What does distributed computing mean?

What does distributed computing mean?

Distributed computing is a computing method. With the development of computing technology, some applications require very huge computing power to complete. If centralized computing is used, it will take a long time to complete. ,Distributed computing breaks the application into many small ,parts and assigns them to multiple computers for processing.

What is distributed?

In a distributed system, a group of independent computers presents a unified whole to the user, just like a system. The system has a variety of general physical and logical resources, which can dynamically allocate tasks. The dispersed physical and logical resources realize information exchange through the computer network. There is a distributed operating system in the system that manages computer resources in a global manner. Typically, there is only one model or paradigm for distributed systems to users. There is a layer of software middleware (middleware) on top of the operating system that is responsible for implementing this model. A well-known example of a distributed system is the World Wide Web. In the World Wide Web, everything looks like a document (Web page).

In computer networks, this unity, the models, and the software within them do not exist. Users see actual machines, and computer networks do not make those machines appear uniform. If these machines have different hardware or different operating systems, then these differences are completely visible to the user. If a user wants to run a program on a remote machine, he must log in to the remote machine and then run the program on that machine.

What distributed systems and computer network systems have in common is that most distributed systems are built on computer networks, so the physical structures of distributed systems and computer networks are basically the same.

The difference between them is that the design ideas of distributed operating systems are different from network operating systems, which determines that their structures, working methods and functions are also different. Network operating systems require network users to first understand network resources when using network resources. Network users must know the functions and configurations, software resources, network file structure, etc. of each computer in the network. If a user wants to read a shared file on the network, , the user must know which directory of which computer the file is placed in; the distributed operating system manages system resources in a global manner, it can arbitrarily schedule network resources for users, and the scheduling process is "transparent". When a user submits a job, the distributed operating system can select the most appropriate processor in the system as needed, submit the user's job to the processing program, and after the processor completes the job, the result is passed to the user. During this process, the user will not be aware of the existence of multiple processors, and the system will act like one processor.

Cohesion means that each database distribution node is highly autonomous and has a local database management system. Transparency means that each database distribution node is transparent to the user's application, and it cannot be seen whether it is local or remote. In a distributed database system, users do not feel that the data is distributed, that is, users do not need to know whether the relationship is divided, whether there are copies, which site the data is stored on, and which site the transaction is executed on.

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