Method and apparatus for manipulating mutexes on network assets

• US 6,105,057 A
• Filed: 01/28/1998
• Issued: 08/15/2000
• Est. Priority Date: 01/28/1998
• Status: Expired due to Term

• Current Assignee: Optis Wireless Technology, LLC (Brevet Capital)
• Original Assignee: Ericsson, Inc. (Telefonaktiebolaget LM Ericsson)
• Inventors: Wright, Stephen, Lam, Cory, Kuftedjian, Ohaness
• Primary Examiner(s): VU, VIET DUY
• Application Number:
  US09/014,504
• Time in Patent Office: 930 Days
• Field of Search: 709/102, 709/103, 709/104, 709/107, 709/202, 709/203, 709/213, 709/214, 709/215, 709/216, 709/217, 709/219, 709/223, 709/225, 709/226, 707/9, 707/10, 707/100, 707/104, 707/200, 707/201, 711/147, 711/150, 711/151, 711/152, 711/155, 711/158
• US Class Current: 709/213
• CPC Class Codes: G06F 9/526 Mutual exclusion algorithms
• CPC Class Codes: Y10S 707/99945 Object-oriented database structure processing
• CPC Class Codes: Y10S 707/99948 Application of database or data structure, e.g. distributed, multimedia, or image

Abstract

A system and technique enables network level locks, called network mutexes, on network objects such as databases and ports. A remote data server (RDS) element resides on a server for receiving network mutex (NM) request from remote clients. A NM request includes, in part, a network mutex name, a locking priority, identification of the requesting element and client, and an indication as to whether the network mutex may be shared with other equivalent applications or elements. The RDS element grants the NM request when no other application or element has established the network mutex or the network mutex is held by an equivalent application or element and is in a sharable status. Network mutexes are removed when the remote locking client transmits a NM unlock request. Network mutexes enable central control of the locking and unlocking of network objects.

Claims

1. A method in a computer network system for locking network assets, comprising the steps of:

formulating, at a client, a network mutex (NM) request, wherein a lock on a network asset is requested;

transmitting said NM request from said client to a server;

determining whether said network asset may be locked in response to said NM request;

locking said network asset in response to the determination; and

wherein the step of determining further comprises the steps of;

determining whether an existing NM software module is of a substantially similar type to a requesting software module and whether a sharable option is enabled for the existing NM; and

incrementing a reference counter if said existing NM software module is of a substantially similar type to said requesting software module and said sharable option is enabled for the existing NM.

2. The method of claim 1, wherein the step of formulating further comprises the step of:

including information identifying a specific NM of said network asset in said NM request.

3. The method of claim 2, wherein the step of formulating further comprises the step of:

including a locking priority in said NM request.

4. The method of claim 2, wherein the step of formulating further comprises the steps of:

formulating said NM request at a software module; and

including an indication in said NM request of whether said specific NM is sharable by other software modules of a substantially type similar to said software module.

5. The method of claim 1, wherein the step of determining further comprises the steps of:

determining whether the NM already exists for said network asset; and

creating the NM for said network asset if the NM does not already exist for said network asset.

6. The method of claim 1, wherein the step of determining further comprises the steps of:

determining whether an existing NM software module is identical to a requesting software module; and

sending a success message to said client if said existing NM software module is identical to said requesting software module.

7. The method of claim 1, wherein the step of determining further comprises the step of:

determining whether a first priority of a requesting software module is higher than a second priority of an existing NM software module.

17. The method of claim 1, wherein said network asset comprises at least one of an entire database server and a communications port.

18. The method of claim 1, wherein said NM request comprises at least one of a logged-in user identification and a logged-in user name.

19. The method of claim 1, further including the step of:

automatically unlocking said network asset if said client crashes or disconnects without requesting that said network asset be unlocked.

8. A method in a computer network system for locking network assets, comprising the steps of:

formulating, at a client, a network mutex (NM) request, wherein a lock on a network asset is requested;

transmitting said NM request from said client to a server;

determining whether said network asset may be locked in response to said NM request;

locking said network asset in response to the determination; and

wherein the step of locking further comprises the steps of;

if a first priority of a requesting software module is higher than a second priority of an existing NM software module, unlocking the existing NM of said existing NM software module;

creating the NM for said requesting software module; and

sending a success message to said client.

