25-08-2017, 09:32 PM
multiple parameter for web service
LITERATURE Report_Multiple parameter for web services.docx (Size: 299.17 KB / Downloads: 31)
INTRODUCTION
Objective:
As the web is increasingly used not only to find answers to specific information needs but also to carry out various tasks, enhancing the capabilities of current web search engines with effective and efficient techniques for web service retrieval and selection becomes an important issue. Existing service matchmakers typically determine the relevance between a web service advertisement and a service request by computing an overall score that aggregates individual matching scores among the various parameters in their descriptions.
Web services are software entities that have a well defined interface and perform a specific task. Typical examples include services returning information to the user, such as news or weather forecast services, or services altering the world state, such as online shopping or booking services. A web service is formally described in a standardized language (WSDL). The service description may include the names and types of input and output parameters, preconditions and effects, as well as Quality of Service (QoS) attributes, such as price, execution time, availability, and reputation. As web services and service providers proliferate, there will be a large number of candidate, and likely competing, services for fulfilling a desired task. Hence, effective service discovery mechanisms are required for identifying and retrieving the most appropriate services. Assume the existence of a repository that contains a large number of advertised service descriptions. In a typical scenario, a user provides a complete definition of the requested service, and issues a discovery query.
EXISTING SYSTEM
To handle the inherent ambiguity in dominance relationships among advertised services, our methodology adapts the notion of uncertain dominance from. Briefly, a service dominates another with a probability that depends on multiple criteria PDMs. Then, advertisements are ranked or clustered with respect to their uncertain dominance relationships. The main contributions of our work are summarized as follows:
1. It is implement a method for determining dominance relationships among service advertisements that simultaneously takes into consideration multiple PDM criteria.
2. Ranking web services based on dominance relationships and discuss efficient algorithms.
3. Clustering web services based on dominance relationships and discusses efficient algorithms.
4. It is extensively evaluate our approaches in terms of retrieval effectiveness, using real requests and relevance sets, and in terms of efficiency, using synthetic scenarios.
Service Dominance Scores
This section introduces the notion of web service dominance and discusses related concepts used in the following for service ranking and clustering. We model a web service operation as a function that receives a number of inputs and returns a number of outputs. Other parameters, such as preconditions, effects, QoS, can be incorporated seamlessly. Assume a service request Q with a set of input Pin and output Pout parameters. We write Qj to denote the jth input parameter, where Pj 2 Pin. Further, let S be an advertised service with input and output parameters Pin and Pout, respectively. Note that S can be a match to Q, even when their parameter sets’ cardinalities differ, e.g., an advertisement that produces more outputs than requested
Clustering Web Services
Clustering organizes advertisements so that services within a cluster provide similar matches with respect to the request. Since several parameters are involved in the matchmaking process, finding a service that provides a high degree of match for all parameters is difficult; instead, it is often needed to decide between different trade-offs. Clustering the search results allows the user to identify an interesting advertisement and then browse similar results, i.e., those found within the same cluster.
LITERATURE SURVEY
Introduction:
Web services are software entities that have a well-defined interface and perform a specific task. Typical examples include services returning information to the user, such as news or weather forecast services, or services altering the world state, such as online shopping or booking services. A web service is formally described in a standardized language (WSDL). The service description may include the names and types of input and output parameters, preconditions and effects, as well as Quality of Service (QoS) attributes, such as price, execution time, availability, and reputation.