Cloud computing tutorials learn getting started with video courseware: what is middleware?

Middleware is a kind of independent system software or service program, which is used by distributed application software to share resources among different technologies. Middleware is located on top of the client / server operating system and manages computer resources and network communications. Is software that connects two independent applications or independent systems. Even though they have different interfaces, connected systems can still exchange information with each other through middleware.

One of the key ways to implement middleware is information transmission. Through middleware, applications can work in multi-platform or OS environments. Middleware is between the operating system and the application software, which provides service functions for the application software, such as message middleware, transaction middleware, application server and so on. Because it is between two kinds of software, it is called middleware.

So why use middleware? Specifically, middleware shields the complexity of the underlying operating system, making program developers face a simple and unified development environment, reduce the complexity of program design, and focus their attention on their own business. there is no need to repeat work for the transplantation of programs on different system software, thus greatly reducing the technical burden.

Middleware brings not only the simplicity of development and the shortening of development cycle, but also reduces the workload of system maintenance, operation and management, but also reduces the overall cost of computer.

Instead of sitting idle at home, it is better to start learning immediately. When the opportunity explodes, whether we can grasp it or not depends on whether we are ready and strong enough. So, from now on, Qianfeng 900G+ video tutorials are free! Just leave a message below. I hope it can help you grow up in the "adversity" and start the new year calmly.

Classification of main middleware

1. Hadoop

Hadoop is a distributed computing platform, which is developed in Java language and contains three core components: Common, MapReduce and HDFS (HDFS and MapReduce are the two core components).

2. LVS

LVS is the acronym of Linux Virtual Server, which means Linux virtual server, that is, many physical Linux computers are logically integrated into a single supercomputer, so that users feel that there is only one server with strong computing power. LVS is a load balancer implemented by software, which works in the fourth layer (application layer) of the network OSI. It was developed by Chinese Zhang Song, and the code has been incorporated into the Linux kernel. Using it, coupled with a cheap computer, you can build an enterprise-class load balancer. And those big foreign companies' load balancers cost more than 100,000 yuan, or even hundreds of thousands of yuan, and cheap ones cost tens of thousands of yuan. after LVS came out, these products had to be reduced.

3. Linux-HA

The core idea of Linux-HA integrated failover clustering software is to detect faulty machines in real time and let good machines take over the work in time, so as to provide high availability. Linux-HA means Linux high availability project.

4. Static website server

When we visit a company's website, we are probably dealing with the Apache program on that company's server. The web browser and Apache have become the standard Cpact S mode, with the browser as the client and Apache as the server. Apache first sends us the file index.html corresponding to the home page. After we see the contents of the home page, we click on a link on the home page, and it sends us the file corresponding to the link.

5. Dynamic application server

Open source dynamic application servers include JBoss, Tomcat, Geronimo, and JOnAS.