language, wherein said service request response message includes said first granted lease period for accessing said resource.

31. The method as recited in claim 25, wherein said second granted lease period is less than or equal to said second requested lease period.

32. The method as recited in claim 25, wherein said data representation language is extensible Markup Language (XML).

33. A method for managing resources provided for clients by services in a distributed computing environment, comprising:

a first client sending a first service request message in a data representation language referencing a resource provided by a service, wherein said first service request message specifies a first requested lease period;

said service receiving said first service request message;

said service granting to said first client access to said referenced resource for a first granted lease period;

said service sending a service request response message in said data representation language advising said first client of said first granted lease period; and

said first client receiving said service request response message, wherein said service request response message includes said first granted lease period for accessing said resource.

34. The method as recited in claim 33, further comprising:

said first client sending, prior to said first granted lease period expiring, a lease renewal message in said data representation language referencing said resource provided by said service, wherein said lease renewal message specifies a second requested lease period;

said service receiving, prior to said first granted lease period expiring, said lease renewal message;

said service granting access to said referenced resource for a second granted lease period;

said service sending a lease renewal response message in said data representation language advising said first client of said second granted lease period; and

said first client receiving said lease renewal response message, wherein said lease renewal response message includes said second granted lease period for accessing said resource.

35. The method as recited in claim 33, further comprising:

a second client sending a second service request message in said data representation language referencing said resource provided by said service, wherein said second service request message specifies a third requested lease period;

said service receiving said second service request message;

said service granting, prior to said first granted lease period expiring, to said second client access to said referenced resource for a third granted lease period;

wherein said first granted lease period and said second granted lease period at least partially overlap.

36. The method as recited in claim 33, wherein said data representation language is eXtensible Markup Language (XML).

37. A method for managing service advertisements for accessing resources provided by services in a distributed computing environment, comprising:

a space service receiving a publish advertisement lease request message in a data representation language referencing a service advertisement for a service, wherein said publish advertisement lease request message specifies a first requested publishing lease period; and

said space service granting publishing of said service advertisement for a first granted publishing lease period;

wherein said space service comprises a plurality of service advertisements, wherein each service advertisement comprises information to enable access by clients to resources provided by a corresponding service.

38. The method as recited in claim 37, wherein, during said granted publishing lease period, said service advertisement of said service is accessible to clients of said space service, and wherein resources of said service are accessible to said clients of said space service by accessing said service advertisement.

39. The method as recited in claim 37, further comprising:

said space service sending a publish advertisement lease request response message in said data representation language advising said service of said first granted publishing lease period.

40. The method as recited in claim 37, further comprising:

said space service receiving, prior to said first granted publishing lease period expiring, a publish advertisement lease renewal message in said data representation language referencing said service advertisement provided by said service, wherein said publish advertisement lease response message specifies a second requested publishing lease period;

said space service granting publishing of said service advertisement for a second granted publishing lease period; and

said space service sending a publish advertisement lease renewal response message in said data representation language advising said service of said second granted publishing lease period.

41. The method as recited in claim 37, further comprising said space service marking as stale said service advertisement when said first granted lease period expires.

42. The method as recited in claim 41, further comprising said space service prohibiting access by clients to said stale service advertisement.

43. The method as recited in claim 41, further comprising:

said space service receiving a publish advertisement lease renewal message in said data representation language referencing said service advertisement provided by said service, wherein said publish advertisement lease renewal message specifies a second requested publishing lease period;

said space service granting publishing of said service advertisement for a second granted publishing lease period; and

said space service removing said marking as stale of said service advertisement thus allowing access by clients to said service advertisement.

44. The method as recited in claim 41, further comprising removing said service advertisement from said space service subsequent to said marking said service advertisement as stale.

45. The method as recited in claim 44, further comprising said space service determining that said service advertisement has been marked as stale for at least a maximum allowed period for said service advertisement to remain on said space service while marked as stale, wherein said removing said service advertisement from said space service is performed in response to said determining.

46. The method as recited in claim 37, further comprising:

said space service receiving an unpublish advertisement lease message in said data representation language referencing said service advertisement; and

said space service unpublishing said service advertisement in response to said receiving an unpublish advertisement lease message.

47. The method as recited in claim 37, further comprising:

said space service receiving a space service request message in said data representation language referencing said service advertisement for said service, wherein said space service request message specifies a first requested lease period for a first client;

said space service granting to said first client access to said service advertisement for a first granted lease period; and

said space service sending a space service request response message in said data representation language advising said first client of said first granted lease period.

48. The method as recited in claim 47, further comprising said first client accessing of one or more resources of said service specified in said service advertisement, wherein said one or more resources are accessible to said first client in accordance with service resource access information comprised in said service advertisement.

49. The method as recited in claim 48, wherein said service resource access information comprises descriptions of one or more data representation language messages for accessing said resources.

50. The method as recited in claim 48, wherein said service resource access information comprises one or more Uniform Resource Identifiers (URIs) for accessing said resources.

51. The method as recited in claim 47, further comprising:

said space service receiving, prior to said first granted lease period expiring, a lease renewal message in said data representation language referencing said service advertisement, wherein said lease renewal message specifies a second requested lease period;

said space service granting to said first client access to said service advertisement for a second granted lease period; and

said space service sending a lease renewal response message in said data representation language advising said first client of said second granted lease period.

52. The method as recited in claim 47, further comprising:

said space service receiving a second service request message in said data representation language referencing said service advertisement for said service, wherein said second service request message specifies a third requested lease period for a second client; and

said space service granting, prior to said first granted lease period expiring, to said second client access to said service advertisement for a third granted lease period;

wherein said first granted lease period and said second granted lease period at least partially overlap.

53. The method as recited in claim 37, wherein said first granted publishing lease period is less than or equal to said first requested publishing lease period.

54. The method as recited in claim 37, wherein said data representation language is extensible Markup Language (XML).

55. A method for managing service advertisements for accessing resources provided by services in a distributed computing environment, comprising:

a space service publishing a service advertisement for a service for a first granted publishing lease period;

wherein said space service comprises a plurality of service advertisements, wherein each service advertisement comprises information to enable access by clients to resources provided by a corresponding service;

wherein, during said granted publishing lease period, said service advertisement of said service is accessible to clients of said service; and

said space service marking as stale said service advertisement when said first granted lease period expires, wherein said space service prohibits access by clients to said service advertisement marked as stale.

56. The method as recited in claim 55, further comprising:

said space service receiving a publish advertisement lease renewal message in said data representation language referencing said service advertisement provided by said service, wherein said publish advertisement lease renewal message specifies a second requested publishing lease period;

said space service granting publishing of said service advertisement for a second granted publishing lease period; and

said space service removing said marking as stale of said service advertisement thus allowing access by clients to said service advertisement.

57. The method as recited in claim 55, further comprising removing said service advertisement from said space service subsequent to said marking said service advertisement as stale.

58. The method as recited in claim 57, further comprising said space service determining that said service advertisement has been marked as stale for at least a maximum allowed period for said service advertisement to remain on said space service while marked as stale, wherein said removing said service advertisement from said space service is performed in response to said determining.

59. A distributed computing system, comprising:

a client device; and

a service device comprising a service process executable within said service device, wherein the service device is configured to;

receive from said client device a service request message in a data representation language referencing a resource provided by said service process, wherein said service request message specifies a first requested lease period;

grant access to said referenced resource for a first granted lease period; and

send a service request response message in said data representation language advising said client device of said first granted lease period.

60. The system as recited in claim 59, wherein said receiving, said granting, and said sending are performed by said service process.

61. The system as recited in claim 59,

wherein said service device is a space service device further comprising:

a space service process executable within said space service device; and

a plurality of service advertisements for enabling access by client devices to resources provided by a plurality of service processes including said service process;

wherein said receiving a service request message and said sending a service request response message are performed by said space service process; and

wherein said space service process is further configured to obtain said first granted lease period from said service process on behalf of said client device.

62. The system as recited in claim 59,

wherein said service device further comprises a service message endpoint operatively coupled to said service process and operable to receive request messages from and send response messages to said client device in said data representation language;

and

wherein said receiving a service request message and said sending a service request response message are performed by said service message endpoint on behalf of said service process.

63. The system as recited in claim 59, wherein the service device is further configured to:

receive from said client device, prior to said first granted lease period expiring, a lease renewal message in said data representation language referencing said resource provided by said service process, wherein said lease renewal message specifies a second requested lease period;

grant access to said referenced resource for a second granted lease period; and

send a lease renewal response message in said data representation language advising said client device of said second granted lease period.

