Method and apparatus for scaling universal plug and play networks using atomic proxy replication

• US 6,571,277 B1
• Filed: 10/19/1999
• Issued: 05/27/2003
• Est. Priority Date: 10/19/1999
• Status: Expired due to Term

• Current Assignee: Google LLC (Alphabet Inc.)
• Original Assignee: International Business Machines Corporation
• Inventors: Graham, Stephen Glen, Daniels-Barnes, Fonda Jonette, Wesley, Ajamu Akinwunmi
• Primary Examiner(s): Sheikh, Ayaz
• Assistant Examiner(s): Zia, Syed
• Application Number:
  US09/420,700
• Time in Patent Office: 1,316 Days
• Field of Search: 709/201, 709/213, 709/214, 709/215, 709/216
• US Class Current: 709/213
• CPC Class Codes: H04L 67/1001 for accessing one among a plurality of replicated servers
• CPC Class Codes: H04L 67/1017 based on a round robin mechanism
• CPC Class Codes: H04L 67/1095 Replication or mirroring of data, e.g. scheduling or transport for data synchronisation between network nodes
• CPC Class Codes: H04L 67/288 Distributed intermediate devices, i.e. intermediate devices for interaction with other intermediate devices on the same level
• CPC Class Codes: H04L 67/51 Discovery or management thereof, e.g. service location protocol [SLP] or web services
• CPC Class Codes: H04L 67/56 Provisioning of proxy services store-and-forward switching systems in data switching networks H04L12/54
• CPC Class Codes: H04L 67/568 Storing data temporarily at an intermediate stage, e.g. caching

Abstract

A method and apparatus in a distributed data processing system for scaling servers. Access to a shared memory for a period of time is selectively provided to a server within a plurality of servers, wherein the shared memory is used by the server to process requests. All other servers within the plurality of servers are prevented from accessing the shared memory during the period of time.

Claims

1. A method comprising:

selectively providing a first service discovery protocol proxy server within a plurality of service discovery protocol proxy servers access to a shared cache for a first period of time, wherein the shared cache is used by the first service discovery protocol proxy server to process requests;

preventing all other service discovery protocol proxy servers within the plurality of service discovery protocol proxy servers from accessing the shared cache during the first period of time; and

allowing a second service discovery protocol proxy server within the plurality of service discovery protocol proxy servers to access the shared cache after the first period of time has elapsed, wherein each of the plurality of service discovery protocol proxy servers is assigned a given period of time for accessing the shared cache.

2. The method of claim 1, wherein the given period of time for accessing the shared cache is equal for each of the plurality of proxy servers.

3. The method of claim 1, wherein the shared cache includes information identifying clients serviced by the plurality of service discovery protocol proxy servers.

4. The method of claim 3, wherein each of the plurality of service discovery protocol proxy servers services requests for a plurality of sets of clients identified by the information and wherein each service discovery protocol proxy server within the plurality service discovery protocol proxy servers services requests from a different set of clients.

5. The method of claim 1, wherein the given period of time for each of the plurality of service discovery protocol proxy servers to access the shared cache is selected using a round-robin scheme.

6. The method of claim 1 further comprising:

allowing a service discovery protocol proxy server access to the shared cache to multicast messages to clients handled by the service discovery proxy server.

7. The method of claim 1, wherein the plurality of service discovery protocol proxy servers is in a universal plug and play network.

8. The method of claim 1, wherein the shared cache includes information identifying clients handled by the plurality of service discovery protocol proxy servers.

9. The method of claim 1, wherein the shared cache includes information identifying services handled by the plurality of service discovery protocol proxy servers.

10. The method of claim 1, wherein the plurality of service discovery protocol proxy servers handle a plurality of clients and wherein each of the plurality of service discovery protocol proxy servers handles a different subset of clients within the plurality of clients.

11. The method of claim 1, wherein the given period of time for accessing the shared cache for each of the plurality of service discovery protocol proxy servers is equal in duration to the given period of time for accessing the shared cache for at least one other of the plurality of service discovery protocol proxy servers.

12. The method of claim 1, further comprising:

servicing a request by the first service discovery protocol proxy server from the shared cache in response to providing the first service discovery protocol server access to the shared cache.

13. The method of claim 1, further comprising:

servicing a remote request via a remote service discovery protocol server in response to preventing the plurality of service discovery protocol proxy servers from accessing the snared cache.

14. The method of claim 1, wherein the plurality of service discovery protocol proxy servers includes at least one Simple Service Discovery Protocol (SSDP) proxy server.

15. A distributed service discovery protocol proxy servicing system comprising:

a network;

a shared cache coupled to the network;

a plurality of service discovery protocol proxy servers coupled to the network, wherein each of the plurality of service discovery protocol proxy servers services requests using the shared cache during a selected period of time during which other service discovery protocol proxy servers within the plurality of service discovery protocol proxy servers are blocked from servicing requests using the stared cache.

16. The distributed service discovery protocol proxy servicing system of claim 15, wherein the selected period of time assigned to each of the plurality of service discovery protocol proxy servers is selected using a round-robin scheme.

17. The distributed service discovery protocol proxy servicing system of claim 15, wherein the plurality of service discovery protocol proxy servers service requests from a set of clients.

