Adaptive compression

• US 8,516,156 B1
• Filed: 07/16/2010
• Issued: 08/20/2013
• Est. Priority Date: 08/05/2005
• Status: Expired due to Fees

• Current Assignee: F5 Networks, Inc. (F5 Incorporated)
• Original Assignee: F5 Networks, Inc. (F5 Incorporated)
• Inventors: Rothstein, Jesse A., Schmitt, David D., Mukerji, Arindum
• Primary Examiner(s): RECEK, JASON D
• Application Number:
  US12/838,280
• Time in Patent Office: 1,131 Days
• Field of Search: 709/203, 709/230, 709246-247
• US Class Current: 709/247
• CPC Class Codes: H03M 7/00 Conversion of a code where information is represented by a given sequence or number of digits to a code where the same , similar or subset of information is represented by a different sequence or number of digits
• CPC Class Codes: H03M 7/30 Compression speech analysis-synthesis for redundancy reduction G10L19/00; for image communication H04N; Expansion; Suppression of unnecessary data, e.g. redundancy reduction
• CPC Class Codes: H03M 7/3068 Precoding preceding compression, e.g. Burrows-Wheeler transformation
• CPC Class Codes: H03M 7/4043 Adaptive prefix coding
• CPC Class Codes: H03M 7/6064 Selection of Compressor
• CPC Class Codes: H04L 67/06 specially adapted for file transfer, e.g. file transfer protocol [FTP]
• CPC Class Codes: H04L 69/04 Protocols for data compression, e.g. ROHC

Abstract

A method, system, and apparatus are directed towards compression of content over a network. The content may include content length information, such as within a header. In one embodiment, a portion of the content may be compressed to approximately fill a buffer of a predefined size. If there remains additional uncompressed content, a new content length may be determined based in part on the length of the compressed content and the remaining uncompressed content. The buffered content and the new content length may then be forwarded in response to the request. The remaining uncompressed content may be split into predefined blocks using identity compression. Identity compression may then be applied to the remaining uncompressed content which is then forwarded to a destination in response to the request.

Claims

1. A non-transitory computer-readable storage medium having computer-executable instructions for use in communicating a file between a client and a server over a network, the computer-executable instructions comprising program code for performing actions comprising:

receiving a file having a file length and a header having a file length number representing the file length;

compressing at least a portion of the file using a first compression mode;

determining an expected file length based, in part, on a second compression mode, wherein the expected file length is less than the received file length number and is based on another portion of the file that is currently uncompressed using the second compression mode, the second and first compression modes being different;

sending the expected file length towards the client;

after sending the expected file length toward the client, compressing at least some of the other portion of the file using the second compression mode; and

sending the compressed portions of the file towards the client.

2. The non-transitory computer-readable storage medium of claim 1, wherein the expected file length is included in a packet header.

3. The non-transitory computer-readable storage medium of claim 1, wherein at least one of the compression modes employs a gzip compression mechanism.

4. The non-transitory computer-readable storage medium of claim 1, the actions further comprising, compressing at least another portion of the file using a third compression mode.

5. The non-transitory computer-readable storage medium of claim 1, the actions further comprising, prior to sending the expected file length, compressing at least another portion of the file using another compression mode, the other compression mode having a higher level of compression than at least the first compression mode.

6. The non-transitory computer-readable storage medium of claim 1, wherein compressing at least the portion of the file further comprises employing a buffer of a fixed-size.

7. An apparatus for managing a communication, comprising:

a processor executing program code that;

compresses at least a portion of a file into a buffer using a first compression mode;

determines a file length such that when the file incompletely compresses into the buffer to determine an expected file length based on a remaining portion of the file that incompletely compresses into the buffer and prior to the remaining portion being compressed using a different compression mode, wherein determining the expected file length is based on a size of previously compressed portions, a size of remaining uncompressed portions, and at least one of a block header or size of a compression trailer; and

a transceiver to receive the file over a network, and to send the expected file length and compressed portions of the file over the network.

8. The apparatus of claim 7, wherein determining the file length further determines the expected file length at least partly based on a use of an identity compression of a second portion of the file.

9. The apparatus of claim 7, the processor executing program code that further comprises a remaining portion of the file.

10. The apparatus of claim 7, wherein the buffer is a fixed-size buffer.

11. The apparatus of claim 7, wherein determining the file length selectively uses one or more different compression modes to compress the remaining portion of the file.

12. The apparatus of claim 7, wherein the transceiver receives the file from a first network device and sends the compressed portions of the file to a different second network device.

13. The apparatus of claim 7, wherein the first compression mode employs a maximum compression.

14. An apparatus for managing a communication between a client device and a server device, comprising:

a processor having instructions that perform actions, including;

compressing portions of a file by employing at least two different compression modes and determining an expected content length based on at least one of the compression modes and prior to completing the compression of the file, wherein determining the expected file length is based on a size of previously compressed portions, a size of remaining uncompressed portions, and at least one of a block header or size of a compression trailer; and

a transceiver to receive the file over the network and to send the compressed portions of the file and to further send the expected content length over the network.

15. The apparatus of claim 14, wherein one of the at least two compression modes is an identity compression mode.

16. The apparatus of claim 14, wherein at least one of the two compression modes uses a fixed-size buffer.

17. The apparatus of claim 14, wherein first compression mode employed to compress at least a first portion of the file employs a maximum compression.

18. The apparatus of claim 14, wherein sending the compressed portions of the file and the expected content length further comprises using HTTP to send the compressed portions.