HTTP accelerator

A web accelerator is a proxy server that reduces web site access time. They can be a self-contained hardware appliance or installable software.

Web accelerators may be installed on the client (browsing) computer or 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.

Web accelerators may use several techniques to achieve this reduction in access time:

They may

These techniques align with best practices which are typically recommended to improve the performance of web applications.

As of July 2006, these applications generally serve to improve dial-up, broadband 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 small and medium enterprises.

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. Web server accelerators are sometimes referred to as reverse proxies or Application Delivery Controllers. This type of server side accelerator has the added benefit of off-loading transactions and connection managements from the web or applications servers and hence, reducing its CPU utilization and increasing web server or application scalability to handle more users with less bandwidth.

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