WO2002029585A1

WO2002029585A1 - Image transfer system and method

Info

Publication number: WO2002029585A1
Application number: PCT/US2001/041953
Authority: WO
Inventors: Israel L'heureux; Christopher Peiffer
Original assignee: Redline Networks, Inc.
Priority date: 2000-10-06
Filing date: 2001-08-31
Publication date: 2002-04-11
Also published as: AU2001289176A1

Abstract

An image transfer system and method. The method typically includes receiving a request (104) for original data from a remote client. The request (104) is received at a network device (28) positioned on a computer netowrk (16) intermediate the remote client and the web server. The method further includes at the network device, obtaining original image data from the web server. The method further includes, creating a smaller version of the image data from the original image data, sending the smaller version of the image data to the remote client, and sending the original image data to the remote client.

Description

IMAGE TRANSFER SYSTEM AND METHOD

Technical Field

The present invention relates generally to data transmission on computer

networks, and more particularly to acceleration of transmission of a web resource over

a computer network.

Background of the Invention

The Internet has experienced explosive growth in recent years. The

emergence of the World Wide Web has enabled millions of users around the world to

download easily web pages containing text, graphics, video, and sound data while at

home, work, or from remote locations via wireless devices. These web pages often are

large in size and therefore require a long time to download, causing the user delay and

frustration. Delay often causes users to abandon the requested web page and move on

to another web page, resulting in lost revenue and exposure for many commercial web

sites.

Delay downloading a web page can be caused by a number of factors.

At the server, a large volume of page requests may overload the capacity of the server

and result in unanswered or late-answered requests. Within the computer network,

network congestion and limited bandwidth may cause delay in the transmission of

data. Particularly problematic is the so-called "last mile" between many home users

and their Internet Service Provider. For a majority of Internet users, the last mile is

typically a telephone modem connection configured to operate at speeds at or lower

than 56K baud. For these users, large web pages take an agonizingly long time to

download. It would be desirable to provide a system and method for accelerating

data transmission over a computer network, in order to decrease delay and provide

users with a more pleasurable experience.

Summary of the Invention

An image transfer system and method are provided. The method

typically includes receiving a request for original image data from a remote client. The

request is received at a networking device positioned on a computer network

intermediate the remote client and a web server. The method further includes at the

networking device, obtaining original image data from the web server. The method

further includes, creating a smaller version of the image data from the original image

data, sending the smaller version of the image data to the remote client, and sending

the original image data to the remote client.

Brief Description of the Drawings

Fig. 1 is a schematic view of a network data acceleration system

according to one embodiment of the present invention.

Fig. 2 is a schematic view of a network data acceleration system

according to another embodiment of the present invention.

Fig. 3 is a schematic view of a network data acceleration device

according to one embodiment of the present invention.

Fig. 4 is a schematic view of a network data acceleration device

according to another embodiment of the present invention.

Fig. 5 is a schematic view of a network data acceleration device

according to yet another embodiment of the present invention. Fig. 6 is a flowchart of a method for computer networking according to

one embodiment of the present invention.

Fig. 7 is a flowchart of a method for computer networking according to

another embodiment of the present invention.

Fig. 8 is a continuation of the flowchart of Fig. 7.

Fig. 9 is a flowchart of one embodiment of a method for accomplishing

the step of filtering web page source data, shown in Fig. 7.

Fig. 10 is a flowchart of one embodiment of a method for accomplishing

the step of creating a smaller version of the image data, shown in Fig. 8.

Fig. 11 is a continuation of the flowchart of Fig. 10.

Fig. 12 is a flowchart of a method for transferring image data over a

computer network, according to one embodiment of the present invention.

Fig. 13 is a flowchart of a method for transferring web page source data

over a computer network, according to one embodiment of the present invention.

Fig. 14 is a schematic view of a data flow according to one embodiment

of the present invention.

Fig. 15 is a web page according to one embodiment of the present

invention, shown with a smaller version of the image data.

Fig. 16 is the web page of Fig. 15, shown with an original, unmodified

version of the image data of Fig. 15.

Fig. 17 is a listing of original web page source data. Fig. 18 is a listing of filtered web page source data including a hyperlink

to a smaller version of an inline image, filtered according to one embodiment of the

present invention.

Fig. 19 is a listing of the filtered web page source data of Fig. 18,

rewritten to include a hyperlink to an original version of the inline image.

Detailed Description of the Invention

Referring initially to Fig. 1, a computer networking system according to

one embodiment of the present invention is shown generally at 10. System 10

typically includes a plurality of remote clients 12 configured to download data from

servers 14 via computer network 16. Remote clients 12 are typically computing

devices, such as personal computers (PCs), portable data assistants (PDAs), web-

enabled wireless telephones, mainframe computers, etc.