20. The method of claim 8, wherein said client comprises a computer program application.

9. A method in a computer network system for locking network assets, comprising the steps of:

formulating, at a client, a network mutex (NM) request, wherein a lock on a network asset is requested;

transmitting said NM request from said client to a server;

determining whether said network asset may be locked in response to said NM request;

locking said network asset in response to the determination; and

further including the step of;

sending a failure message to said client if a first priority of said client is not higher than a second priority of an existing NM.

21. The method of claim 9, wherein said failure message includes an indication as to which client is associated with said existing NM.

10. A method in a computer network system for unlocking network assets, comprising the steps of:

formulating, at a client, a network mutex (NM) unlock request, wherein a lock on a network asset is requested to be relinquished;

transmitting said NM unlock request from said client to a server;

processing said NM unlock request to determine whether said lock on said network asset may be relinquished;

releasing said network asset in response to the determination;

wherein the step of processing further includes the step of;

determining whether the NM already exists for said network asset and, if so, whether an existing NM software module is of identical or of substantially similar type to a requesting software module; and

wherein the step of processing still further includes the step of;

sending a failure message to said client if said existing NM software module is neither of identical or of substantially similar type to said requesting software module.

11. A method in a computer network system for controlling network assets, comprising the steps of:

formulating, at a client, a network mutex (NM) request, wherein control of a network asset is requested;

transmitting said NM request from said client to a server;

determining whether said network asset may be controlled in response to said NM request;

enabling control of said network asset to said client in response to the determination; and

wherein the step of determining further comprises the steps of;

comparing an existing NM software module with a requesting software module to determine whether said existing NM software module and said requesting software module are of substantially similar type;

checking a sharable option to determine whether the NM may be shared by software modules of substantially similar types; and

incrementing a reference counter if said existing NM software module is of a substantially similar type to said requesting software module and the NM may be shared by software modules of substantially similar types.

12. The method of claim 11, wherein said control further includes the ability to lock said network asset.

14. The method of claim 11, wherein said control further includes the ability to unlock said network asset.

15. The method of claim 14, wherein the step of determining further comprises the steps of:

ascertaining the identity of an existing NM software module to determine whether the NM is controlled by an unlock requesting software module; and

removing said unlock requesting software module from the NM if the NM is controlled by said unlock requesting software module.

13. A method in a computer network system for controlling network assets, comprising the steps of:

formulating, at a client, a network mutex (NM) request, wherein control of a network asset is requested;

transmitting said NM request from said client to a server;

determining whether said network as set may be controlled in response to said NM request;

enabling control of said network asset to said client in response to the determination;

wherein said control further includes the ability to lock said network asset; and

wherein the step of determining further comprises the steps of;

comparing a first priority of an existing NM software module and a second priority of a requesting software module to determine whether said second priority is greater than said first priority; and

withdrawing control of said network asset from said existing NM software module if said second priority is greater than said first priority.

22. The method of claim 13, wherein said client comprises a computer program application.

16. A computer program product comprising at least one electronically-accessible medium having electronically-implementable instructions thereon, said electronically-implementable instructions causing one or more elements of a computer network to implement the steps of:

formulating, at a client, a network mutex (NM) request, wherein a lock on a network asset is requested;

transmitting said NM request from said client to a server;

determining whether said network asset may be locked in response to said NM request;

locking said network asset in response to the determination; and

wherein the step of determining further comprises the steps of;

determining whether an existing NM software module is of a substantially similar type to a requesting software module and whether a sharable option is enabled for the existing NM; and

incrementing a reference counter if said existing NM software module is of a substantially similar type to said requesting software module and said sharable option is enabled for the existing NM.

23. A method for manipulating network-level locks in a network having network elements of differing priority levels, comprising the steps of:

requesting, by a first network element having a first priority, a first lock on a network-level asset;

establishing said first lock on said network-level asset responsive to said step of requesting by said first network element;

requesting, by a second network element having a second priority, a second lock on said network-level asset, said second priority being higher than said first priority;

unlocking said first lock on said network-level asset responsive to said step of requesting by said second network element and to said second priority being higher than said first priority; and

establishing said second lock on said network-level asset.

24. The method of claim 23, wherein said first and second network elements each comprise at least one of a computer program application, a computer terminal, and a user identification.