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WEB SERVICES:

Web Services have emerged as a new standard, where applications over the Internet communicate with each other, independent of platform language and implementation. Traditionally middleware technologies like DCOM, RMI and CORBA were used, where-in a new TCP connection is made every time an application needs to access a remote procedure, which has to cut through the firewalls. Interoperability between various technologies is a big issue.

Web Services use XML based standards like WSDL, UDDI, and SOAP to describe locate and communicate between various applications.

WSDL (Web Service Description Language):

WSDL is used to define Web services and describes how to access them. The client that needs to access the service has to know the URL of the service providers wsdl file.

UDDI (Universal Description Discovery and Integration):

UDDI is a universal repository which contains all the services. It is like a telephone book's white, yellow, and green pages. The project allows businesses to list themselves by name, product, location, or the Web services they offer.

SOAP (Simple Object Access Protocol):

It is a XML based messaging protocol that encapsulates and exchanges the RPC calls. The SOAP messages are communicated over HTTP independent of platform and language.

We have been using the following servers for our projects:

Systinet’s WASP

Apache’s Axis

Java Web Service Developer Pack

PROJECTS:

Intelligent Web Service Framework:
Developing an Intelligent Agent which would automatically access multiple web services on behalf of the client.
Team: Narasimha Raju Gottumukkala
The Intelligent Web services Framework accesses multiple web services and chooses the most appropriate service according to the users preference. Multi Attribute Utility Technique is used for the generic decision making process. The attribute values for different types of services are mapped dynamically to the decision making algorithm and the users preferences are normalized as weights. The services attribute values are stored in an offline xml repository, and updated depending on whether the data is push type, pull or static. This framework is deployed as a Web Service to enable it to access it from any platform and language. Two types of services, namely book selling web services for comparing books, and mission critical application for comparing the performance of web services are implemented to pick out the best service.

Aggregate Web Service Portal (AWSP):
Portal offering aggregate web services and using trusted third parties for security.
Team: Haritha Juturu
This system has been divided into 3 modules. First is the user module consists of the users the user interface and the client proxies. The users interact with the server delegated for the user interface. They register using the PKI mechanism using Single Sign-On for all services. This is useful because the every business application a user requests is an aggregation of smaller services. Their information is stored in the user profile files in the DataBase. The Registration entity will take care of this. For the database in module one I would like to use the LDAP database or use the portal builder Jetspeed which has its own authentication and database systems. The client proxies for the user who is requesting the web services are created at runtime. The second module consists of the repository of dervices which interacts with the web service providers and the clients. These connect to the repository which will have a web service manager and a web service publish helper. The publish helper will help the web service provider to register their service in the system. The web service manager takes care of publishing the WSDL files which will describe the interfaces for the services which have registered with the system. The third module consists of the server which has the service providers. After the session is established between the user and the system, the user can interact directly with the service provider server via SOAP over HTTP.