System 10 further includes an acceleration device 18 positioned

intermediate each of remote clients 12 and servers 14. Acceleration device 18 is

configured to accelerate the transmission of data between the server 14 and remote

client 12. Acceleration device 18 is alternatively referred to herein as networking

device 18.

Typically, acceleration devices 18 are stand-alone appliances linked to

computer network 16. According to an alternative embodiment of the invention,

system 10 may include an acceleration device 18' integrated into server 14'.

Acceleration devices 18 may be connected to servers 14 in a one-to-one relationship,

or in a one-to-many relationship, as shown. When one acceleration device 18 is linked

to several servers 14, it functions to distribute requests from remote clients 12 to the many servers 14, thereby approximately balancing the load placed on each of the

servers.

Typically, acceleration devices 18 are connected to servers 14 via Local

Area Networks (LANs) 20, and are connected to remote clients 12 via computer

network 16, which is typically a Wide Area Network 16, such as the Internet. Remote

clients 12 may be connected to WAN 16 directly via a broadband connection 24, or

via an Internet Service Provider (ISP) 22. Typically, remote client 12 and ISP 22 are

linked via a modem connection through the Public Switched Telephone Network

(PSTN) 26. A typical operating speed for the PSTN modem connection 26 is

approximately 56K bits per second (bps) or less, while a typical operating speed for

direct broadband connection 24 is between about 256K bps to 10 Megabits per

second, and may be higher.

A remote server 28 may be provided to serve additional data to remote

clients 12 via computer network 16. This data is referred to herein as remotely served

content, and in the case where web server 14 and remote server 28 are operated by

different content providers, may be referred to herein as third-party content. Remotely

served content is shown in Figs. 15 and 16 at 42. Typically, remote server 28 is an

advertising server 28 configured to serve an advertisement to remote client 12. In

addition to advertising, it will be appreciated that the remotely served content may be

virtually any other type of information, such as news, weather, stock quotes, etc., and

may contain graphics, text, images, video, and/or sounds. The function of remote

server 28 will be further described below. Servers 14, 28 typically are web servers 14, 28 configured to serve a

web resource, shown at 30 in Fig. 14, to browser programs 34 executed on remote

clients 12. Exemplary browser programs 34 include the Netscape browser

commercially available from Netscape Communications Corporation of Santa Clara,

California and the Internet Explorer browser commercially available from Microsoft

Corporation of Redmond, Washington. The web servers and browsers typically

communicate using the HyperText Transfer Protocol (HTTP). The web resource may

be web page source data 32, image data 33, sound data, video data, graphics data,

embedded code such as a JavaScript applet, a stylesheet, or virtually any other

resource accessible and interpretable by a browser via a Uniform Resource Indicator

(URI).

In Fig. 2, another embodiment of a computer networking system

according to the present invention is shown at 10'. Computer networking system 10'

typically includes server-side acceleration devices 18a positioned in the same location

as described above for acceleration devices 18 of Fig. 1: Computer networking system

10' also typically includes remote client-side acceleration devices 18b positioned

intermediate computer network 16 and a respective remote client 12. Typically,

acceleration devices 18b are positioned at a dial-up ISP 22a, or at a broadband ISP

22b.

In the embodiment depicted in Fig. 2, acceleration devices 18a and 18b

function in the manner described below, and also have the additional ability to

communicate with each other using a binary protocol, thereby avoiding use of

standard ASCII protocols such as HTTP, and decreasing the number of bits required for transmission of the web resource. In addition, acceleration devices 18a and 18b

have the ability to establish an Internet Protocol (IP) level connection, and

communicate in the binary protocol without using Transmission Control Protocol

(TCP). TCP includes handshaking and other procedures that require valuable time and

slow down the overall data transmission rate. Therefore, avoiding use of TCP

effectively increases the rate at which data is transferred. Finally, the acceleration

devices 18a and 18b have the ability to establish persistent connections with each

other. Persistent connections are network connections on sockets that are always kept

open once they are established. By keeping a connection open, the acceleration

devices avoid repeating tasks associated with the opening and closing of sockets,

thereby saving valuable time and increasing the overall data transmission rate.

Turning to Fig. 14, web resource 30 typically includes web page source

data 32 and associated image data 33. Web resource 30 may also include other types

of files such as video files, sound files, graphic animation files, embedded code files

such as JavaScript applets, cascading stylesheets (CSS), etc. Web page source data 32

typically is encoded using a markup language such as the HyperText Markup

Language (HTML), while image data 34 typically is encoded in a standard image

format such as the JPEG, GIF, or animated GIF image formats. It will be appreciated

that other suitable file formats may be used for the web page source data and the

image data.