64. The system as recited in claim 59, wherein the service device is further configured to:

receive from said client device a lease cancel message in said data representation language referencing said resource; and

terminate said first granted lease period for accessing said resource in response to said receiving a lease cancel message.

65. The system as recited in claim 59,

wherein the service device further comprises a Uniform Resource Identifier (URI) for sending data representation language messages for managing leases of resources provided by said service process;

wherein the service device is further configured to provide said URI to said client device; and

wherein said service request message is received by said service process at said URI.

66. The system as recited in claim 59, wherein said data representation language is eXtensible Markup Language (XML).

67. A distributed computing system, comprising:

a client device; and

a service device, wherein the service device is configured to;

grant to said client device access to a resource provided by said service device for a first granted lease period;

receive, prior to said first granted lease period expiring, a lease renewal message in a data representation language referencing said resource provided by said service device, wherein said lease renewal message specifies a second requested lease period; and

grant access to said referenced resource for a second granted lease period.

68. The system as recited in claim 67, wherein the service device is further configured to send a lease renewal response message in said data representation language advising said client device of said second granted lease period.

69. The system as recited in claim 67, wherein said client device comprises:

a client process executable within said client device; and

a client message endpoint executable within said client device and operatively coupled to said client process, wherein said client message endpoint is configured to send request messages to and receive response messages from said service device in said data representation language, wherein said client message endpoint is further configured to;

send said lease renewal message to said service device on behalf of said client process.

70. The system as recited in claim 67, wherein the service device is further configured to:

receive a lease cancel message in said data representation language referencing said resource; and

terminate said second granted lease period for accessing said resource in response to said receiving a lease cancel message.

71. The system as recited in claim 67, wherein, in said granting access to said resource for said first granted lease period, the service device is further configured to:

receive a service request message in said data representation language referencing said resource provided by said service device, wherein said service request message specifies a first requested lease period; and

send a service request response message in said data representation language, wherein said service request response message includes said first granted lease period for accessing said resource.

72. The system as recited in claim 67, wherein said data representation language is extensible Markup Language (XML).

73. A distributed computing system, comprising:

a service device configured to provide resources to clients;

a space service device configured to store one or more service advertisements, wherein each service advertisement comprises information to enable access by clients to resources provided by a corresponding service device, and wherein the space service device comprises a service advertisement corresponding to said service device; and

wherein said space service device is configured to;

receive a publish advertisement lease request message in a data representation language referencing said service advertisement corresponding to said service device, wherein said publish advertisement lease request message specifies a first requested publishing lease period; and

grant publishing of said service advertisement for a first granted publishing lease period;

wherein, during said granted publishing lease period, said service advertisement of said service device is accessible to clients of said space service device, and wherein resources of said service device are accessible to said clients of said space service device by accessing said service advertisement.

74. The system as recited in claim 73, wherein said space service device is further configured to send a publish advertisement lease request response message in said data representation language advising said service device of said first granted publishing lease period.

75. The system as recited in claim 73, wherein said space service device is further configured to:

receive, prior to said first granted publishing lease period expiring, a publish advertisement lease renewal message in said data representation language referencing said service advertisement provided by said service device, wherein said publish advertisement lease response message specifies a second requested publishing lease period;

grant publishing of said service advertisement for a second granted publishing lease period; and

send a publish advertisement lease renewal response message in said data representation language advising said service device of said second granted publishing lease period.

76. The system as recited in claim 73, wherein said space service device is further configured to:

mark as stale said service advertisement when said first granted lease period expires; and

prohibit access by clients to said stale service advertisement.

77. The system as recited in claim 76, wherein said space service device is further configured to:

receive a publish advertisement lease renewal message in said data representation language referencing said service advertisement provided by said service device, wherein said publish advertisement lease renewal message specifies a second requested publishing lease period;

grant publishing of said service advertisement for a second granted publishing lease period; and

remove said marking as stale of said service advertisement thus allowing access by clients to said service advertisement.

78. The system as recited in claim 76, wherein said space service device is further configured to:

determine that said service advertisement has been marked as stale for at least a maximum allowed period for said service advertisement to remain on said space service device while marked as stale; and

remove said service advertisement from said space service device in response to said determining.