18. The distributed service discovery protocol proxy servicing system of claim 17, wherein the plurality of service discovery protocol proxy servers multicast a message to the set of clients, wherein the message contains a unique service name and an address and wherein the unique service name is identical while the address is based on a location of a service discovery protocol proxy server multicasting the message.

19. The distributed service discovery protocol proxy servicing system of claim 15, wherein each of the plurality of service discovery protocol proxy servers services requests for a plurality of sets of clients and wherein each service discovery protocol proxy server within the plurality of service discovery protocol proxy servers services requests from a different set of clients.

20. The distributed service discovery protocol proxy servicing system of claim 19, wherein each of the plurality of service discovery protocol proxy servers multicast a message to a set of clients different from the other service discovery protocol proxy servers within the plurality of service discovery protocol proxy servers, wherein the message contains a unique service name and an address, and wherein the unique service name is identical while the address is based on a location of a service discovery protocol proxy server multicasting the message.

21. The distributed service discovery protocol proxy servicing system of claim 19, wherein the shared cache includes a plurality or sets of information for the plurality of service discovery protocol proxy servers, wherein a set of information within the plurality of sets of information includes clients serviced by a service discovery protocol proxy server associated with the set of information and services managed by the service discovery protocol proxy server.

22. The distributed service discovery protocol proxy servicing system of claim 15 further comprising an aproxy server.

23. The distributed service discovery protocol proxy servicing system of claim 22, wherein the plurality of service discovery protocol proxy servers store processed requests in the shared cache, wherein the aproxy server stores unprocessed requests for services.

24. The distributed service discovery protocol proxy servicing system of claim 23, wherein the aproxy server compares the stored unprocessed requests to the processed requests and services any stored unprocessed requests responsive to the aproxy server being selected to become a service discovery protocol proxy server within the plurality of service discovery protocol proxy servers.

25. The distributed service discovery protocol proxy servicing system of claim 15, wherein the plurality of service discovery protocol proxy servers processes requests from services and clients.

26. The distributed service discovery protocol proxy servicing system of claim 15, wherein the selected period of time is equal for each of the plurality of service discovery protocol proxy servers.

27. The distributed service discovery protocol proxy servicing system of claim 15, wherein the distributed data processing system is a universal plug and play network.

28. The system of claim 15, wherein the plurality of service discovery protocol proxy servers includes at least one Simple Service Discovery Protocol (SSDP) proxy server.

29. A distributed data processing system comprising:

providing means for selectively providing a first service discovery protocol proxy server within a plurality of service discovery protocol proxy servers access to a shared cache for it first period of time, wherein the shared cache is used by the first service discovery protocol proxy server to process requests;

preventing means for preventing all other service discovery protocol proxy servers within the plurality of service discovery protocol proxy servers from accessing the shared cache during the first period of time; and

allowing means for allowing a second service discovery protocol proxy server within the plurality of service discovery protocol proxy servers to access the shared cache after the first period of time has elapsed, wherein each of the plurality of service discovery protocol proxy servers is assigned a given period of time for accessing the shared cache.

30. The distributed data processing system of claim 29, wherein the given period of time for accessing the shared cache is equal for each of the plurality of service discovery protocol proxy servers.

31. The distributed data processing system of claim 29, wherein the shared cache includes information identifying clients serviced by the plurality of service discovery protocol proxy servers.

32. The distributed data processing system of claim 31, wherein each of the plurality of service discovery protocol proxy servers services requests for a plurality of sets of clients identified by the information and wherein each service discovery protocol proxy server within the plurality of service discovery protocol proxy servers services requests from a different set of clients.

33. The distributed data processing system of claim 29, wherein the given period of time for accessing the shared cache assigned to each of the plurality of service discovery protocol proxy servers is selected using a round-robin scheme.

34. The distributed data processing system of claim 29, further comprising:

second allowing means for allowing a service discovery protocol proxy server access to the shared cache to multicast messages to clients handled by the service discovery protocol proxy server.

35. The distributed data processing system of claim 29, wherein the plurality of service discovery protocol proxy servers are in a universal plug and play networks.

36. The distributed data processing system of claim 29, wherein the shared cache includes information identifying clients handled by the plurality of service discovery protocol proxy servers.

37. The distributed service discovery protocol proxy servicing system of claim 29, wherein the shared cache includes information identifying clients handled by the plurality of service discovery protocol proxy servers.

38. The distributed data processing system of claim 29, wherein the plurality of service discovery protocol proxy servers handle a plurality of clients and wherein each of the plurality of service discovery protocol proxy servers handles a different subset of clients within the plurality of clients.

39. The distributed data processing system of claim 29, wherein the given time period for each service discovery protocol proxy server to access the shared cache is equal in duration to the given time period for at least one other service discovery protocol proxy server to access the shared cache.

40. A computer program product in a computer readable medium, the computer program product comprising:

first instructions for selectively providing a first service discovery protocol proxy server within a plurality of service discovery protocol proxy severs access to a shared cache for a first period of time, wherein the shared cache is used by the first service discovery protocol proxy server to process requests;

second instructions for preventing all other discovery protocol proxy servers within the plurality of service discovery protocol proxy servers from accessing the shared cache during the first period of time; and

third instructions for allowing a second service discovery protocol proxy server within the plurality of service discovery protocol proxy servers to access the shared cache after the first period of time has elapsed, wherein each of the plurality of service discovery protocol proxy servers is assigned a given period of time for accessing the shared cache.