Method and apparatus for optimizing message transmission

• US 5,870,563 A
• Filed: 10/11/1995
• Issued: 02/09/1999
• Est. Priority Date: 09/19/1992
• Status: Expired due to Fees

• Current Assignee: International Business Machines Corporation
• Original Assignee: International Business Machines Corporation
• Inventors: Roper, Michael Ian, Evans, Lawrence Steven, Wallis, Graham Derek
• Primary Examiner(s): SHAH, ALPESH
• Application Number:
  US08/540,506
• Time in Patent Office: 1,217 Days
• Field of Search: 395/800, 395/200.02, 395/200.1, 395/200.11, 395/200.13, 395/200.2, 395/831, 395/834, 395/838, 395/850, 395/500, 395/650, 395/885, 395/800.01 , 395/200.31, 395/200.6, 395/200.68, 395/200.76, 395/200.79, 395/670, 370/17, 370/82, 370/83, 370/84, 370/99, 370/105.1, 370/351, 370/389, 370/396, 370/464, 370/465, 370/469, 370/476
• US Class Current: 709/239
• CPC Class Codes: H04L 69/04 Protocols for data compression, e.g. ROHC
• CPC Class Codes: H04L 69/18 Multiprotocol handlers, e.g. single devices capable of handling multiple protocols
• CPC Class Codes: H04L 9/40 Network security protocols
• CPC Class Codes: H04Q 11/0435 Details

Abstract

Computers are linked together to form a network. Messages are sent over the links between the computers in compressed, segmented form, the size of the segments being appropriate to the transmission characteristics of the link. A message previously received or transmitted by a computer is stored in compressed and segmented form. If it is desired to forward or re-transmit this message, the segment size of the stored form is compared against the optimum segment size for the link over which the message is to be sent. If there is a close match, then the stored segmented, compressed message is retrieved for direct transmittal, without having to resegment or recompress the message.

Claims

1. In a computer network having a plurality of computers interconnected by different types of transmission links, a method for operating computers in said computer network comprising the steps of:

(a) simultaneously storing in at least one computer multiple different forms of a message,

said multiple different forms of the message including an original form, and at least one of a form suitable for transmission over the different types of transmission links to other computers in the computer network, and a form intermediate the original form and the form suitable for transmission over the different types of transmission links;

(b) determining, in the at least one computer, if the message is to be forwarded to one or more of the other computers;

(c) if the message is to be forwarded, selecting a form of the message with characteristics which are compatible with the links over which the message is to be transmitted; and

(d) transmitting the selected message over the links to the one or more other computers.

2. The method of claim 1 wherein step (b) further includes the step of deleting the message from the at least one computer if the message is not to be forwarded.

3. A method of operating a computer in a network including at least first and second other computers, including the steps of:

receiving a message at the computer from said first other computer over a link with said first other computer, said message having been processed before sending from an original form into a form suitable for transmission;

processing the message, on receipt at the computer, back into the original form;

simultaneously storing the message received by the computer in at least one of the transmitted form, and a form intermediate the original form and the transmitted form;

deciding at the computer to forward the message to said second other computer in the network;

retrieving the stored message and processing it if necessary into a form suitable for transmission; and

sending the retrieved message to said second other computer.

4. The method of claim 3 wherein processing the message from the original form into a form suitable for transmission includes compressing the message, and said step of storing comprises storing the message in compressed form.

5. The method of claim 3 wherein processing the message from the original form into a form suitable for transmission includes segmenting the message, and said step of storing comprises storing the message in segmented form.

6. The method of claim 5, further comprising the step of determining whether the stored message has a segment size appropriate for transmission over the link which the message is to be transmitted to said second other computer.

7. The method of claim 6 wherein the segment size appropriate for transmission is determined based on the time required to re-segment the message relative to the delay that would be incurred by using a non-optimum segment size.

8. The method of claim 7 further including the step of monitoring the current performance of the network in order to determine the optimum segment size for each link.

9. The method of claim 3, further comprising the step of deleting the stored message if the stored message is not to be forwarded to said second other computer.

10. The method of claim 3, further comprising the step of storing the message in original form and wherein each processed form of the message is stored in a linked chain appended to the stored original form of the message.

