Middleware for Grid Computing and the relationship to

Middleware for Grid Computing and the relationship to Middleware at large ECE 1770 : Middleware Systems By: Sepehr (Sep) Seyedi Date: Thurs. January 23, 2003

What is Grid Computing? Definition of the Grid l l l Controlled sharing of geographically distributed resources Virtual Organization Analogy with power grids l Consistent, pervasive, dependable, and transparent access to electricity from different sources Characteristics of a Grid l l No centralized control center Heterogeneity (of resources) Scalability Dynamic and Adaptable

Applications Presented early to see relevance to the design methodologies in grid middleware Classifications of Applications/Uses: l Computational Service l l Data Service l l Example: like web services Information Service l l Scalable storage and access to distributed datasets Application Service l l Inherent part of ALL applications Example: WWW portal Knowledge Service l Example: data mining

A Layered View of a Grid Available as APIs: global resource management: resource brokers, … Grid Application User-level Middleware Core Middleware Grid Fabric Process management, co-allocation of resources, storage access, security, information registry and discovery, …. Computers, supercomputers, storage devices, instruments …

Middleware Overview Many organizations involved l ex: Global Grid Forum and Globus Components l Security l l Secure communications (SSL) Distributed security infrastructure l l l Transferring data throughout the grid and to users Globus: Grid. FTP l l Deals with high-performance, security and reliability Information Management l l l Manage user credentials to selectingappropriate resources Data Management l User-level & Core ASPECTS Information DB about resources Availability, capabilities, … Resource Management

Resource Management Application Resource Broker job Multi-request Query ? Types of resources needed ? Specifications of requests Resource Information Manager Resource Co-allocator request Local Resource Manager Service/Resource

Open Grid Services Architecture (OGSA) Global Grid Forum (www. gridforum. org) driving force behind OGSA Promoting a standard and open architecture for interfaces to resources Assuring proper uniform behavior of all resources and interoperability in a heterogeneous environment

The Grid Service Implemented as special a Web service Standardized behavior Standardized interfaces Standard interfaces in terms of Web Services Description Language (WSDL) GSDL Implementation independent l l The grid service is able to live on any host environment that supports web services. Examples: J 2 EE, . NET, C, Python, … which cover most existing operating systems

The Grid Service Interface Grid Services must support: l Discovery l l Dynamic Service (instance) creation l l l Factory: creates service instances Lifetime management l l Registry: holds information about service instances Life length, termination of service in case of failure of resource Notification Manageability l Monitoring and managing service instances Grid Services can also provide (custom) application services, like web services

How does a Grid Service work? Client uses a Grid service interface A grid service instance is created from a Factory with the help of a Registry The grid service instances run with appropriate resources automatically allocated New instances can allocated and destroyed dynamically, to benefit performance l Example: A web serving environment could dynamically allocate extra instances to provide consistent user response time

Factory Real Services Service Instance … Invocation DB 1 … Simple Invocation Example User Database Service DB n Service Instance -EJB -Java Class Service Instance Registry Compute service provider …

Hierarchical Use of Grid Services Simple Hosting Environment Virtual Hosting Environment Collective Services Environment

Relationship with Middleware at large Distributed Computing l l l Grid computing itself can be thought of as a distributed system Differs by providing a controlled, dynamic resource -sharing framework that addresses the requirements of a grid Comparison to CORBA, J 2 EE, and. NET Grid computing can be used as a building block in other middleware systems l ‘Too much middleware’ Benefiting other middleware technologies l Web services is making advances due to grid services

Conclusions Characteristics of a grid relevant to middleware Common design methodologies in grid middleware Grid Services and open standardization New and existing middleware systems are beginning to adopt core grid middleware to become easily ‘grid-enhanced’

Thank You! Any Questions ? ? CHECKOUT www. gridcomputing. com for more information on Grid Computing!