It is generally observed throughout the world that in the last two decades, while the average speed of computers has almost doubled in a span of around eighteen months, the average speed of the network has doubled merely in a span of just eight months! In order to improve the performance, more and more researchers are focusing their research in the field of computers and its related technologies. Internet is one such technology that plays a major role in simplifying the information sharing and retrieval. World Wide Web (WWW) is one such service provided by the Internet. It acts as a medium for sharing of information. As a result, millions of applications run on the Internet and cause increased network traffic and put a great demand on the available network infrastructure.
TopBackground
As the Internet continues to nurture in size and popularity, web traffic and network problems are the major issues in the Internet world. Sustained increase in demand for objects on the Internet causes ruthless overloads on many websites and network links. The Internet users have no patience to wait even for few seconds to download a desired webpage. Web traffic reduction techniques are necessary for accessing the websites efficiently with the existing network facility. There are many factors that affect the performances of web: variations in network connectivity distance between nodes and congestion in networks or servers. This is due to unpredicted market or service demands. Hence, web caching with web pre-fetching techniques reduce the web latency that we normally face on the Internet.
Also, WWW is an evolving system and consists of interlinked objects like audio, images, videos and so on. Here, web caching and pre-fetching is found as an important strategy to enhance performance of web-based system. Recently WWW is most widely used by many users to distribute information across the world. Therefore, it leads to increased network traffic over the Internet and web server. As a result, web becomes one of the primary areas to hold up network performance.
Transferring of web objects over the Internet increases the network traffic; thus, reducing bandwidth for competing requests and increasing latencies for web users while accessing the webpages. In order to reduce such access delay, it is desirable to store popular web objects closer to the user so that they can access them. Hence, proxy-based pre-fetching technique has been used. Thus, web caching and web pre-fetching has become an important research topic to reduce the noticeable response latency incurred by the end users (Sathiyamoorthi & Murali Bhaskaran 2010a).
Moreover, research in web caching is considered very important due to the issues and challenges exist and arise in the following dimensions (Wessels & Duane 2001):
Therefore, web caching and web pre-fetching are methods needed for the increase of web performance (Sathiyamoorthi & Murali Bhaskaran 2013).
Further improvement in the web application often is achieved through data mining techniques (Bamshad 2007). These techniques are generally known as web mining. The following sections provide an overview of some of ascertained techniques.