What is a grid? What's the grid?

Grid is the integration of the entire Internet into a huge supercomputer, the realization of computing resources, storage resources, data resources, information resources, knowledge resources, expert resources for the full sharing. Of course, we can also construct regional grids (such as Zhongguancun Science Park Grid), enterprise internal grid, LAN grid, even home grid and personal grid. The basic feature of grid is not necessarily its scale, but resource sharing, eliminating the resource island. Grid is a concept from the power grid, originally hoped that the computational power and computing resources like electricity, "open the power switch can be used", do not care who is, how to provide these services.

Because Grid is a new technology, it also has two characteristics of new technology. First, different groups use different nouns to address it. Second, the exact meaning and content of the grid are not fixed, but are changing.

Given the uncertainty of the grid concept, the father of the grid, Ian Foster, defines the grid concept:

(1) Coordination of the resources of the non-centralized control-grid integration of various resources, coordinate the various user, these resources and users in different control domains, such as personal computers and central computers, different management units of the same or different companies; grids also address the security, policy, and usage costs that arise in this distributed environment, Issues such as membership permissions. Otherwise, only the local management system, not the grid, can be counted.

(2) The use of standard, open, universal protocols and interfaces-grid based on a multi-functional protocol and interface, these protocols and interfaces to address authentication, authorization, resource discovery and resource access and other basic issues. I will further elaborate on the importance of these protocols and interfaces for standardization and openness. Otherwise, only a specific application system, not a grid.

(3) Get the extraordinary quality of service--grid allows its resources to be used in a coordinated, in order to obtain a variety of service quality, to meet the needs of different users, such as system response time, liquidity, effectiveness, security, and resource relocation, so that the effectiveness of the joint system than its various parts of the total effect is much greater.

The essential features of the grid:

Distribution and resource sharing: distribution is the most original feature of the grid, the grid is through the centralized decentralized resources to complete the calculation, the sharing of resources is a means of pooling resources

Highly abstract: The computational force and all the computational resources are highly abstracted into the user's visible "power wiring board", other things transparent to the user.

To have the same or similar regularity on a large scale and on a small scale

Dynamics and diversity: As with power grids, user needs are changing, so dynamic is a fundamental problem for the grid to consider

The multiplicity of autonomy and management: the autonomy and external controlled integration of grid nodes is a feature of grid, layered resources need hierarchical management, and stratification comes from the problem of grid node's attribution and performance considerations.