Web accelerator
Encyclopedia
A web accelerator is a proxy server
that reduces web site access time
s. They can be a self-contained hardware appliance or installable software.
Web accelerators may be installed on the client (browsing) computer / mobile device, on ISP servers, on the server computer/network, or a combination. Accelerating delivery through compression requires some type of host based server to collect, compress and then deliver content to a client computer.
and other connections from which users may not be getting the best speed. Many users can achieve a 2- to 10-times speed increase in average browsing experience, while some report a 5- to 20-times speed increases for specific web sites and pages. Many ISPs offer web accelerators as a part of their dial up and broadband services. Web accelerators are typically designed for web browsing and, sometimes, for e-mailing and can not improve speeds of streaming
, gaming, P2P downloads or many other Internet applications. However, there is substantial work being done on client-side Web Accelerators for Application Delivery Networks by several companies including Cisco Systems and F5 Networks as the demand for SaaS and PaaS look set to grow among SMEs.
.
These type of server side accelerators has the added benefit of off-loading transactions and connection managements from the web or applications servers and hence, reducing its CPU utilisation and increasing web server or application scalability to handle more users with less bandwidth.
and captures the input and output from the server and a client portion sits in front of the end-users Web Browser
to capture the input and output from the browser.
Proxy server
In computer networks, a proxy server is a server that acts as an intermediary for requests from clients seeking resources from other servers. A client connects to the proxy server, requesting some service, such as a file, connection, web page, or other resource available from a different server...
that reduces web site access time
Access time
Access time is the time delay or latency between a request to an electronic system, and the access being completed or the requested data returned....
s. They can be a self-contained hardware appliance or installable software.
Web accelerators may be installed on the client (browsing) computer / mobile device, on ISP servers, on the server computer/network, or a combination. Accelerating delivery through compression requires some type of host based server to collect, compress and then deliver content to a client computer.
Techniques
Web accelerators may use several techniques to achieve this reduction:- They may cacheWeb cacheA web cache is a mechanism for the temporary storage of web documents, such as HTML pages and images, to reduce bandwidth usage, server load, and perceived lag...
recently or frequently accessed documentsElectronic documentAn electronic document is any electronic media content that are intended to be used in either an electronic form or as printed output....
so they may be sent to the clientClient (computing)A client is an application or system that accesses a service made available by a server. The server is often on another computer system, in which case the client accesses the service by way of a network....
with less latencyLagLag is a common word meaning to fail to keep up or to fall behind. In real-time applications, the term is used when the application fails to respond in a timely fashion to inputs...
or at a faster transfer rate than the remote serverServer (computing)In the context of client-server architecture, a server is a computer program running to serve the requests of other programs, the "clients". Thus, the "server" performs some computational task on behalf of "clients"...
could. - They may freshen objects in the cache ensuring that frequently accessed content is readily available for display.
- They may preemptively resolve hostnamesDomain name systemThe Domain Name System is a hierarchical distributed naming system for computers, services, or any resource connected to the Internet or a private network. It associates various information with domain names assigned to each of the participating entities...
present in a document (HTMLHTMLHyperText Markup Language is the predominant markup language for web pages. HTML elements are the basic building-blocks of webpages....
or JavascriptJavaScriptJavaScript is a prototype-based scripting language that is dynamic, weakly typed and has first-class functions. It is a multi-paradigm language, supporting object-oriented, imperative, and functional programming styles....
) in order to reduce latency. - They may prefetchLink prefetchingLink prefetching is a proprietary syntax to give web browsers a hint about documents that it should pre-fetch because the user might visit them in the near future. It is proposed as a draft internet standard by Mozilla...
documents that are likely to be accessed in the near future. - They may compressData compressionIn computer science and information theory, data compression, source coding or bit-rate reduction is the process of encoding information using fewer bits than the original representation would use....
documents to a smaller size, for example by reducing the quality of imagesDigital imageA digital image is a numeric representation of a two-dimensional image. Depending on whether or not the image resolution is fixed, it may be of vector or raster type...
or by sending only what's changed since the document was last requested. - They may optimizeOptimization (computer science)In computer science, program optimization or software optimization is the process of modifying a software system to make some aspect of it work more efficiently or use fewer resources...
the code from certain documents (such as HTMLHTMLHyperText Markup Language is the predominant markup language for web pages. HTML elements are the basic building-blocks of webpages....
or JavascriptJavaScriptJavaScript is a prototype-based scripting language that is dynamic, weakly typed and has first-class functions. It is a multi-paradigm language, supporting object-oriented, imperative, and functional programming styles....
). - They may filterFilter (software)A filter is a computer program to process a data stream. Some operating systems such as Unix are rich with filter programs. Even Windows has some simple filters built into its command shell, most of which have significant enhancements relative to the similar filter commands that were available in...
out ads and other undesirable objects so they are not sent to the client at all. - They may maintain persistent TCPTransmission Control ProtocolThe Transmission Control Protocol is one of the core protocols of the Internet Protocol Suite. TCP is one of the two original components of the suite, complementing the Internet Protocol , and therefore the entire suite is commonly referred to as TCP/IP...
connections between the client and the proxy server. - They may improve the performance via protocol level accelerations, such as TCP accelerationTCP AccelerationTCP acceleration is the name of a series of techniques for achieving better throughput on an Internet connection than standard TCP achieves, without modifying the end applications...
.
Web client accelerator
As of July 2006, these applications generally serve to improve dial-up, broadbandBroadband
The term broadband refers to a telecommunications signal or device of greater bandwidth, in some sense, than another standard or usual signal or device . Different criteria for "broad" have been applied in different contexts and at different times...
and other connections from which users may not be getting the best speed. Many users can achieve a 2- to 10-times speed increase in average browsing experience, while some report a 5- to 20-times speed increases for specific web sites and pages. Many ISPs offer web accelerators as a part of their dial up and broadband services. Web accelerators are typically designed for web browsing and, sometimes, for e-mailing and can not improve speeds of streaming
Streaming media
Streaming media is multimedia that is constantly received by and presented to an end-user while being delivered by a streaming provider.The term "presented" is used in this article in a general sense that includes audio or video playback. The name refers to the delivery method of the medium rather...
, gaming, P2P downloads or many other Internet applications. However, there is substantial work being done on client-side Web Accelerators for Application Delivery Networks by several companies including Cisco Systems and F5 Networks as the demand for SaaS and PaaS look set to grow among SMEs.
Comparison
| Web client accelerator | Compression | Operating system |
Browser | Caching | Prefetching | Optimize code |
Preemptive hostname resolution |
Ad removal | Client | Connection | Price |
|---|---|---|---|---|---|---|---|---|---|---|---|
| CACHEbox | None | Appliance (Linux) | All | Yes | Yes | No | No | Yes | End user, ISP | Broadband, Satellite, Wireless, Fiber, DSL | Commercial |
| CProxy | Gzip, images | Windows | All | ? | ? | ? | ? | ? | user | up to 756kbps | Free demo, full version 35USD per year |
| Fasterfox Fasterfox Fasterfox is a Mozilla Firefox extension that provides an interface to tweak some performance related settings such as browser network connection, cache, timings, as well as provide an optional controversial feature which forces Link prefetching. These changes can decrease page loading time... |
None | Windows, Mac, Linux and Mobile devices | Firefox | Yes | Yes | No | No | No | user | Dialup, Wireless, Broadband, DSL | Free |
| fasTun | Images, text & any gzippable data | Any | Any | No | No | HTML CSS |
Yes | Yes | All | Any | Free |
| Freewire | Images and email attachments | Windows, except NT and 95 | Internet Explorer 5.0 or higher | ? | ? | No | No | No | ISP | Dial-up | local rate |
| Google Web Accelerator Google Web Accelerator Google Web Accelerator was a web accelerator produced by Google. It used client software installed on the user's computer, as well as data caching on Google's servers, to speed up page load times by means of data compression, prefetching of content, and sharing cached data between users... (discontinued) |
Yes | Windows | Explorer, Firefox | Yes | Yes | No | No | No | user/Google server | Broadband | Free |
| Heigh Speed Heigh Speed Heigh Speed is a Web accelerator for Microsoft Windows operating systems. It works by changing settings in the Windows Registry that affect the way the operating system interacts with the network.... |
None | Windows | Any | Yes | No | No | No | No | All | Any | Commercial |
| Netfury | Images, Text, Email, HTTP downloads | Windows, Mac | Explorer, Firefox, Opera, Netscape | Yes | No | No | No | No | End User, ISP | Dial-up, Broadband, DSL, ISDN, Satellite, Wireless | £24.99 |
| Nitro | Images, Text, Email, HTTP downloads | Windows, Mac | Explorer, Firefox, Opera, Netscape | Yes | Yes | No | No | No | End User, ISP | Dial-up, Broadband, DSL, ISDN, Satellite, Wireless | $29.95 a year |
| ONSPEED OnSpeed ONSPEED is a software program designed to accelerate an internet connection using compression techniques.... |
Text & Images & Flash & Office Docs | Windows, Mac and Mobile devices | Any | No | No | No | No | No | user | Dialup, Wireless, Broadband, DSL | $49.99 (US) £24.99 pa Free (for users of BT Yahoo! Dialup Internet in the UK) |
| Polipo Polipo Polipo is a fast and lightweight, forwarding and caching proxy server and computer software daemon.By virtue of being a compliant HTTP 1.1 proxy, Polipo has all the uses of traditional Web proxies. It features HTTP 1.1, IPv4 & IPv6, traffic filtering and privacy-enhancement. Polipo supports HTTP... |
None | Unix (Linux, *BSD, Mac OS X, others), Windows | Any | Yes | No | No | No | Yes | user/ISP | Any | Free |
| Propel | Images, Text, Email, PDF, HTTP downloads | Windows, Mac | Explorer, Firefox, Opera, Netscape | Yes | No | No | No | No | End User, ISP | Dial, DSL, ISDN, Satellite, wireless | $44.95 US per year. Free with many ISP subscriptions |
| Proxyconn Web Accelerator | Text & Images & Flash & Office Docs | Windows, Mac, Mobile devices | Any | Yes | Yes | No | No | No | user | Dialup, Wireless, Broadband, DSL | $47.88 Yearly or $5.95 Monthly |