Web page source data 32 includes renderable data 36 and non-

renderable data 38. Renderable data 36 is data that browser 34 is configured to

interpret when rendering a web page 40 using web resource 30. That is, renderable data 36 is data that affects the manner in which browser 34 presents the visual and

aural content and layout of web page 40, as well as the interactive functions of web

page 40. Renderable data 36 includes, but is not limited to, text, images, layout and

formatting instructions, background color, hyperlinks, graphic animations, sounds, etc.

Non-renderable data 38 is data that is not interpreted by browser 34 in a

manner that affects the visual or aural content or layout of web page 40, nor the

interactive function of web page 40. For example, whitespace, hard returns,

comments, meta tags, keywords, etc. are examples of non-renderable data. Non-

renderable data 38 also includes formatting instructions, such as HTML tags, which

browser 34 on remote client 12 is not configured to interpret. Image data 33 may also

contain non-renderable data such as author, title, comments, and creation date data.

As will be discussed in detail below, acceleration device 18 typically is

configured to accelerate transmission of web resource 30 from server 14 to remote

client 12 by processing web resource 30 to form a modified, size-optimized version of

the web resource 30a. Size-optimized version 30a is smaller in file size than original

web resource 30, and therefore takes less time to transfer via computer network 16.

Where web resource 30 includes web page source data 32, size-

optimized version 30a of the original web resource 30 typically includes filtered web

page source data 32a, produced by filtering at least a portion of non-renderable data

38 from original web page source data 32. Where web resource 30 includes image

data 33, the size-optimized version 30a of the original data may include a smaller

version of the image data 33 a, produced by altering an image parameter of the image

data and/or modifying the format of the image data, as described below. Turning now to Figs. 15 and 16, a web page rendered by browser 34

based on web resource 30 is shown at 40. Web page 40 typically includes remotely

served content 42, served by remote server 28, as well as heading 44, inline image 46,

and text 48. The text and formatting of web page 40 are determined by formatting

instructions, also referred to as tags, and text data contained within web page source

data 32. It will be understood that the ultimate visual and aural presentation of the web

page 40 typically is not altered by filtering all or a portion of non-renderable data 38

from web page source data 32 by acceleration device 18.

Web page source data 32 contains a hyperlink, shown at 36g in Fig. 17,

to remote server 28 for remotely served content 42. Hyperlink 36g typically includes a

uniform resource locator (URL), and instructs browser 34 to request the image data

for the remotely served content from remote server 28. Web page source data 32 also

contains a hyperlink, shown at 36i in Fig. 17 and at 36k in Fig. 18, to inline image 46.

Hyperlink 36i instructs browser 34 to request image data 33 corresponding to inline

image 46 from web server 14.

As will be described below, according to one embodiment of the present

invention, upon request by the browser for the image data, the acceleration device is

configured to send a smaller version of the image data 33 a, which is presented as size-

optimized inline image 46a. After size-optimized inline image 46a is displayed, the

web server typically instructs browser 34 to request an original, unmodified version of

image data 33. The original version of image data 33 is ultimately displayed as

original, unmodified inline image 46 via browser 34. Typically, the web server

instructs the browser to download the original version of image data 33 by embedding a script (typically JavaScript) or other executable code in web page source data 32 for

web page 40. This script is configured to rewrite the web page in the browser

memory, such that the link 36k that was used to point to the smaller version of the

image data 33 a, is replaced with a link 36m that points to an original version of the

image data 33.

To access web page 40, a user of remote client 12 typically establishes a

connection to computer network 16 via ISP 22, and enters a Uniform Resource

Locator (URL) of a desired web page 40 served by web server 14 into browser 34.

Browser 34 typically sends a request to the web server 14 to serve the desired web

page. Typically, acceleration device 18 is located at the IP address contained within

the URL for the web server. Acceleration device 18 is configured to receive and

process the request sent to web server 14, to accelerate the transmission of web

resource 30 from web server 14 to remote client 12, as described below.

As shown in Fig. 3, acceleration device 18 includes a controller 50

having a memory 52 and central processing unit (CPU) 54 linked by a bus 56.

Acceleration device 18 also typically includes a mass storage device 58 having a

communications program 60 and cache 62. Communications program 60 is configured

to process requests for web resource 30 from remote clients 12 according to the

methods shown in Figs. 6-13 and described below. Cache 62 is configured to store

web resources 30, such as web page source data 32, filtered web page source data 32a

and image data 33, 33a, previously requested by remote clients 12.

Acceleration device 18 also typically includes a network interface 64

coupled to bus 56 and to an external network connection to computer network 16. Network interface 64 is configured to enable acceleration device 18 to send and

receive data via computer network 16. An example of a suitable network interface is

the Intel Ethernet Pro 100 network card, commercially available from Intel

Corporation of Hillsboro, Oregon. Acceleration device 18 also may include a digital

signal processor (DSP) 66 configured to create a smaller version 33a of image data 33

in real-time, according to the methods described below in detail in Figs. 10-12.

