ENVIRONMENTS

Commodity Grid kits – middleware for building Grid computing environments

The concept of the Grid is based on coordinated resource sharing and problem solving in dynamic multi-institutional virtual organizations. The  Commodity Grid project is creating  Commodity Grid Toolkits (CoG Kits) that define mappings and interfaces between Grid services and particular commodity frameworks. Technologies and frameworks of interest currently include Java, Python, CORBA,Perl and Web Services.

Grid Computing Environments and Portals

GCEs are aimed at providing scientists and other Grid users with an environment that accesses the Grid by using a coherent and interoperable set of frameworks that include Portals, Problem-Solving Environments, and Grid and Commodity Services. This goal is achieved by developing Grid and commodity standards, protocols, APIs, SDKs, and methodologies, while reusing existing ones.Grid Computing Environment is defined as “An integrated set of tools that extend the user’s computing environment in order to provide access to Grid Services.”

 

GCEs include Portals,shells and collaborative and  immersive environments running on the user’s desktop on common operating systems such as Windows and Linux or on PDAs or CAVEs.

A Grid portal provides information about the status of the Grid resources and services.  This information includes the status of batch queuing systems, load, and network performance between the resources.

 

The Grid portal development kit

The Grid Portal Development Kit seeks to provide generic user and application portal capabilities and was designed with the following criteria:

• The core of GPDK should reside in a set of generic, reusable, common components to access those Grid services that are supported by the Globus toolkit including the Grid Security Infrastructure (GSI).

• Provide a customizable user profile that contains user specific information such as past jobs submitted, resource and application information, and any other information that is of interest to a particular user.

• Provide a complete development environment for building customized application spe-cific portals that can take advantage of the core set of GPDK Grid service components. The true usefulness of the Grid Portal Development Kit is in the rapid development and deployment of specialized application or user portals intended to provide a base set of Grid operations for a particular scientific community.

• The GPDK should leverage commodity and open source software technologies to the highest degree possible.

GRID PORTAL ARCHITECTURE

Grid portal architecture

The Grid Portal Development Kit provides Grid enabling middleware for the middle-tier and aids in providing a Grid enabled application server. The GPDK is part of a complex vertical software stack. At the top of the stack is a secure high- performance web server capable of handling multiple and simultaneous HTTPS requests. Beneath the web server is an application server that provides generic object invocation capabilities and offers support for session management. The deployed GPDK template portal creates a web application that is managed by the application server and provides the necessary components for accessing Grid services.

The Grid Portal Development Kit uses the Model-View-Controller (MVC) design pattern to  separate  control  and  presentation  from the  application  logic  required  for invoking Grid services. The GPDK is composed of three core components that map to the MVC paradigm. The Portal Engine (PE), provides the control and central organization of the GPDK portal in the form of a Java servlet that forwards control to the Action Page Objects (APO) and the View Pages (VP). The Action Page Objects form the ‘model’ and provide encapsulated objects for performing various portal operations. The View Pages are executed after the Action Page Objects and provide a user and application specific display (HTML) that is transmitted to the client’s browser.

GPDK SERVICES

GPDK services include:-

a)     Security

b)     Job Submission

c)      File Transfer

d)     GPDK user profiles

e)     Information Services

Building Grid computing portals: the NPACI Grid portal toolkit

Web-based Grid computing portals, or Grid portals, have been established as effective tools for providing users of computational Grids with simple, intuitive interfaces for accessing Grid information and for using Grid resources. Grid middleware  such as the Globus Toolkit provides powerful capabilities for integrating a wide variety of computing and storage resources, instruments, and sensors, but Grid middleware packages generally have complex user interfaces (UIs) and Application Programming Interfaces (APIs). Grid portals can enable automated execution of specific applications, provide explicit links to discipline-specific data collections, integrate (and hide) data workflow between applications, and automate the creation of collections of application output files.

GridPort attempts to address these issues by meeting several key design goals:

• Universal access:  enables Web-based portals that can run anywhere and any time, that  do  not  require  software  downloads,  plug-ins,  or  helper  applications,  and  that work with ‘old’ Web browsers that do not support recent technologies (e.g. client-side XML).

• Dependable information services:  provide portals, and therefore users, with centralized access to comprehensive, accurate information about Grid resources.

• Common Grid technologies and standards:  minimize impact on already burdened resource administrators by not requiring a proprietary GridPort daemon on HPC resources. • Scalable and flexible infrastructure:  facilitates adding and removing application portals, Grid software systems, compute and archival resources, services, jobs, users, and so on.

• Security:  uses GSI, support HTTPS/SSL (Secure Sockets Layer) encryption at all layers, provide access control, and clean all secure data off the system as soon as possible.

• Single login:  requires only a single login for easy access to and navigation between Grid resources.

• Technology transfer:  develops a toolkit that portal developers can easily download, install, and use to build portals.

• Global Grid Forum standards:  adhere to accepted standards, conventions, and best practices.

• Support for distributed client applications and portal services:  enables scientists  to build their own application portals and use existing portals for common infrastructure services.

Grid computing portals such as the HotPage and toolkits such as GridPort have become popular in the HPC community. The HotPage continues to maintain a position of high visibility because it provides the appropriate kind of information that a traditional HPC user requires. GridPort has proven to be useful and popular with application portal developers because it is based on simple technologies that are easy to deploy and use for development.

The GridPort project has been expanded to provide a developer’s framework that will support a variety of Grid computing environments (GCEs) including portals (user and application), Grid applications, legacy applications, problem solving environments, and shells. The initial redesign phase will focus on Grid portals and the Grid Web services needed to support them. Subsequent efforts will further generalize GridPort for the development of Grid applications and other GCEs, after the Grid infrastructure needed to support Grid applications has matured.

Current GCE architecture:

  • Client layer
  • Application Layer(enhancement of the current portals layer)
  • Application services layer(enhancement of portal services layer)
  • Grid services(technologies layer)
  • Resources layer

<<Previous


Next>>

  1. No comments yet.
  1. No trackbacks yet.

Leave a Reply

Fill in your details below or click an icon to log in:

WordPress.com Logo

You are commenting using your WordPress.com account. Log Out / Change )

Twitter picture

You are commenting using your Twitter account. Log Out / Change )

Facebook photo

You are commenting using your Facebook account. Log Out / Change )

Google+ photo

You are commenting using your Google+ account. Log Out / Change )

Connecting to %s

%d bloggers like this: