Adaptive network traffic compression mechanism including dynamic selection of compression algorithms

• US 7,420,992 B1
• Filed: 03/17/2005
• Issued: 09/02/2008
• Est. Priority Date: 03/17/2005
• Status: Active Grant

• Current Assignee: CA, Inc. (d/b/a CA Technologies) (Broadcom, Inc.)
• Original Assignee: Packeteer Incorporated (Gen Digital Inc.)
• Inventors: Fang, Li, Laier, Mary Louise
• Primary Examiner(s): Ngo; Ricky
• Assistant Examiner(s): SINKANTARAKORN, PAWARIS
• Application Number:
  US11/082,638
• Time in Patent Office: 1,265 Days
• Field of Search: 370/464, 370/465, 370/466, 370/474, 370/476, 370/477, 370/521, 375/240, 341/51, 709/247
• US Class Current: 370/477
• CPC Class Codes: H04L 1/0002 by adapting the transmission rate
• CPC Class Codes: H04L 1/187 Details of sliding window management
• CPC Class Codes: H04L 12/4633 Interconnection of networks using encapsulation techniques, e.g. tunneling

Abstract

An adaptive compression mechanism that dynamically selects compression algorithms applied to network application traffic to improve performance. One implementation includes an arbitration scheme that reduces the impact on computing resources required to analyze different compression algorithms for different network applications. The adaptive compression functionality of the present invention can be integrated into network application traffic management or acceleration systems.

Claims

1. A data compression device, comprising

at least one network interface;

a network traffic compression module comprising a plurality of compression algorithm sub-modules each implementing a compression algorithm, wherein the network traffic compression module is operably coupled to the at least one network interface, and operative, in an active compression mode, to

establish compression tunnels with a remote network device in the communications path to one or more destination hosts;

intercept outgoing data packets to the one or more destination hosts;

compress the outgoing data packets using a first compression algorithm;

maintain compression statistics characterizing the operation of the first compression algorithm;

and, wherein the network traffic compression module is further operative, in a passive compression mode, to

copy the outgoing data packets;

compress the copied outgoing data packets using a second compression algorithm;

maintain compression statistics characterizing the operation of the second compression algorithm;

discard the packets resulting from the second compression algorithm; and

wherein data compression device is operative to

compare the compression statistics associated with the first and second compression algorithms;

select a compression algorithm for the active compression mode based on a comparison of the compression statistics; and

select a new compression algorithm for the passive compression mode after the comparison of the compression statistics.

2. The apparatus of claim 1 wherein the compression statistics comprise compression ratios.

3. The data compression device of claim 1 further comprising

a tunnel probing module operative to

dynamically probe a communications path to a destination host for at least one network device having compression capabilities;

and

establish a compression tunnel with an identified network device in the communications path.

4. The apparatus of claim 3 wherein the tunnel probing module is operative to

transmit probe requests along the communications path to the destination host;

and

receive probe responses from network devices in the communications path to the destination host.

5. A data compression device, comprising

at least one network interface;

a network traffic compression module comprising a plurality of compression algorithm sub-modules each implementing a compression algorithm, wherein the network traffic compression module is operably coupled to the at least one network interface, and operative, in an active compression mode, to

establish compression tunnels with a remote network device in the communications path to one or more destination hosts;

intercept outgoing data packets to the one or more destination hosts;

compress the outgoing data packets using a first compression algorithm;

maintain compression statistics characterizing the operation of the first compression algorithm;

and, wherein the network traffic compression module is further operative, in a passive compression mode, to

copy the outgoing data packets;

compress the copied outgoing data packets using a second compression algorithm;

maintain compression statistics characterizing the operation of the second compression algorithm;

discard the packets resulting from the second compression algorithm; and

wherein data compression device is operative to

compare, on a periodic basis, the compression statistics associated with the first and second compression algorithms;

select a compression algorithm from the active and passive compression algorithms for the active compression mode based on a comparison of the compression statistics; and

select a new compression algorithm for the passive compression mode after the comparison of the compression statistics.

6. An adaptive data compression device, comprising

at least one network interface;

a network traffic identification module operative to match data flows to a network application from a plurality of network applications;

a network application data structure containing at least one identifier corresponding to one of the plurality of network applications in association with an active compression algorithm and a passive compression algorithm;

a network traffic compression module comprising a plurality of compression algorithm sub-modules each implementing a compression algorithm, wherein the network traffic compression module is operably coupled to the at least one network interface, and operative, in an active compression mode, to

establish compression tunnels with a remote network device in the communications path to one or more destination hosts;

intercept outgoing data packets to the one or more destination hosts;

compress the outgoing data packets of a data flow using a first compression algorithm, wherein the first algorithm is selected based on the active compression algorithm identified in the network application data structure corresponding to the network application matched to the data flow;

maintain a compression ratio characterizing the operation of the first compression algorithm;

and, wherein the network traffic compression module is further operative, in a passive compression mode, to

copy the outgoing data packets;

compress the copied outgoing data packets using a second compression algorithm, wherein the second algorithm is selected based on the passive compression algorithm identified in the network application data structure corresponding to the network application matched to the data flow;

maintain a compression ratio characterizing the operation of the second compression algorithm;

discard the packets resulting from the second compression algorithm; and

wherein data compression device is operative to compare the compression ratios associated with the first and second compression algorithms.

7. The data compression device of claim 6 wherein the data compression device is further operative to select a compression algorithm for the active compression mode based on a comparison of the compression ratios.

8. The data compression device of claim 7 wherein the data compression device is further operative to select a new compression algorithm for the passive compression mode after the comparison of the compression ratios.

9. The data compression device of claim 6 wherein the data compression device is further operative, on a periodic basis, to select a compression algorithm from the active and passive compression algorithms for the active compression mode based on a comparison of the compression ratios.

10. The data compression device of claim 9 wherein the data compression device is further operative to select a new compression algorithm for the passive compression mode after the comparison of the compression ratios.