| RabbIT | Images, text & any gzippable data | Any system with Java 1.6 VM available | Any | Yes | No | No | No | Yes | ISP | Any | Free |
| Squid | None | Unix (Linux, *BSD, Mac OS X, others), Windows | Any | Yes | No | No | No | No | user/ISP | Any | Free |
| Toonel | Text & Images | Windows, Linux, Mac OS, Symbian, WindowsMobile | Any | No | No | No | No | No | user/ISP | Any | Free |
| WinGate Wingate -Places:In New Zealand:* Wingate, New Zealand, A suburb of Lower HuttIn the United Kingdom:* Wingate, County Durham* Old Wingate, County Durham* Wingates, Bolton, Greater ManchesterIn the United States:* Wingate, Indiana... |
Relies on origin | Windows (2000 onwards) | Any | Yes | No | No | No | No | All | Any | Commercial |
| Ziproxy Ziproxy Ziproxy is a forwarding, non-caching, HTTP proxy targeted for traffic optimization.The ziproxy software is regarded as lightweight in terms of memory and processing power consumption.... |
Images, text & any gzippable data | Unix (Linux, *BSD, Mac OS X, others) | Any | No | No | HTML Javascript CSS |
Yes | Yes | ISP | Any | Free |
Web server accelerator
Other web accelerators are targeted at the web site or web application owners. This type of web accelerator is installed in front of web servers and application servers and use a variety of the above techniques to improve performance to all users accessing the accelerated web sites or web applications. Sometimes referred to as a Reverse proxyReverse proxy
In computer networks, a reverse proxy is a type of proxy server that retrieves resources on behalf of a client from one or more servers. These resources are then returned to the client as though it originated from the reverse proxy itself...
.
These type of server side accelerators has the added benefit of off-loading transactions and connection managements from the web or applications servers and hence, reducing its CPU utilisation and increasing web server or application scalability to handle more users with less bandwidth.
Comparison
| Web server accelerator | Compression | Operating system |
Browser | Caching | Edge Side Includes | Prefetching | Optimize code |
Preemptive hostname resolution |
Ad removal | Client | Connection | Price |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| aiCache AiCache aiCache is an HTTP accelerator and load balancer designed to allow dynamic web pages to scale content by intelligently caching frequently requested content... |
Gzip | Linux | All | Yes | No | Yes | Yes | Yes | ? | All | High Speed | Commercial |
| CACHEbox | None | Appliance (Linux) | All | Yes | No | Yes | No | No | Yes | End user, ISP | Broadband, Satellite, Wireless, Fiber, DSL | Commercial |
| LotServer | None | Linux, Windows | All | No | No | No | No | No | No | Content Provider | Any | Commercial |
| Polipo Polipo Polipo is a fast and lightweight, forwarding and caching proxy server and computer software daemon.By virtue of being a compliant HTTP 1.1 proxy, Polipo has all the uses of traditional Web proxies. It features HTTP 1.1, IPv4 & IPv6, traffic filtering and privacy-enhancement. Polipo supports HTTP... |
None | Unix (Linux, *BSD, Mac OS X, others), Windows | Any | Yes | No | No | No | No | No | user/ISP | Any | Free |
| SiteCelerate | Text & Images | ? | Any | Yes | No | Yes | No | No | No | user/ISP | Any | Per CPU |
| Squid | None | Unix (Linux, *BSD, Mac OS X, others), Windows | Any | Yes | Yes | No | No | No | No | user/ISP | Any | Free |
| Varnish | Gzip on-the-fly compression and decompression | Unix (Linux, *BSD, Mac OS X, Solaris, others) | Any | Yes | Yes (including stitching together compressed ESI Edge Side Includes Edge Side Includes or ESI is a small markup language for edge level dynamic web content assembly. The purpose of ESI is to tackle the problem of web infrastructure scaling. It is an application of edge computing.... fragments) |
No | No | No | If You want. | All | Any | Free. Commercial support and services are available. |
| Ziproxy Ziproxy Ziproxy is a forwarding, non-caching, HTTP proxy targeted for traffic optimization.The ziproxy software is regarded as lightweight in terms of memory and processing power consumption.... |
Images, text & any gzippable data | Unix (Linux, *BSD, Mac OS X, others) | Any | No | No | No | HTML Javascript CSS |
Yes | Yes | ISP | Any | Free |
Client–server
There may be two sections to the proxy as well - a server portion sits in front of the Web serverWeb server
Web server can refer to either the hardware or the software that helps to deliver content that can be accessed through the Internet....
and captures the input and output from the server and a client portion sits in front of the end-users Web Browser
Web browser
A web browser is a software application for retrieving, presenting, and traversing information resources on the World Wide Web. An information resource is identified by a Uniform Resource Identifier and may be a web page, image, video, or other piece of content...
to capture the input and output from the browser.