Please classify the main functions of the following operating systems correctly.

1. The enterprise needs to have its own dedicated mailbox, and the sending and receiving of mail needs to go through the enterprise's server;
2. The server must provide file transfer and access services, and provide accounts with different permissions for users in different departments of the enterprise;
3. The enterprise can directly enter the domain name in the browser when accessing the internal webpage of the enterprise.
To meet the above requirements, which of the following servers does the enterprise need to deploy? (Multiple choice)

The online scenario of internal users in the enterprise is shown in the figure. The user online process is as follows:
1. After the authentication is passed, the USG allows the connection to be established
2. The user accesses the internet and enters http://1.1.1.1
3. USG push authentication interface
4. The user successfully accesses http://1.1.1.1, and the device creates a session table
5. The user enters the correct user name and password
Which of the following is the correct process sequence?

In the security assessment method, the purpose of security scanning is to use scanning analysis and assessment tools to scan the target system in order to find relevant vulnerabilities and prepare for attacks

Which of the following factors are related to the initial priority of the USG9500 VGMP group? (Multiple choice)