computer science crazy|
Joined: Dec 2008
23-10-2009, 04:00 PM
Caching popular objects close to the users provides an opportunity to combat this latency by allowing users to fetch data from a nearby cache rather than from a distant server. Web caching has been recognized as one of the effective schemes to alleviate the service bottleneck and reduce the network traffic, thereby minimize the user access latency
Use Search at http://topicideas.net/search.php wisely To Get Information About Project Topic and Seminar ideas with report/source code along pdf and ppt presenaion
Active In SP
Joined: Feb 2012
03-03-2012, 02:33 PM
WEB CACHE.doc (Size: 53.5 KB / Downloads: 33)
. Introduction to Web caching
The introduction of World Wide Web has changed the view of the user community to the network in respect to accessibility and user friendliness. With the Web the user is able to look for and retrieve all kind of information from the network without having any knowledge of the network. From the user point of view it does not matter if the information he is looking for, e.g. a video clip with sound effects is on a computer in the next room or on the other side of the world. This leads to an enormous growth of traffic on the local, national and international network backbone. Because the use of the Web is growing exponentially it is to be expected that the WWW traffic on the national and international networks also will grow exponential with raising latency. Nevertheless the user expects a high quality of service with modest response times.
2. What's a Web Cache?
A web cache sits between Web servers and a client or many clients, and watches requests for HTML pages, images and files (collectively known as objects) come by, saving a copy for itself. Then, if there is another request for the same object, it will use the copy that it has, instead of asking the origin server for it again.
Because the request is satisfied from the cache (which is closer to the client) instead of the origin server.
3. Use of Web Caches.
There are two main reasons that Web caches are used:
• To reduce latency - Because the request is satisfied from the cache (which is closer to the client) instead of the origin server, it takes less time for the client to get the object and display it. This makes Web sites seem more responsive.
• To reduce traffic - Because each object is only gotten from the server once, it reduces the amount of bandwidth used by a client. This saves money if the client is paying by traffic, and keeps their bandwidth requirements lower and more manageable.
4. Kinds of Web Caches
4.1. Browser Caches
A section of computer's hard disk to store objects that you've seen. The browser cache works according to fairly simple rules. It will check to make sure that the objects are fresh, usually once a session (that is, the once in the current invocation of the browser).