Web 2. 0 has introduced some new technologies and concepts in the web development arena. Based on the objectives of building situational, agile, efficient, variant, and low-cost web applications, the idea of Mashups has evolved. The business need to reduce the cost of building new, small-to-medium-size applications that may not be durable to the extent that justifies the high cost of building traditional web applications has emphasized the Mashups direction. Mashups focus on what is widely called "Long Tail" which represents the 80% of the applications that affect 20% of the users as opposed to the traditional enterprise applications as shown in Figure 1 below: In mashups, given a set of mashups building blocks (e. g. , widgets), a large number of situational applications may be composed with little or no coding effort to serve certain business need. It is to be noted that this paper deals with enterprise mashups (that are data-centric) rather than user mashups (that are visual-centric). An important feature in enterprise mashup is its ability to "mash up" data from different sources. These sources may include XML, HTML, Web Services, RSS, and others. Figure 2 depicts different data sources that can be mashed up together. Moreover, existing mashups can be utilized to result into new mashups that provide a completely-new mashups. This trend allows for a better agility and response time for business demands. Because the process of assembling mashups is repetitive, standardizing or formalizing this process would save much effort and time for further assembly processes and would ensure better final results as well. This paper defines a pattern structure to be followed by those contributing to standardizing the process of mashup assembly. Moreover, it provides a sample mashup design pattern that would clearly realize this concept.

Mashup Web 2. 0 Architectural Patterns Design Patterns Widgets