Grid Computing Lexicon
Reading about grid computing can get very confusing if you don't know the lingo. Here's a quick rundown on some of the terms you might encounter when discussing grid computing:
- Cluster: A group of networked computers sharing the same set of resources.
- Extensible Markup Language (XML): A computer language that describes other data and is readable by computers. Control nodes (a node is any device connected to a network that can transmit, receive and reroute data) rely on XML languages like the Web Services Description Language (WSDL). The information in these languages tells the control node how to handle data and applications.
- Hubs: A point within a network where various devices connect with one another.
- Integrated Development Environment (IDE): The tools and facilities computer programmers need to create applications for a platform. The term for an application testing ground is sandbox.
- Interoperability: The ability for software to operate within completely different environments. For example, a computer network might include both PCs and Macintosh computers. Without interoperable software, these computers wouldn't be able to work together because of their different operating systems and architecture.
- Open standards: A technique of creating publically available standards. Unlike proprietary standards, which can belong exclusively to a single entity, anyone can adopt and use an open standard. Applications based on the same open standards are easier to integrate than ones built on different proprietary standards.
- Parallel processing: Using multiple CPUs to solve a single computational problem. This is closely related to shared computing, which leverages untapped resources on a network to achieve a task.
- Platform: The foundation upon which developers can create applications. A platform can be an operating system, a computer's architecture, a computer language or even a Web site.
- Server farm: A cluster of servers used to perform tasks too complex for a single server.
- Server virtualization: A technique in which a software application divides a single physical server into multiple exclusive server platforms (the virtual servers). Each virtual server can run its own operating system independently of the other virtual servers. The operating systems don't have to be the same system -- in other words, a single machine could have a virtual server acting as a Linux server and another one running a Windows platform. It works because most of the time, servers aren't running anywhere close to full capacity. Grid computing systems need lots of servers to handle various tasks and virtual servers help cut down on hardware costs.
- Service: In grid computing, a service is any software system that allows computers to interact with one another over a network.
- Simple Object Access Protocol (SOAP): A set of rules for exchanging messages written in XML across a network. Microsoft is responsible for developing the protocol.
- State: In the IT world, a state is any kind of persistent data. It's information that continues to exist in some form even after being used in an application. For example, when you select books to go into an Amazon.com shopping cart, the information is stateful -- Amazon keeps track of your selection as you browse other areas of the Web site. Stateful services make it possible to create applications that have multiple steps but rely on the same core data.
- Transience: The ability to activate or deactivate a service across a network without affecting other operations.
So how exactly does a grid computing system link computer resources together? Find out in the next section.