Examples of commercially available DSPs suitable for use as DSP 66 are the Texas

Instruments 6501/6503 digital signal processors, commercially available from Texas

Instruments, Inc., of Dallas, Texas.

In Fig. 4, another embodiment of an acceleration device according to the

present invention is shown generally at 18". Acceleration device 18" typically

includes a single integrated circuit board 68. The integrated circuit board contains a

bus 70 connecting a network interface 72, memory 74, CPU 76, Application Specific

Integrated Circuit (ASIC) 78, and mass storage device 80. ASIC 78 typically contains

the communication program 60, while mass storage device 80 typically contains the

cache 62, described above. It will be appreciated that the embodiments of the

acceleration device 18, 18" may be a stand-alone network appliance 18 or may be

integrated with a web server 14', as shown at 18' in Fig. 1. ASIC 78, CPU 76, and

memory 74 form a controller 82 configured to process requests for web resources

according to the methods described below.

In Fig. 6, yet another embodiment of an acceleration device according to

the present invention is shown generally at 18'". Acceleration device 18'" typically

includes a plurality of co-processing CPUs 84, 86 linked to each other and to RAM 88, non-volatile memory 90, and network interface 92 by a bus 94. Components 84-94

are typically mounted to a circuit board 96. Non-volatile memory is typically solid

state memory such as flash memory or ROM, and contains communication program

60, described above. Ram 88 is available to CPUs 84, 86 for temporary storage of data

when the CPUs are processing web requests according to the methods described

below. Acceleration device 18'" typically does not include a mass storage device or

cache, although alternatively a mass storage device and cache may be included.

Components 84, 86, 88, and 90 form a controller configured to process requests for

web resources according to the methods described below.

Turning now to Fig. 6, a method according to one embodiment of the

present invention is shown generally at 100. Method 100 typically includes, at 102,

listening at acceleration device 102 for a request for web resource 30. At 104, the

method typically includes receiving a request for web resource 30 from remote client

browser 12. Typically, the request is sent from remote client browser 12 to the IP

address that the remote client browser associates with a web server 14, but which is

actually assigned to an associated acceleration device 18. The request is typically

received at acceleration device 18.

The method further includes at 106, obtaining original web resource

corresponding to the requested web resource from web server 14. Typically, the

original web resource is obtained by acceleration device 18. Alternatively,

acceleration device 18 may determine that the requested web resource is cached, and

may obtain the requested web resource from cache 62. At 108, the method typically includes processing, at acceleration device

18, at least a portion of original web resource 30 to form size-optimized web resource

30a having a smaller file size than original web resource 30. Typically web resource

30 is processed based on its file type, according to the steps shown in Figs. 7-8.

At 110, the method further includes, sending size-optimized web

resource 30a to remote client 12. Typically size-optimized web resource 30a is sent

from acceleration device 18 via computer network 16 to requesting remote client 12.

The size-optimized web page is received by remote client 12 and is displayed on a

display 12a associated with remote client 12.

At 112, the method further includes sending at least the portion of

original web resource 30 that was size-optimized to the remote client in an original,

unmodified state. Thus, method 100 may include sending from acceleration device 18

to remote client 12 all of original web resource 30 in an original unmodified state, or

may include sending only a portion of original web_' resource 30 in an original

unmodified state. According to one embodiment of the invention, web resource 30

may include web page source data 32 and image data 33, and the method at 112 may

include sending only original image data 33 in an original, unmodified state.

Turning now to Figs. 7 and 8, method 100 of Fig. 6 is shown in greater

detail. Method 100 typically includes listening at 102, receiving a request for web

resource 30 at 104, and obtaining requested web resource 30 at 106, as described

above. At 105, the method includes determining a hardware configuration of the

remote client. The hardware configuration is typically the number of colors supported

by display 12a, as well as the resolution of display 12a. The hardware configuration is typically detected by sending an embedded file in web page source data, the file being

configured to instruct the browser to send the hardware configuration to the web

server in subsequent communications. The hardware configuration may be used to

determine an optimum image data format for image data sent to remote client 12, as

described below.

The step of processing web resource 30 is shown in detail at 108 in Fig.

7-11. Processing web resource 108 typically includes, at 114, determining a remote

client browser type and/or browser-interpretable file type. Typically, the remote client

browser is either the Netscape browser, or the Internet Explorer browser, discussed

above, or a browser compatible with one of these two browsers. Of course, it will be

appreciated that other browser types may also be detected. The remote client browser

type will be used to determine a compression algorithm for compressing data at steps

124 and 128. Browser-interpretable file types are typically sent in a request header

from the remote client 12, and may include file types such as GZIP, DEFLATE,

WAVELET compression and other file formats.

