What are the main threats to Internet security at present?

1. Eavesdropping: Attackers obtain sensitive information by monitoring network data, which leads to information leakage. The main performance is that the information on the network is eavesdropped. This kind of network infringer who only eavesdrops without destroying the information transmitted in the network is called passive infringer. Malicious attackers usually use this as a basis and then use other tools to carry out more destructive attacks.

2. Retransmission: The attacker obtains part or all of the information in advance and then sends it to the receiver.

3. Tampering: The attacker modifies, deletes and inserts the communication information between legitimate users, and then sends the forged information to the receiver, which is pure information destruction. Such network infringers are called active infringers. Active infringers intercept online data packets, change them to make them invalid, or deliberately add some information that is beneficial to them, which plays a misleading role. Active attackers do the most damage.