79. The system as recited in claim 73, wherein said space service device is further configured to:

receive an unpublish advertisement lease message in said data representation language referencing said service advertisement; and

unpublish said service advertisement in response to said receiving an unpublish advertisement lease message.

80. The system as recited in claim 73, further comprising:

a first client device; and

wherein said space service device is further configured to;

receive a space service request message in said data representation language referencing said service advertisement corresponding to said service device, wherein said space service request message specifies a first requested lease period for said first client device;

grant to said first client device access to said service advertisement for a first granted lease period; and

send a space service request response message in said data representation language advising said first client device of said first granted lease period.

81. The system as recited in claim 80, wherein said first client device is configured to access one or more resources of said service device specified in said service advertisement, wherein said one or more resources are accessible to said first client device in accordance with service resource access information comprised in said service advertisement, wherein said service resource access information comprises:

descriptions of one or more data representation language messages for accessing said resources; and

one or more Uniform Resource Identifiers (URIs) for accessing said resources of said service device.

82. The system as recited in claim 80, wherein the space service device is further configured to:

receive, prior to said first granted lease period expiring, a lease renewal message in said data representation language referencing said service advertisement, wherein said lease renewal message specifies a second requested lease period;

grant to said first client device access to said service advertisement for a second granted lease period; and

send a lease renewal response message in said data representation language advising said first client device of said second granted lease period.

83. The system as recited in claim 80, further comprising:

a second client device; and

wherein the space service device is further configured to;

receive a second service request message in said data representation language referencing said service advertisement for said service device, wherein said second service request message specifies a third requested lease period for said second client device; and

grant, prior to said first granted lease period expiring, to said second client device access to said service advertisement for a third granted lease period;

wherein said first granted lease period and said second granted lease period at least partially overlap.

84. The system as recited in claim 73, wherein said data representation language is eXtensible Markup Language (XML).

85. A distributed computing system, comprising:

a service device configured to provide resources to clients;

a space service device configured to store one or more service advertisements, wherein each service advertisement comprises information to enable access by clients to resources provided by a corresponding service device, and wherein the space service device comprises a service advertisement corresponding to said service device; and

wherein said space service device is configured to;

publish a service advertisement for said service device for a first granted publishing lease period, wherein, during said granted publishing lease period, said service advertisement of said service is accessible to clients of said service device; and

mark as stale said service advertisement when said first granted lease period expires, wherein said space service device prohibits access by clients to said service advertisement marked as stale.

86. The system as recited in claim 85, wherein the space service device is further configured to:

receive a publish advertisement lease renewal message in said data representation language referencing said service advertisement corresponding to said service device, wherein said publish advertisement lease renewal message specifies a second requested publishing lease period;

grant publishing of said service advertisement for a second granted publishing lease period; and

remove said marking as stale of said service advertisement thus allowing access by clients to said service advertisement.

87. The system as recited in claim 85, wherein the space service device is further configured to remove said service advertisement from said space service device subsequent to said marking said service advertisement as stale.

88. A carrier medium comprising program instructions, wherein the program instructions are computer-executable to implement:

receiving from a client a service request message in a data representation language referencing a resource provided by a service, wherein said service request message specifies a first requested lease period;

granting access to said referenced resource for a first granted lease period; and

sending a service request response message in said data representation language advising said client of said first granted lease period.

89. The carrier medium as recited in claim 88, wherein the program instructions are further computer-executable to implement:

receiving from said client, prior to said first granted lease period expiring, a lease renewal message in said data representation language referencing said resource provided by said service, wherein said lease renewal message specifies a second requested lease period; and

granting access to said referenced resource for a second granted lease period.

90. The carrier medium as recited in claim 88, wherein the program instructions are further computer-executable to implement:

receiving from said client a lease cancel message in said data representation language referencing said resource; and

terminating said first granted lease period for accessing said resource in response to said receiving a lease cancel message.

91. The carrier medium as recited in claim 88, wherein said data representation language is eXtensible Markup Language (XML).

92. A carrier medium comprising program instructions, wherein the program instructions are computer-executable to implement:

granting to a client access to a resource provided by a service for a first granted lease period;

receiving, prior to said first granted lease period expiring, a lease renewal message in a data representation language referencing said resource provided by said service, wherein said lease renewal message specifies a second requested lease period; and

granting access to said referenced resource for a second granted lease period.