Processing web resource 108 also typically includes, at 116, determining

a content type of web resource 30. Typically, the web resource is either web page

source data 32, such as an HTML file, or image data 33. The method typically

determines the content type of the web resource by examining the file extension, such

as .html, .jpg, .gif, etc.

At 118, if the content type of web resource 30 shows that web resource

30 is image data 33, then method 100 proceeds to step 132 of Fig 8. At 120, if the content type of web resource 30 shows that the web resource is web page source data

32, then method 100 proceeds to step 122.

At 122, processing 108 further includes filtering web page source data

32, thereby creating modified web page source data 32a, smaller in size than original

web page source data 32. Modified web page source data 32a is also referred to herein

as filtered web page source data 32a. Typically, the method includes filtering the web

page source data 32 in real-time, after the request is received and before the filtered

web page source data is sent to remote client 12.

Typically, filtering the web page source data is accomplished by

filtering at least a portion of non-renderable data 38 from web page source data 32. In

one embodiment of the invention, all of non-renderable data 38 is filtered from the

web page source data 32. Alternatively, only a portion of the non-renderable data is

filtered from the web page source data.

Typically, the non-renderable data is filtered according to a process

shown in Fig. 9. At 146, the step of filtering 122 typically includes a substep of

filtering whitespace from the web page source data. As used herein, the term

whitespace refers to space, tab, and other characters in the web page source data 32

that will not be rendered in web page 40, shown at 38b and 38c in Fig. 17.

At 148, the step of filtering 122 typically includes a substep of filtering

comments from the web page source data 32. Comments appear in web page source

data 32 in the form shown at 38h in Fig. 17.

At 150, the step of filtering 122 typically includes a substep of filtering

hard returns, shown at 38a in Fig. 17, out of web page source data 32. In HTML, a return or paragraph tag is used to instruct browser 34 to make a hard return in a file.

However, in ASCII a return is accomplished either by a carriage return character (CR)

and/or a line feed character (LF). Typically, CR and LF ASCII characters are not

rendered by browser 34. Therefore, either or both of these characters may be filtered

out of web page source data 32. In one embodiment of the invention, the method

includes filtering out only the second of two consecutive CRLF character

combinations. Thus, where CRLF CRLF appears in the web page source data 32, the

second CRLF is filtered out and the first is left intact in the modified web page source

data 32a. Due to formatting differences between browser types, the method may also

include deleting hard returns in a manner based on browser type detected at step 114.

At 152, the step of filtering 122 typically includes a substep of filtering

meta tags, shown at 38d in Fig. 17. Meta tags 38d are tags that contain keywords 38g

used by Internet search engines to categorize and index web page 40. These meta tags

38d and the keywords 38g contained therein are not rendered by browser 34, and are

thus typically filtered out of web page source data 32. Author and other data in meta

tags 38d may also be filtered out.

At 154, the step of filtering 122 includes filtering tags by rewriting tags

in lowercase- letters. Rewriting the tags in lowercase letters tends to reduce the size of

the image data after compression by a method such as GZIP or DEFLATE. Thus,

rewriting tags in lowercase letters results in a filtered web page source data 32a with a

smaller file size than original web page source data 32.

Additionally, filtering the web page source file at 122 may include

filtering renderable data in a loss-less manner. For example, the method may include filtering a portion of the renderable data from the web page source data, and replacing

the portion of the renderable data with substitute renderable data smaller in size and

renderably equivalent to the replaced renderable data. Renderably equivalent data is

data that is interpreted by browser 34 in a visually, aurally, and interactively identical

manner. One example of substituting renderably equivalent data is substituting a set of

formatting instructions with an equivalent stylesheet. Thus, the present may include

substituting a stylesheet for a set of formatting instructions in web page source data

32.

Returning to Fig. 7, once filtered web page source data 32a is produced,

method 100 returns to step 124, at which point filtered web page source data 32a is

compressed in real-time at the acceleration device. If the detected browser type from

step 114 is Internet Explorer, filtered web page source data 32a is typically

compressed using the GZIP compression algorithm. If the detected browser type from

step 114 is Netscape, the filtered web page source data 32a is typically compressed

using the DEFLATE compression algorithm. Alternatively, the method may include

detecting whether GZIP, DELFATE, or other compression algorithm is a browser-

interpretable file type at 114.

