Method and system for enhancing MS exchange (MAPI) end user experiences in a split proxy environment

• US 8,505,038 B2
• Filed: 01/28/2008
• Issued: 08/06/2013
• Est. Priority Date: 01/28/2008
• Status: Expired due to Fees

• Current Assignee: CA, Inc. (d/b/a CA Technologies) (Broadcom, Inc.)
• Original Assignee: Blue Coat Systems Incorporated (Gen Digital Inc.)
• Inventors: Lakshmanan, Meenakshi Sundaram, Gailis, Janis, Lizon, Marcin, Rogobete, Adrian, Thurston, Matthew Paul
• Primary Examiner(s): DAO, TUAN C.
• Application Number:
  US12/020,954
• Publication Number:
  US 20090193443A1
• Time in Patent Office: 2,017 Days
• Field of Search: None
• US Class Current: 719/330
• CPC Class Codes: G06F 9/544 Buffers; Shared memory; Pipes
• CPC Class Codes: G06F 9/547 Remote procedure calls [RPC]; Web services

Abstract

A split proxy is configured for managing asynchronous MAPI communications between a client and a server by establishing a queuing structure for MAPI messages that make up the communications. The MAPI messages are subsequently exchanged between the client and the server using the queuing structure. Multiple remote procedure calls (RPCs) underlying the MAPI messages may be grouped together in batches for exchange between proxies of the split proxy. Also, when the client logs off from the server, a MAPI keep-alive process allows updates received at the server to be pre-populated to the split proxy for transfer to the client when it reestablishes a connection.

Claims

1. A method, comprising:

creating, at each proxy of a split proxy pair which employs byte caching at each of the proxies, message queues for messages exchanged between each of the proxies in support of messaging application programming interface (MAPI) communications between a client and a server;

setting sockets associated with each queue to listen for asynchronous communications between the client and the server;

while the client is logged off from the server, fabricating, at one or more of the proxies that comprise the split proxy, one or more MAPI messages to the server to provoke responses from the server, wherein the one or more MAPI messages resemble messages which would otherwise be sent by the client if the client were logged on; and

receiving, at a first one of the message queues at a first one of the proxies of the split proxy pair, a message associated with a remote procedure call (RPC) from the client to the server and processing the message associated with the RPC according to whether or not the first message queue is empty.

2. The method of claim 1, wherein if the first message queue is empty, then processing the message associated with the RPC immediately and transmitting a corresponding message from the first proxy to a second one of the proxies of the split proxy pair.

3. The method of claim 2, further comprising receiving, at the first proxy and from the second proxy, a message responsive to the message corresponding to the message associated with the RPC, and, upon confirming said correspondence, transmitting a message response to the message associated with the RPC from the first proxy to the client.

4. The method of claim 1, wherein if the first message queue is not empty, then determining if the message associated with the RPC has an existing response stored at the first proxy and, if so, transmitting the response from the first proxy to the client.

5. The method of claim 1, wherein if the first message queue is not empty, then determining if the message associated with the RPC has an existing response stored at the first proxy and, if not, adding the message associated with the RPC to the first message queue and transmitting a corresponding message from the first proxy to a second one of the proxies of the split proxy pair.

6. The method of claim 1, further comprising, receiving, at a second one of the message queues at a second one of the proxies of the split proxy pair, a message associated with a remote procedure call (RPC) from the client to the server and processing the message according to whether or not an identifier in the message corresponds to an identifier of a previously stored message maintained by the second proxy.

7. The method of claim 6, wherein if the identifier in the message corresponds to the identifier of the previously stored message maintained by the first proxy, then transmitting an RPC response corresponding to the previously stored message to the client.

8. The method of claim 6, wherein if the identifier in the message does not correspond to any identifiers of previously stored messages maintained by the first proxy, then processing the message associated with the RPC immediately and transmitting a corresponding message from the first proxy to the second one of the proxies of the split proxy pair.

9. The method of claim 1, wherein if the first queue is not empty, then queuing the message associated with the RPC at the first proxy.

10. The method of claim 1, wherein if the first queue is empty, then either queuing the message associated with the RPC at the first proxy or transmitting a corresponding RPC request to the server from the first proxy, depending on whether or not another RPC request is identified as being outstanding.

11. The method of claim 1, wherein if the first queue is empty, and an RPC request is presently outstanding from the first proxy, then either queuing the message associated with the RPC at the first proxy or transmitting a corresponding RPC request to the server from the first proxy depending on a status of a context parameter of the message associated with the RPC.

12. The method of claim 1, wherein if the first queue is empty, queuing the message associated with the RPC at the first proxy.

13. The method of claim 1, wherein if the first queue is not empty, and a corresponding RPC request was earlier received at the first proxy, then transferring an RPC response corresponding to the message associated with the RPC from the first proxy to the server.

14. The method of claim 1, wherein if the first queue is not empty, but no corresponding RPC request was earlier received at the first proxy, then queuing the message associated with the RPC at the first proxy.

15. A method, comprising:

configuring a split proxy, which employs byte caching at each proxy of the split proxy, for managing messaging application programming interface (MAPI) communications between a client and a server by establishing a queuing structure for MAPI messages that make up said communications;

processing said MAPI messages exchanged between the client and the server using said queuing structure, wherein queues comprising said queuing structure are set to listen for messages arriving from clients and servers asynchronously; and

while the client is logged off from the server, fabricating, at the split proxy, one or more MAPI messages to the server to provoke responses from the server, wherein the one or more MAPI messages resemble messages which would otherwise be sent by the client if the client were logged on; and

receiving, at a first one of the queues at a first one of the proxies of the split proxy, a message associated with a remote procedure call (RPC) from the client to the server and processing the message associated with the RPC according to whether or not the first queue is empty.

