A Component Based Programming Framework for Autonomic Applications Hua Liu, Manish Parashar, and Salim Hariri ICAC ‘04 John Otto Wi06 CS 395/495 Autonomic Computing Systems

Outline Pervasive wide-area distributed computing  Management  Existing frameworks  Accord Autonomic Application Characteristics  Application Context  Component Definition  Dynamic Composition Example: Forest Fire Application Current Project State Final Thoughts

Management: Challenges Heterogeneous resources  Physical location, connectivity method  Hardware functionality  Software interface Uncertainty  Dynamism  Failures  Incomplete knowledge

Management: Requirements Separation of interface definition from implementation Separation of application computation from component interactions On-the-fly interaction programmability Self-monitoring and resource adaptation to changing application demands and system state

Outline Pervasive wide-area distributed computing  Management  Existing frameworks  Accord Autonomic Application Characteristics  Application Context  Component Definition  Dynamic Composition Example: Forest Fire Application Current Project State Final Thoughts

Component-based Frameworks Examples  CORBA – related to Interface Definition Language  CCA – Common Component Architecture  JavaBeans – Java Component Architecture Pros: separate interface from implementation Cons: no self-management of components

Service-based Frameworks Examples  Web services (e.g. XML-RPC?)  Grid service model Pros: little prior knowledge required Cons  Rigid behavior, no customization  Grid service model requires reliable accessibility

Outline Pervasive wide-area distributed computing  Management  Existing frameworks  Accord Autonomic Application Characteristics  Application Context  Component Definition  Dynamic Composition Example: Forest Fire Application Current Project State Final Thoughts

Accord Programming Framework Builds on Grid model Allows definition of  Autonomic components  Their respective behaviors  Interactions between components Uses dynamic rules, defined at run-time, to organize components

Outline Pervasive wide-area distributed computing  Management  Existing frameworks  Accord Autonomic Application Characteristics  Application Context  Component Definition  Dynamic Composition Example: Forest Fire Application Current Project State Final Thoughts

Application Context Define “common syntax and semantics”  Allows definition of rules governing component interactions Extends CCA and OGSA (Open Grid Services Architecture)  uses existing mechanisms for defining context

Outline Pervasive wide-area distributed computing  Management  Existing frameworks  Accord Autonomic Application Characteristics  Application Context  Component Definition  Dynamic Composition Example: Forest Fire Application Current Project State Final Thoughts

Component Definition Extends traditional component model  Specified interfaces  Context dependencies Allows self-managed operation based on rule set and constraints Interface defined by several ports…

Port-based Interface Functional port  Defines inputs and outputs Control port  Sensors and actuator interfaces for controlling and gaining state information about a component Operational port  Rule definition interface governing actions under specified conditions  Rule types…

Operational Port: Rule Types Behavior rules  Control computation, algorithms based on context and input events Interaction rules  Establish methods and contents of communication between components  Define interaction with environment, autonomic application as a whole

Outline Pervasive wide-area distributed computing  Management  Existing frameworks  Accord Autonomic Application Characteristics  Application Context  Component Definition  Dynamic Composition Example: Forest Fire Application Current Project State Final Thoughts

Dynamic Composition Run-time assembly of components:  “which components are composed”  “how and when they interact”

Accord: Dynamic Composition Component creation and registration with AutoMate Component replacement  New component registration  Old component deactivation (quiescent state) Allowable because connectivity is not required  State transfer  New component activation

Accord: Dynamic Composition Addition of components  New component creation  State injection based on user-defined interaction rules  State injection into related components to notify them of new component availability Deletion of components  Related components delete component from interaction rules  AutoMate cleans up after the deleted component

Accord: Dynamic Composition Creation/Modification/Deletion of interaction rules  Rule agents (autonomic elements) can create new interactions based on application context  Users can adjust rules used by autonomic elements at run-time to change application function without restarting the system

Outline Pervasive wide-area distributed computing  Management  Existing frameworks  Accord Autonomic Application Characteristics  Application Context  Component Definition  Dynamic Composition Example: Forest Fire Application Current Project State Final Thoughts

Example Components DSM (Data Space Manager) CRM (Computation Resource Manager) Rothermel (Simulates fire spread) WindModel (Simulates wind direction) GUI (Manages user interaction)

Component Interaction Rules

Behavior Rules

Outline Pervasive wide-area distributed computing  Management  Existing frameworks  Accord Autonomic Application Characteristics  Application Context  Component Definition  Dynamic Composition Example: Forest Fire Application Current Project State Final Thoughts

Requisite Performance Metrics

Outline Pervasive wide-area distributed computing  Management  Existing frameworks  Accord Autonomic Application Characteristics  Application Context  Component Definition  Dynamic Composition Example: Forest Fire Application Current Project State Final Thoughts

Questions and Thoughts Simply a component-based distributed application architecture, where some components measure system state and send control messages to other components—is this really innovative? What is the interface language, specifically? Demonstrates the necessary components for an autonomic framework, but I’m not convinced that it’s either innovative or robust.

A Component Based Programming Framework for Autonomic Applications Hua Liu, Manish Parashar, and Salim Hariri ICAC ‘04 John Otto Wi06 CS 395/495 Autonomic Computing Systems