What are digital technology and network technology
Digital technology refers to the use of 0 and 1 two digit coding, through electronic computers, optical cables, communication satellites and other equipment, to express, transmit and process all information technology. Digital technology generally includes digital coding, digital compression, digital transmission, digital modulation and demodulation.
Computer network technology is the combination of communication technology and computer technology. Computer network is a collection of scattered and independent computers connected to each other according to network protocol. The connecting medium can be cable, twisted pair, optical fiber, microwave, carrier or communication satellite. Computer network has the function of sharing hardware, software and data resources, and has the ability of centralized processing, management and maintenance of shared data resources. Computer network can be classified according to different standards, such as network topology, network scope and interconnection distance, network data transmission and network system owner, different service objects, etc. It is generally divided into: (1) local area network (LAN)（ 2) Man（ 3) Wide area network (WAN). The geographical scope of local area network is generally within 10 kilometers, which belongs to a small area network formed by a department or a group of groups, such as a school, a unit or a system. Wan covers a wide range, generally from tens of kilometers to tens of thousands of kilometers, such as a city, a country or an intercontinental network. At this time, the transmission devices and media used for communication are generally provided by the telecommunications department, which can achieve a wide range of resource sharing. Metropolitan area network is between LAN and WAN. It usually covers a city or an area, ranging from tens of kilometers to hundreds of kilometers.
Computer network consists of a group of nodes and chains. There are two kinds of nodes in the network: transfer node and access node. Communication processor, concentrator and terminal controller are switching nodes, which transfer and exchange information in the network. The main computer and the terminal are the access nodes, which are the source node and the target node of information transmission.
Computer network technology realizes resource sharing. People can access any resources on the Internet in the office, at home or anywhere else, which greatly improves the work efficiency and promotes the development of office automation, factory automation and home automation.
The 21st century has entered the era of computer network. Computer network is very popular, computer applications have entered a higher level, computer network has become a part of the computer industry. The new generation computer has integrated the network interface into the main board, and the network function has been embedded into the operating system. The construction of the intelligent building has been carried out at the same time, in the same place and in the same scheme as the computer network wiring. With the close combination and synchronous development of communication and computer technology, China's computer network technology has developed by leaps and bounds