The essence of the network of network security knowledge: computer network does not appear with the appearance of computers, but develops with the urgent demand of society for resource sharing, information exchange and timely transmission. It is the product of the close combination of modern computer technology and communication technology. More precisely, a computer network is a system that connects computers and other devices that are not together by using communication equipment and communication lines, and realizes resource sharing and information exchange by using corresponding software.

The early network only means that several computers in a unit are connected by a cable to realize local resource sharing and information exchange. Today's network connects tens of millions of computers in hundreds of countries around the world, forming a "giant" like a spider's web, realizing all-round resource sharing and information exchange around the world. This is the Internet, also known as the Internet. For a company, as long as you connect the external connection of the company network to the Internet, the nature of your network will change fundamentally, and its extension and connotation will also change fundamentally. The network we are talking about today refers to the Internet, and the Internet is also on the Internet.

What are the benefits of network security knowledge?

What are the benefits of a network with knowledge of network security? This benefit is actually reflected in resource sharing and information exchange and timely delivery. Taking resource sharing as an example, only one printer is installed in one office or several offices, which does not delay work; A company or library only buys an expensive software, and everyone in the company can use it at will; At the train station or airline ticket office, the ticket information is summarized and put on the internet, and anyone can check online at any time to know how many tickets are left for a train or flight. Such a thing, both saving money and reducing duplication of work, is good. Information exchange and timely transmission in the network are more favorable. Thanks to the computer network, People's Daily can send samples to all parts of China and even foreign printing points within a few minutes after printing in Beijing. In this way, you will know the news that happened half an hour before the newspaper was printed at 6 o'clock in the morning. It is also because of the Internet that farmers in Huadu can sell flowers to all countries in the world at home. Children in Shaoguan can sit at home and attend the online school affiliated to Guangzhou Normal University, where they can receive extra-curricular tutoring from special-grade teachers all over the country. It can be said that it is precisely because of the long-distance communication of information and the timely transmission through the network. In this sense, the network has changed time and space, the distance between people has become closer, the earth has become smaller and there has been more information.

Basic content of network security

First, cyber attacks.

1. Attacks on the network can be roughly divided into two categories: service supply and non-service attacks. Attacks can be divided into eight categories: system intrusion attack, buffer overflow attack, deception attack, denial of service attack, firewall attack, virus attack, Trojan horse attack and backdoor attack.

2. Application Dependent Attrack refers to an attack on a server that provides a certain service for the network, resulting in "denial of service" of the server and abnormal network work. At track's denial-of-service attack has the following effects: consuming bandwidth, consuming computing resources, and crashing systems and applications. , which prevents legitimate users of a service from accessing the services they have access to.

3. Application-independent Attrack is not aimed at specific application devices, but at the underlying protocols such as the network layer. This kind of attack often uses the loopholes in the protocol and operating system to achieve the purpose of the attack, which is a more hidden and dangerous attack means.

Second, information security.

Information security in 1. network mainly includes two aspects: information storage security and information transmission security.

2. Information storage security refers to how to ensure that information statically stored in networked computers will not be illegally used by unauthorized network users.

3. Information transmission security refers to how to ensure that information is not leaked and attacked during network transmission.

The main threats to information transmission security are: intercepting information, tampering with information and forging information.

The main technologies to ensure the information security of network system are data encryption and decryption.