At 126, the method further includes sending the compressed, filtered

web page source data 32a from acceleration device 18 to remote client 12 for display

via browser 34. The method may also include, either automatically or in response to a

request from the user, sending the original web page source data 32 to the remote

client browser after sending compressed, filtered web page source data 32a to the

browser. If at 120, it is determined that web resource 30 is not web page source

data 32, then method 100 typically includes compressing web resource 30 in an

original, unmodified state, in real-time, using a compression algorithm selected based

on browser type or browser-interpretable file format, as described above. At 130, the

method further includes sending compressed, original web resource 30 to remote

client 12 via computer network 16.

If at 118 it is determined that web resource 30 is image data 33, then

method 100 typically includes, at 132, determining whether a smaller version of image

data 33a is cached on cache 62. If a smaller version of the image data 33a is already

stored on cache 62, the method includes retrieving the smaller version 33a from cache

62 and, at 134, sending smaller version 33a of the image data to remote client 12 for

display via browser 34 as smaller image 46a on web page 40. Step 134 is one

exemplary way of accomplishing step 110 of Fig. 6.

At 136, the method typically includes instructing browser 34 to request

original image data 33. Typically, this is accomplished by rewriting or replacing a

hyperlink in web page source data 32. The hyperlink is shown before rewriting at 36k

in Fig. 18, and after rewriting at 36m in Fig. 19. Before rewriting, hyperlink 36k

points to the smaller version 33a of the image data, and, after rewriting, hyperlink

36m points to original image data 33. Rewriting the hyperlink prompts browser 34 to

request the original version of image data 33.

In response to this request, the method includes, at 138, sending an

original, unmodified version of image data 33 to remote client 12. Browser 34 on

remote client 12 displays the original image data as original, unmodified image 46 on web page 40a. Step 138, and step 140 described below, are two illustrative ways of

accomplishing step 112 in Fig. 6. From step 138, the method typically returns to

listening for new requests for web resources at step 102 in Fig. 7.

If at step 132, it is determined that a smaller version 33a of the image

data is not cached, then method 100 typically includes, at 140, sending original image

data 33 to browser 34 on remote client 12. Browser 34 displays original image data 33

as image 46 on the web page. Thus, the first time that acceleration device 18

encounters a request for a particular image data 33, the image is typically sent to the

requesting remote client without first sending a smaller version 33a of the image data.

This is because, according to one preferred embodiment of the invention, image

processing is not performed in real-time, in order to decrease latency in serving the

requested image data to remote client 12.

Alternatively, according to another preferred embodiment of the

invention, image data 33 may be processed in real-time by DSP 66 of acceleration

device 18. According to this embodiment of the invention, a smaller version 33a of the

image data is created in real-time and sent to remote client 12, followed shortly

thereafter by the original image data 33.

After the original image is sent at 140, the method further includes, at

142, creating a smaller version 33a of original image data 33 and, at 144, caching the

smaller version 33a on cache 62. After caching the smaller version 33a, the method

subsequently returns to listening for new requests for web resource at 102 in Fig. 7. As shown in Fig. 10, the step of creating the smaller version 33a of the

image data is typically accomplished by, at 156, determining one or more image

parameters. The image parameters may include number of colors, similarity of colors,

file size, resolution, or other image parameters. At 158, the method typically includes

selecting an optimum data format for the image data based on browser interpretable

data format(s) determined at 114, a hardware configuration of remote client 12,

determined at 105, and the image parameter(s) determined at 156. For example, if the

user's display 12a is configured to display only 256 colors, and the original image

data 33 includes millions of colors, the present method is configured to convert the

file format of the image data to a 256 color file format and send the 256 color image to

the remote client as smaller version 33 a. By way of this example, it will be understood

that the smaller version 33a of the image file may be generated by means of loss-less

compression. That is, smaller image 46a may appear identical to original image 46 to

the user of remote client 12, because the user's hardware configuration is not

configured to fully display the colors or resolution of the original image 46.

At 160, the method further includes determining if the image data is

already stored in the optimum file format. If so, the method proceeds to Fig. 11. If not,

the method further includes, at 162, modifying the format of the original image data to

he optimum data format. Thus, acceleration device 18 is configured to receive image

data in one format such as JPEG, for example, and convert the image data into another

optimum format, such as GIF, before sending the image to the requesting remote

client 12. This conversion may be performed in real time by a DSP, or may be

performed "off line" by caching an image file in the optimum format for future requests and sending the image file in an unmodified format to the current requesting

remote client 12.

As shown in Figs. 11, step 142 of creating the smaller version 33a of the

image data is typically further accomplished by, at 168, determining whether original

image data 33 is animated (such as an animated GIF file), and if so, extracting a frame

of the image data at 170. Typically, the first frame is extracted, although virtually any

suitable frame may be extracted. The first frame is then cached as smaller version 33a

of the image data. The first frame may further be reduced in size by reducing the

number of colors or reducing a quality parameter associated with the first frame, as

described below.

