Building applications using distributed objects and mobile code

The creation of new distributed applications requires the development of new approaches for client-server interactions. These approaches need to support utilization of resources at the client's end and distribution of services over the network. In addition tools for authoring and management of the services are also required for the new applications.

The end-user needs to be able to access the same services via different type of terminals and connections ( PC, Mobile Phone (GSM), Personal Digital Assistant, TV & Set Top Box). Of course the properties of the terminals and connections restrict the capability to access the different type of services. There should also exist a clear and secure provision of methods for service payments.

The operator and service provider are interested in setting up the service utilizing a standardized platform that provides security, quality of service and support for a variety of service types. The platform needs also provide services for the management of subscriber, service provider and billing information.

The creation of new services requires the availability of authoring tools that allow the combination of different type of material into a multimedia documents. These tools need to support a variety of material sources that provide different levels of quality and different data formats. Similarly the new emerging tools need to allow easy creation of 'mobile code' segments that interface with the other pieces of information making up the document.

Integration of the distributed object technology (CORBA) and Web provides the benefits of utilizing distributed objects and at the same time allowing the use of existing resources. The new approach of 'mobile code' notably Java provides for easy integration of existing browser and distribution technology (http/Web-browsers) with the new technology (iiop/applets/mobile-code). Similar benefits are also available at the server end. These benefits include availability of standard object services, use of Interface Definition Language to define interfaces, encapsulation of services and extensibility of the systems. The enhancements provided by the integration include services where a downloaded hypertext document contains 'mobile code' that establishes new connections to a (statefull) server, e.g. a video server. One new area where both technologies are started to be applied is service and network management. The management applications or management agents can provide a web based interface to allow access from standard browsers, that can be upgraded by using 'mobile code' approach. At the same time e.g. XoJIDM has produced mappings that translate standard definitions (SNMP or GDMO) to IDL based object interfaces. The integration of Distributed Objects/Web will also require the existence of iiop to http gateways and service traders/locators. This will provide for an easy migration and co-existence of the old web technology and new distributed object based solutions.

A standard based integration of CORBA and Web will allow the existence of information networks that combine internet and enterprise wide information sources that support new type of services.