The approach taken builds on the earlier work on the ANSA distributed interactive multimedia infrastructure which was released to ANSA sponsors in December 1995. This distributed processing environment (DPE) acts as the framework for developments in current and future projects. Figure 2.1 illustrates the projects in this area and how they are related to one another.
Figure 2.1: The projects and their dependencies
The Amber project proved that the adaptor and stream concepts are indeed workable. It produced an adaptor for the Internet's MBone, including a buffer class for RTP, protocol modules for IP multicast, a binder and ORB interfaces based on Sun's InterORB engine. The adaptor is placed "under" the ANSA DPE. Stubs and InterORB interfacing was handcrafted due to a lack of automated tools to do this job. AMBER demonstrates a live video multicast within the ANSA DPE.
Adherance to standards is important and the Jet project was started to provide a CORBA API over the previously released ANSA/ODP API. JET also provides a CORBA IDL compiler. Special attention is paid to ensure that all resource management is built in such a way that future multimedia support, explicit binding, streams and QoS support are assured. For this reason it was not possible to simply adapt an existing CORBA implementation. JET provides you with the ability to port simple CORBA applications onto the ANSA DPE.
The Amethyst project is to roll out the adaptor and stream concepts. This includes implementation of improved resource separation and management in the ANSA DPE. It will allow you to produce your own adaptors using the results from Jetstream. QoS management within the adaptors will also be supported as will explcit binding at the application level.
Jetstream aims to extend the tools provided in JET so that access to the added functionality provided in AMETHYST can be exploited. JETSTREAM allows programmers to write sophisticated applications which use specific functions offered through adaptors. Adaptor templates can be generated automatically. Extensions of CORBA IDL and API will be properly implemented and experience gained brought back to OMG standards activities.
JET, AMETHYST and JETSTREAM thus roll out the adaptor concept and provide the tools required to write advanced distributed applications.
Beyond the above projects we see the need to pilot real time reactive programming techniques in support of synchronous programming. The Ruby project will create an exploratory pilot implementation.