At 172, the method further includes determining whether original image

data 33 is in a JPEG format. If so, the method further includes, at 174, reducing a

quality parameter associated with JPEG image data 33. This reduces the overall file

size of JPEG image data 33. The resultant image data is cached as smaller version 33a

of image data 33.

At 176, the method further includes determining whether original image

data 33 is in a GIF format. If so, the method further includes, at 178, reducing the

number of colors in the GIF image data. This reduces the overall file size of GIF

image data 33. The resultant image data is cached as smaller version 33a of image

data 33.

Turning now to Fig. 12, a method for transmitting image data according

to another embodiment of the present invention is shown generally at 200. Method

200 typically includes, at 202, listening for a request from a remote client 12 for web resource 30. Listening at 202, as well as all other steps in methods 200, is typically

performed by acceleration device 18, described above. At 204, the method typically

includes receiving a request for original image data 33 from a browser 34 on remote

client 12.

At 206, the method typically includes, determining whether original

image data 33 and an associated smaller version 33a are cached on cache 62. If not,

the method proceeds to 208, where the method includes obtaining requested original

image data 33 from web server 14.

At 210, the method further includes creating a smaller version 33a of

image data 33. Typically, this is accomplished by, at 211, modifying the image data to

an optimum format, at 212, extracting a frame of animated image data, at 214,

reducing a quality parameter associated with image data, and or at 216, or reducing

the number of colors associated with the image data. These steps are described in

detail above.

At 218, the method typically includes, sending smaller version 33a of

image data 33 to browser 34 of remote client 12 for display as smaller image 46a on a

web page 40. The method may also include instructing browser 34 to request original

version of image data 33, typically by rewriting a hyperlink, as described above. At

220, the method typically includes sending original version of image data 33 to

browser 34 for display as original image 46 in web page 40a.

Alternatively, method 200 may proceed directly from obtaining the

original image from web server 14 at 208, to sending the original image to remote

client 12 at 220, thereby reducing latent processing time at acceleration device 18. In this embodiment, the method typically includes creating a smaller version 33a

according to step 218 and caching the smaller version 33a on cache 62 after an

original image 33 is sent to remote client 12 at 220. The method subsequently returns

to listening at 202.

If, at 206, it is determined that original image 33 and associated smaller

version 33a of the image previously created according to step 210, is cached, then the

method typically further includes retrieving the original and smaller versions 33, 33a

from the cache at step 222, and sending the original and smaller versions 33, 33a to

the remote client 12 at steps 218, 220. The method subsequently returns to listening at

202.

Turning now to Fig. 13, a method for transmitting web page source data

according to another embodiment of the invention is shown generally at 300. Method

300 typically includes, at 302, listening for a request for web page source data 32 from

a remote client 12. The step of listening, as well as all other steps of method 300, are

typically performed by acceleration device 18, described above.

At 304, the method typically includes receiving a request for web page

source data 32, such as an HTML file, from a browser 34 on remote client 12. At 306,

the method further includes obtaining requested web page source data 32 from an

associated web server 14. The web page source data may also be obtained from cache

62 if it is static web page source data stored thereon.

Typically, web page source data 32 includes renderable data 36 and non-

renderable data 38, as described above. At 308, the method typically includes filtering

at least a portion of non-renderable data 38 from the web page source data, thereby creating a modified and filtered version 32a of the original web page source data.

Modified web page source data 32a is smaller in file size than original web page

source data 32.

Typically, filtering at 308 is accomplished by one or more of filtering

substeps 310-316. At 310, the method may include filtering whitespace from web

page source data 32, as described above. At 312, the method may include filtering

comments from the web page source data, as described above. At 314, the method

may include filtering hard returns from the web page source data, as described above.

At 316^ the method may include filtering tags from the web page source data by

rewriting the tags in lowercase, as described above. In addition, the method may

include filtering non-renderable commands such as HTML tags that browser 34

cannot interpret.

At 318, the method typically includes sending modified and filtered web

page source data 32a to browser 34 on remote client 12. The method may also include,

before sending the modified web page source data 32a, compressing modified web

page source data 32a. The compression algorithm used to compress the modified web

page source data may be selected based on a detected browser type and/or browser-

interpretable data format, as described above.

Browser 34 is configured to display modified web page source data 32a

as web page 40. The visual and aural presentation of modified web page source data

32a via browser 34 is typically identical to the visual and aural presentation of original

web page source data 32 via browser 34. That is, the two files 32, 32a look, sound,

and interact in the same manner for a user of browser 34. Turning now to Fig. 17, an example of original web page source data is

shown generally at 32. Typically, web page source data 32 is in the HTML format,

and may be a static file or may be dynamically generated. Web page source data 32

typically includes renderable data 36 and non-renderable data 38, as described above.

