What are the main methods of network security protection?

(1) Physical security policy: The purpose of physical security policy is to protect computer systems, network servers, printers and other hardware entities and communication links from natural disasters, man-made destruction and wiring attacks; Verify the user's identity and right to use, and prevent users from operating beyond their authority; Ensure that the computer system has a good electromagnetic compatibility working environment; Establish a complete safety management system to prevent illegal entry into the computer control room and various theft and sabotage activities.

(2) Access control strategy: Access control is the main strategy for network security prevention and protection, and its main task is to ensure that network resources are not illegally used and accessed. It mainly consists of network access control, network authority control, directory-level security control, attribute security control, network server security control, network detection and locking control, and network port and node security control.

(3) Firewall control: Firewall is a recently developed technical measure to protect computer network security. It is a barrier to prevent hackers in the network from accessing the organization network, and it can also be called the threshold to control two-way communication. On the network boundary, the corresponding network communication monitoring system is established to isolate the internal and external networks and prevent the invasion of external networks. At present, the mainstream firewalls are mainly divided into three categories: packet filtering firewall, proxy firewall and dual-port host firewall.

(4) Information encryption strategy: There are three common methods of network encryption: link encryption, endpoint encryption and node encryption. The purpose of link encryption is to protect the security of link information between network nodes; The purpose of endpoint encryption is to protect data from source users to destination users; The purpose of node encryption is to protect the transmission link between source node and destination node. The process of information encryption is realized by various encryption algorithms, which provides great security protection at a small cost. In most cases, information encryption is the only way to ensure the confidentiality of information. According to incomplete statistics, hundreds of encryption algorithms have been published so far. Mainly divided into conventional encryption algorithm and public key encryption algorithm.

(5) Network security management strategy: In terms of network security, besides the above technical measures, strengthening network security management and formulating relevant rules and regulations will play a very effective role in ensuring the safe and reliable operation of the network. The security management strategy of the network includes: determining the level and scope of security management; Formulate relevant network operation and use rules and the management system of personnel entering and leaving the computer room; Formulate the maintenance system and emergency measures of the network system.