This project presents a framework for runtime service discovery that supports both proactive and reactive modes. In pull mode, queries are executed when a replacement service is needed. In push mode, queries are subscribed to and executed proactively in parallel with the application to identify potential replacement services. The framework allows complex queries over service descriptions to find structurally, behaviorally, and contextually matching services. It aims to address limitations of prior approaches and maintain up-to-date candidate replacement services for use if needed.

1. Proactive and Reactive Runtime Service Discovery: A
Framework and Its Evaluation
Statement of the Project
In this project, we present a framework to support runtime service discovery. This framework
can execute service discovery queries in pull and push mode. In pull mode, it executes queries
when a need for finding a replacement service arises. In push mode, queries are subscribed to the
framework to be executed proactively and, in parallel with the operation of the application, to
identify adequate services that could be used if the need for replacing a service arises.
Why the particular topic chosen ?
SERVICE-BASED applications are composed of loosely coupled autonomous computer-based
entities owned by third parties known as services. These services are combined to realize
applications and create dynamic business processes. Due to rapid changes in market conditions
and regulations, the dynamic creation of business alliances and partnerships, and the need to
assist with changing user demands, it is necessary to provide ways of identifying services that
can fulfill specific functional and quality characteristics of service-based applications. The
identification of such services is known in the literature as service discovery and has been an
important topic of research over the last few years.
Objective and scope of the project
To address the limitations of existing approaches, we present a service discovery framework that
supports runtime service discovery based on complex queries that

2. can express flexible combinations of structural, behavioral, quality, and contextual conditions.
These queries are specified in an XML-based query language, called SerDiQueL. The framework
assumes services that have multifaceted descriptions including service interface, behavior,
quality, and context descriptions. Our framework allows service discovery based on both reactive
(pull) and proactive (push) query execution modes. In push mode, query execution is performed
in parallel to the execution of the application using presubscribed queries. These queries are
associated with specific services in an application and aim to maintain up-to-date sets of
candidate replacement services for these services. In both modes, query execution is based on
matching and the computation of distances between query and service specifications
Software Requirement Specification
Functional Requirements
 The identification of services during the execution of service-based applications to
replace services in them that are no longer available and/or fail to satisfy certain
requirement
 Pull mode operation: it should execute queries when a need for finding a replacement
service arises
 Push mode operation: here the queries are subscribed to the framework to be executed
proactively and, in parallel with the operation of the application, to identify adequate
services that could be used if the need for replacing a service arises
Non Functional Requirements
 Accessibility of this product should be user friendly so that the one who operates this tool
will not find any difficulties using this.
 Response of this product should be always fast for all the possible use cases.
 Initial setup and configuration of this tool should be very easy.
 Maintainability cost should be minimum.

3. Hardware Requirements
 Processor: Intel Pentium 4
 RAM: 512MB
 Hard disk: 40GB
Software Requirements
 Java 1.6
 J2EE 3.0
 HTML, XML, CSS, JS, JSP, JQuery
 Eclipse, Apache Tomcat, JBoss
 MySQL
Methodology Implementations

4. To address the limitations of existing approaches, we present a service discovery framework that
supports runtime service discovery based on complex queries that
can express flexible combinations of structural, behavioral, quality, and contextual conditions.
These queries are specified in an XML-based query language, called SerDiQueL. The framework
assumes services that have multifaceted descriptions including service interface, behavior,
quality, and context descriptions. Our framework allows service discovery based on both reactive
(pull) and proactive (push) query execution modes. In push mode, query execution is performed
in parallel to the execution of the application using presubscribed queries. These queries are
associated with specific services in an application and aim to maintain up-to-date sets of
candidate replacement services for these services. In both modes, query execution is based on
matching and the computation of distances between query and service specifications