Goal:

• Demonstrate an architecture for Automatic Configuration of Component-Based Distributed Systems.

Automatic Configuration Model:

• Prerequisites - list of software (and hardware) requirements for the execution of a particular component.
• The system is responsible for retrieving/installing all prerequisites before running the component.
• Code distribution - software components are distributed using the following schemes.
• push initiated by a system/application administrator
• pull based on component prerequisites
• mobile agents
• Dynamic Dependence Management - reifies runtime inter-component dependence. Supports:
• on-the-fly reconfiguration of running components
• proper garbage-collection
• proper exception handling

Experimentation:

• Synthetic benchmarks: evaluation of time and space overheads of automatic reconfiguration. Analyze the "Quality of Service of the reconfiguration process".
• Reflector-based Multimedia Distribution System.
• Add a CORBA interface for management. Use dynamicTAO engine for management of dynamic linking, versions, garbage collection, etc.
• Specify prerequisites
• Enable dynamic binding of new Communication protocols supporting some of the following:
• Encryption
• Authentication
• QoS
• New session protocols like RTSP, HTTP, simpleSP, etc.
• Experiment with push and pull (not agents) code distribution mechanisms.
• Clients may load network-centric video decoders on demand (software H.263, hardware/software MPEG). Reflectors may download connection handling code based on client requests, etc.
• Note that multimedia data transmission is still done through protocols based on system V sockets. CORBA is just used for management. dynamicTAO is used for (un)loading these protocols dynamically. (Justify this in the prelim statement).

1 Already Done:

• Design and implementation of DCP (Distributed Configuration Protocol). It's the basis for code distribution.
• Dynamic loading/execution of software components on top of the ORB.
• Initial model for representing runtime inter-component dependence.
• Design and implementation of a Component-based Reflector (no CORBA interface).
• Refine model for inter-component dependence. Implement prototype.

2 To be done by December 98:

• Specify high-level model for representing prerequisites. The details will be left for after the prelim. I'll probably use a very simple language. A more careful approach to this topic will be carried out by Dao (Klara's student) in the context of QoS requirement specification languages.
• Specify IDL interfaces for 2K Configuration Service.
• Interfaces for code distribution (look at Manuel's DynamicConfigurator)
• Interfaces for dependence management. (write ComponentConfigurator IDL)
• Simple description of the experiments that will be carried out later.
• Application Scenarios:
  • dynamicTAO
  • Explain how these models will be used to implement network-centrism in 2K.
  • Domain Decomposition (not part of thesis experiments)

3 To be done after the prelim:

• Implement 2K Configuration Service including code distribution and dependence management.
• Implement CORBA-interface for code management on the Reflector
• Adapt the reflector to use the 2K Configuration Service.
• Experiment with dynamic configuration of the reflector code.
• Evaluate the cost of reconfiguration with synthetic benchmarks.