What is the physical isolation card used for? What brands are there? Which brand is better?

A physical isolation card divides an ordinary computer into two or three virtual computers, which can be connected to an intranet or an extranet, so as to achieve absolute isolation between a secure environment and an unsafe environment, protect users' confidential data and information from threats and attacks from hackers on the Internet, and meet the dual needs of government, national defense, finance, insurance, telecommunications and enterprise users for data security and information acquisition. At present, there are many kinds of isolation cards on the market, about ten kinds. The main brands are Esk, Zhihua, Aegis, Weisi, Bailey, Zhongfu, Anxintong, Graphic, BBK, Jingtai and so on. There are two main isolation methods: one is to control the data line of the hard disk, and the other is to control the power supply of the hard disk; There are two switching modes: the switching mode is selected through the guidance interface, and the switching software in the system switches online. In principle, it is better to choose data isolation when buying, and you should choose a relatively large well-known brand.