Renderable data 36 typically includes HTML tags relating to language and formatting,

such as HTML tag 36a, HEAD tag 36b, TITLE tag 36c, BODY tag 36d, CENTER

tag 36e, anchor (A) tag 36f, image (IMG) tags 36g, 36i, and heading (HI) tag 36h.

Renderable data 36 also includes text data 36 , and linked image data. Image tag 36i is

a hyperlink to an original version of the image data 33.

Non-renderable data 38 typically includes hard returns 38a and

whitespace such as tabs 38b and spaces 38c. Non-renderable data further includes

meta tags 36d, which contain parameters such as the author parameter 36e, and the

content parameter 36f. The content parameter 36f typically contains keywords 36g,

which are used by search engines to catalog and index the web page. Non-renderable

data 36 further includes comments 36h. Any and or all of non-renderable data 36 may

be filtered out of web page source data 32 according to the embodiments of the

present invention.

Fig. 18 shows filtered web page source data 32a, with a hyperlink 36k to

smaller version 33a of image data 33. Whitespace, hard returns, meta tags (including

author, and content-related keywords) and comments have been removed. Browser 34

interprets web, page source data 32a to display web page 40 (having smaller image

46a) on remote client 12. Because web page source data 32a has the non-renderable

data filtered from it, and because it contains a hyperlink to a smaller image file 33 a, it requires less time to download than web page source data 32. Thus, the user may view

web page 40 more quickly using the herein described data transmission methods than

using conventional methods.

Fig. 19 shows filtered web page source data 32a', with a hyperlink 36m

to original image data 33. Typically, embedded code (typically an applet) is inserted

into the web page source data 32 to cause the browser 34 to rewrite the filtered web

page source data 32a to the form shown at 32a', as described above. Browser 34

interprets web page source data 32a' to display web page 40a on remote client 12.

Thus, while having the benefit of being able to download web page 40 quickly, the

user is eventually able to view an original version 46 of image data 33.

The above described invention may be used to accelerate data

transmission over a computer network, in order to decrease delay and provide users

with a more pleasurable experience.

While the present invention has been particularly shown and described

with reference to the foregoing preferred embodiments, those skilled in the art will

understand that many variations may be made therein without departing from the spirit

and scope of the invention as defined in the following claims. The description of the

invention should be understood to include all novel and non-obvious combinations of

elements described herein, and claims may be presented in this or a later application to

any novel and non-obvious combination of these elements. The foregoing

embodiments are illustrative, and no single feature or element is essential to all

possible combinations that may be claimed in this or a later application. Where the

claims recite "a" or "a first" element or the equivalent thereof, such claims should be understood to include incorporation of one or more such elements, neither requiring

nor excluding two or more such elements.

Claims

WE CLAIM:

1. A method for transferring image data between a web server and a

remote client over a computer network, comprising:

receiving a request for original image data from a remote client, the

request being received at a networking device positioned on a computer network

intermediate the remote client and web server;

at the networking device, obtaining original image data from the web

server;

creating a smaller version of the image data from the original image file;

sending the smaller version of the image data to the remote client; and

sending the original image file to the remote client.

2. The method of claim 1, wherein creating a smaller version of the

image data includes modifying the format of the image data.

3. The method of claim 2, wherein the format of the image data is

modified based a parameter selected from the group consisting of remote client

hardware configuration, image data size, image data number of colors, image data

similarity of colors, and browser-interpretable file formats.

4. The method of claim 1, wherein creating a smaller version of the

image data includes reducing a quality parameter in image data in JPEG format.

5. The method of claim 1, wherein creating a smaller version of the

image data includes reducing a number of colors in image data in GIF format.

6. The method of claim 1, wherein the image data is animated.

7. The method of claim 6, wherein creating a smaller version of the

animated image data includes extracting a frame.

8. The method of claim 7, wherein extracting a frame from the

animated image data includes extracting only a first frame of the animated image data.

9. The method of claim 8, whereby the extracted first frame from

the animated image data is comprised of GIF format, thereby creating a smaller

version of the first frame of the animated image file by reducing the number of colors.

10. The method of claim 1, wherein after creating the smaller version

of the image data, the smaller version of the image data is cached.

11. The method of claim 1 , further comprising, instructing the remote

client to request the original image data.

12. The method of claim 11, wherein the remote client is instructed

to request the original image file by executing code embedded in a web page, the code

being configured to rewrite a hyperlink pointing to the smaller version of the image

data to a hyperlink pointing to the original image data.

13. The method of claim 1, wherein the original image data is

configured to be displayed on the remote client in the same space as the smaller

version of the image data.