16. The method of claim 15, wherein multiple remote procedure calls (RPCs) underlying said MAPI messages are grouped together for batch exchange between proxies of the split proxy.

17. The method of claim 15, further comprising recognizing an event signaling the client logging off of the server and maintaining a MAPI connection between the split proxy and the server.

18. The method of claim 15, further comprising exchanging over said MAPI connection between the split proxy and the server messages intended for the client and received at the server while the client is logged off from the server.

19. The method of claim 18, wherein exchanging comprises transferring from the server to the split proxy only those of the messages intended for the client that were received at the server since a last most recent transfer of messages from the server to the split proxy.

20. The method of claim 15, wherein the queuing structure is established on a per-client basis within a context of a session associated with the client on the split proxy.

21. The method of claim 15, wherein the MAPI messages are processed on a per-client basis within a context of a session associated with the client on the split proxy.

22. A method, comprising:

establishing a user session at a split proxy, which employs byte caching at each proxy of the split proxy, the user session associated with messaging application programming interface (MAPI) communications between a client and a server;

processing MAPI messages exchanged between the client and the server asynchronously within the session;

while the client is logged off from the server, fabricating, at the split proxy, one or more MAPI messages to the server to provoke responses from the server, wherein the one or more MAPI messages resemble messages which would otherwise be sent by the client if the client were logged on; and

continuing the user session following the client logging off of the server by retrieving messages intended for the client from the server and storing the messages at a proxy of the split proxy.

23. The method of claim 22, further comprising delivering the messages to the client from the proxy.

24. A proxy, comprising a processor and non-transitory computer-readable medium storing instructions for executing by said processor, said instructions, when executed by said processor, causing said proxy to be configured to:

create message queues for exchanging messages with a corresponding proxy of a split proxy pair in support of messaging application programming interface (MAPI) communications, said messages making use of a byte cache maintained by said proxy;

set sockets associated with each queue to listen for asynchronous communications; and

fabricate one or more MAPI messages that resemble messages which would otherwise be sent by a client if the client were logged on to provoke responses to said one or more MAPI messages; and

receive, at a first one of the message queues, a message associated with a remote procedure call (RPC) from the client and process the message associated with the RPC according to whether or not the first message queue is empty.

25. The proxy of claim 24, wherein if the first message queue is empty, said instructions, when executed by said processor, cause said proxy to be configured to:

process the message associated with the RPC immediately, and then transmit a corresponding message from the corresponding proxy.

26. The proxy of claim 25, wherein said instructions, when executed by said processor, cause said proxy to be configured to:

receive a message responsive to the message corresponding to the message associated with the RPC, and, upon confirming said correspondence, transmit a message response to the message associated with the RPC.

27. The proxy of claim 24, wherein, if the first message queue is not empty, said instructions, when executed by said processor, cause said proxy to be configured to determine if the message associated with the RPC has an existing response stored at said proxy and, if so, transmit the response.

28. The proxy of claim 24, wherein, if the first message queue is not empty, said instructions, when executed by said processor, cause said proxy to be configured to determine if the message associated with the RPC has an existing response stored at said proxy and, if not, add the message associated with the RPC to the first message queue and transmit a corresponding message to the corresponding proxy.

29. The proxy of claim 24, wherein said instructions, when executed by said processor, cause said proxy to be configured to:

receive, at the first one of the message queues, a message associated with a remote procedure call (RPC) and process the message according to whether or not an identifier in the message corresponds to an identifier of a previously stored message.

30. The proxy of claim 29, wherein said instructions, when executed by said processor, cause said proxy to be configured to:

transmit an RPC response corresponding to the previously stored message if the identifier in the message corresponds to the identifier of the previously stored message.

31. The proxy of claim 29, wherein said instructions, when executed by said processor, cause said proxy to be configured to process the message associated with the RPC immediately and transmit a corresponding message to the corresponding proxy, if the identifier in the message does not correspond to any identifiers of previously stored messages.

32. The proxy of claim 24, wherein, if the first queue is not empty, said instructions, when executed by said processor, cause said proxy to be configured to queue the message associated with the RPC.

34. The proxy of claim 24, wherein if the first queue is empty, and an RPC request is presently outstanding from said proxy, then said instructions, when executed by said processor, cause said proxy to be configured to either queue the message associated with the RPC or transmit a corresponding RPC request depending on a status of a context parameter of the message associated with the RPC.

35. The proxy of claim 24, wherein if the first queue is empty, then said instructions, when executed by said processor, cause said proxy to be configured to queue the message associated with the RPC at said proxy.

36. The proxy of claim 24, wherein if the first queue is not empty, and a corresponding RPC request was earlier received, then said instructions, when executed by said processor, cause said proxy to be configured to transfer an RPC response corresponding to the message associated with the RPC.

37. The proxy of claim 24, wherein if the first queue is not empty, but no corresponding RPC request was earlier received, then said instructions, when executed by said processor, cause said proxy to be configured to queue the message associated with the RPC.

33. The method of proxy 24, wherein if the first queue is empty, then said instructions, when executed by said processor, cause said proxy to be configured to either queue the message associated with the RPC or transmit a corresponding RPC request, depending on whether or not another RPC request is identified as being outstanding.