Which of the following is the encryption technology used by digital envelopes?

Which ofthe following are the standard port numbers for the FTP protocol? (Multiple choice)

Which of the following descriptions of the firewall fragment cache function are correct? (Multiple choice)

For the occurrence of network security incidents, the remote emergency response is generally adopted first. If the problem cannot be solved for the customer through remote access, after the customer confirms, it is transferred to the local emergency response process.

ASPF (Application Specific Packet Filter) is a packet filtering technology based on the application layer, and implements a special security mechanism through the server-map table.
Which of the following statements about the ASPF and server-map tables are correct? (Multiple Choice)