tailieunhanh - Integrated Research in GRID Computing- P3

Integrated Research in GRID Computing- P3:The deployment process for adaptive Grid applications does not finish when the application is started. Several activities have to be performed while the application is active, and actually the deployment system must rely on at least one permanent process or daemon. | Towards a common deployment model for Grid systems 25 Application Execution The deployment process for adaptive Grid applications does not finish when the application is started. Several activities have to be performed while the application is active and actually the deployment system must rely on at least one permanent process or daemon. The whole application life-cycle must be managed in order to support new resource requests for application adaptation to schedule a restart if an application failure is detected and to release resources when the normal termination is reached. These monitoring and controlling activities have to be mediated by the deployment support actual mechanisms depend on the middleware and it does seem possible to reliably perform them over noisy low-bandwidth or mobile networks. 4. Current Prototypes GEA In the ASSIST architecture the Grid Abstract Machine GAM 2 is a software level providing the abstractions of security mechanisms resource discovery resource selection secure data and code staging and execution. The Grid Execution Agent GEA 4 is the tool to run complex component-based Grid applications and actually implements part of the GAM. GEA provides virtualization of all the basic functions of deployment . the underlying middleware systems see Tab. 1 translating the abstract specification of deployment actions into executable actions. We outlined GEA s requirements in Sect. . In order to implement them GEA has been designed as an open framework with several interfaces. To simplify and make fully portable its implementation GEA has been written in Java. As mentioned GEA takes in charge the ALDL description of each component Fig. 2 and performs the general deployment process outlined in Sect. 3 interacting with Grid middleware systems as needed. GEA accepts commands through a general purpose interface which can have multiple protocol adaptors . command-line HTTP SSL Web Service . The first command transfers to .