Which of the following descriptions of single sign-on is correct?

• A. The visitor recited the Portal authentication page and sent the username and password to FT to identify his/her identity, and the password was not stored on the FT, and the FI sent the username and password to the third-party authentication server, and the authentication process was carried out on the authentication server.
• B. Visitors obtain the SMS verification code through the Portal authentication page, and then enter the SMS verification code to pass the authentication.
• C. The visitor sends the username and password that identifies them to the FW through the portal authentication page, on which the password is stored and the verification process takes place on the FW.
• D. The visitor sends the username and password that identifies his identity to the third-party authentication server, and after the authentication is passed, the third-party authentication server sends the visitor's identity information to FW. F7 only records the identity information of the visitor and does not participate in the authentication process

At what layer does packet filtering technology in the firewall filter packets?

• A. Physical layer
• B. Transport layer
• C. Network layer
• D. Data link layer

Which layer of data packets does a packet filtering firewall check?

• A. Physical layer
• B. Application layer
• C. Network layer
• D. Data link layer

Drag the warning level of the network security emergency response on the left into the box on the right, and arrange it from top to bottom in order of severity.

What is correct in the following description of Security Alliance in IPSec?
There are two ways to set up an IPSec SA

• A. manual and IKE.
  IPSec SA is uniquely identified by a triple.
• B. Security Alliance SA is a communication peer agreement for certain elements that describes how peers can communicate securely using secure services such as encryption.
• C. IPSec SA is a one-way logical connection, usually established in pairs (Inbound and Outbound).