Biblio

How to prevent the computer system from being interfered by external factors and maintain a strong working state is a problem that needs to be solved at present. At present, encryption and network security defense systems are important technical means of security defense. Based on this research background, the paper proposes an AES data encryption scheme in the Hadoop big data environment. The AES algorithm performs several rounds of plaintext encryption through the steps of round key addition, byte replacement, row displacement, column confusion, etc. Under the MapReduce architecture, the plaintext data is divided into multiple data fragments. The Map function is responsible for the AES algorithm encryption operation, and the Reduce function Combine encrypted data information. Finally, the paper designs a computer network security defense system that can actively discover the security threats in the network and effectively prevent them, so as to ensure the normal and safe operation of the network. At the same time, we use the encryption algorithm on the computer network security defense system. Experimental research has proved that this method can safely transmit network data packets. With the increase of computing cluster nodes, its encryption transmission efficiency continues to improve. This solution not only solves the problem of computer network data security encryption, but also realizes the parallel transmission of encrypted data in the information age.

With the rapid development of bulk power grid under extra-high voltage (EHV) AC/DC hybrid power system and extensive access of distributed energy resources (DER), operation characteristics of power grid have become increasingly complicated. To cope with new severe challenges faced by safe operation of interconnected bulk power grids, an in-depth analysis of bulk power grid security defense system under the background of EHV and new energy resources was implemented from aspects of management and technology in this paper. Supported by big data and cloud computing, bulk power grid security defense system was divided into two parts: one is the prevention and control of operation risks. Power grid risks are eliminated and influence of random faults is reduced through measures such as network planning, power-cut scheme, risk pre-warning, equipment status monitoring, voltage control, frequency control and adjustment of operating mode. The other is the fault recovery control. By updating “three defense lines”, intelligent relay protection is used to deal with the challenges brought by EHV AC/DC hybrid grid and new energy resources. And then security defense system featured by passive defense is promoted to active type power grid security defense system.