93. The carrier medium as recited in claim 92, wherein the program instructions are further computer-executable to implement sending a lease renewal response message in said data representation language advising said client of said second granted lease period.

94. The carrier medium as recited in claim 92, wherein the program instructions are further computer-executable to implement:

receiving a lease cancel message in said data representation language referencing said resource; and

terminating said second granted lease period for accessing said resource in response to said receiving a lease cancel message; and

sending a lease cancel acknowledgment message in said data representation language advising said second granted lease period for accessing said resource is terminated.

95. The carrier medium as recited in claim 92, wherein, in said granting access to said resource for said first granted lease period, the program instructions are further computer-executable to implement:

receiving a service request message in said data representation language referencing said resource provided by said service, wherein said service request message specifies a first requested lease period; and

sending a service request response message in said data representation language, wherein said service request response message includes said first granted lease period for accessing said resource.

96. A carrier medium comprising program instructions, wherein the program instructions are computer-executable to implement:

a space service receiving a publish advertisement lease request message in a data representation language referencing a service advertisement for a service, wherein said publish advertisement lease request message specifies a first requested publishing lease period; and

said space service granting publishing of said service advertisement for a first granted publishing lease period;

wherein said space service comprises a plurality of service advertisements, wherein each service advertisement comprises information to enable access by clients to resources provided by a corresponding service; and

wherein, during said granted publishing lease period, said service advertisement of said service is accessible to clients of said space service, and wherein resources of said service are accessible to said clients of said space service by accessing said service advertisement.

97. The carrier medium as recited in claim 96, wherein the program instructions are further computer-executable to implement:

said space service receiving, prior to said first granted publishing lease period expiring, a publish advertisement lease renewal message in said data representation language referencing said service advertisement provided by said service, wherein said publish advertisement lease response message specifies a second requested publishing lease period;

said space service granting publishing of said service advertisement for a second granted publishing lease period.

98. The carrier medium as recited in claim 96, wherein the program instructions are further computer-executable to implement:

said space service marking as stale said service advertisement when said first granted lease period expires; and

said space service prohibiting access by clients to said stale service advertisement.

99. The carrier medium as recited in claim 96, wherein the program instructions are further computer-executable to implement:

said space service receiving an unpublish advertisement lease message in said data representation language referencing said service advertisement; and

said space service unpublishing said service advertisement in response to said receiving an unpublish advertisement lease message.

100. The carrier medium as recited in claim 96, wherein the program instructions are further computer-executable to implement:

said space service receiving a space service request message in said data representation language referencing said service advertisement for said service, wherein said space service request message specifies a first requested lease period for a first client;

said space service granting to said first client access to said service advertisement for a first granted lease period; and

said space service sending a space service request response message in said data representation language advising said first client of said first granted lease period.

101. The carrier medium as recited in claim 100, wherein the program instructions are further computer-executable to implement:

said space service receiving, prior to said first granted lease period expiring, a lease renewal message in said data representation language referencing said service advertisement, wherein said lease renewal message specifies a second requested lease period;

said space service granting to said first client access to said service advertisement for a second granted lease period; and

said space service sending a lease renewal response message in said data representation language advising said first client of said second granted lease period.

102. The carrier medium as recited in claim 96, wherein said data representation language is eXtensible Markup Language (XML).

103. A carrier medium for managing service advertisements for accessing resources provided by services in a distributed computing environment, comprising:

a space service publishing a service advertisement for a service for a first granted publishing lease period;

wherein said space service comprises a plurality of service advertisements, wherein each service advertisement comprises information to enable access by clients to resources provided by a corresponding service;

wherein, during said granted publishing lease period, said service advertisement of said service is accessible to clients of said service; and

said space service marking as stale said service advertisement when said first granted lease period expires, wherein said space service prohibits access by clients to said service advertisement marked as stale.

104. The carrier medium as recited in claim 103, wherein the program instructions are further computer-executable to implement:

said space service receiving a publish advertisement lease renewal message in said data representation language referencing said service advertisement provided by said service, wherein said publish advertisement lease renewal message specifies a second requested publishing lease period;

said space service granting publishing of said service advertisement for a second granted publishing lease period; and

said space service removing said marking as stale of said service advertisement thus allowing access by clients to said service advertisement.