11. A method of operating a computer in a network including the steps of:

processing at the computer, a message from an original form into a form suitable for transmission;

transmitting said message in processed form from the computer over a link to a first other computer in the network;

storing in the computer the message in at least one of the transmitted form, and a form intermediate the original form and the transmitted form;

deciding at the computer to forward the message to a second other computer in the network;

retrieving the stored message and processing the retrieved message if necessary into a form suitable for transmission; and

sending the processed message to said second other computer.

12. The method of claim 11, wherein the step of processing the message from the original form into a form suitable for transmission includes compressing the message, and said step of storing comprises storing the message in compressed form.

13. The method of claim 12, wherein the step of processing the message from the original form into a form suitable for transmission includes segmenting the message, and said step of storing comprises storing the message in segmented form.

14. The method of claim 13, further comprising the step of determining whether the stored message has a segment size appropriate for the link over which the message is to be transmitted to said second other computer.

15. The method of claim 14, wherein the segment size is determined based on the time required to re-segment the message relative to the delay that would be incurred by using a non-optimum segment size.

16. The method of claim 15, further including the step of monitoring the current performance of the network in order to determine the optimum segment size for each link.

17. The method of claim 11, further comprising the step of deleting the stored message if it is decided not to forward the message to said second other computer.

18. The method of claim 11, further comprising the step of also storing the message in original form, and wherein each processed form of the message is stored in a linked chain appended to the stored original form of the message.

19. A computer adapted for use in a network, wherein messages are transmitted from the computer over links with at least first and second other computers in the network, said computer comprising:

means for processing a message before sending to said first other computer from an original form into a form suitable for transmission;

means for storing the message transmitted from the computer to said first other computer in either the transmitted form, or a form intermediate the original form and the transmitted form;

means for deciding to forward the message to said second other computer;

means for retrieving the stored message and processing the stored message if the stored message is not in a form suitable for transmission; and

means for sending the retrieved message or the processed message to said second other computer.

20. The computer of claim 19, including means for compressing the message in order to process the message from the original form into a form suitable for transmission, the message being stored in compressed form.

21. The computer of claim 19, including means for segmenting the message in order to process the message from the original form into a form suitable for transmission, the message being stored in segmented form.

22. The computer of claim 21 further including means for determining whether the stored message has a segment size appropriate for the link over which the message is to be transmitted.

23. The computer of claim 22 further including means for monitoring the current performance of the network in order to determine the optimum segment size for each link.

24. The computer of claim 19, further comprising means for deleting the stored message if said stored message is not to be forwarded to said second other computer.

25. A computer adapted for use in a network, wherein messages are transmitted to and from the computer over links with at least first and second other computers in the network, said computer comprising:

means for receiving a message from said first other computer, said message having been processed before sending from an original form into a form suitable for transmission;

means for processing the message on receipt back into the original form;

means for storing the message in either the transmitted form, or a form intermediate the original form and the transmitted form;

means for deciding to forward the message to said second other computer;

means for retrieving the stored message and processing it if necessary into a form suitable for transmission; and

means for sending the retrieved message to said second other computer.

26. The computer of claim 25, including means for compressing the message in order to process the message from the original form into a form suitable for transmission, the message being stored in compressed form.

27. The computer of claim 25, including means for segmenting the message in order to process the message from the original form into a form suitable for transmission, the message being stored in segmented form.

28. The computer of claim 27, further including means for determining whether the stored message has a segment size appropriate for the link over which the message is to be transmitted.

29. The computer of claim 28, further including means for monitoring the current performance of the network in order to determine the optimum segment size for each link.

30. The computer of claim 25, further comprising means for deleting the stored message if it is decided not to forward the message to said second other computer.

31. A method of transmitting data to a subset of a network of computers wherein messages are transmitted to and from a computer over links with other computers in the network, messages being processed before sending from an original form into a form suitable for transmission, and processed on receipt back into the original form, messages being stored in either a transmitted form, or a form intermediate the original form and the transmitted form and retrieved from storage for sending to another computer, said method comprising the steps of:

transmitting a first message specifying the subset of the network to which the data is to be transmitted; and

transmitting a second message containing the data, wherein a computer receiving the second message uses the information in the first message to forward the second message to another computer in the network without having to first process the second message back into its original form.