For the description of URPF technology, which of the following options are correct? (multiple choice)

The main function is to prevent network attacks based on source address spoofing.
In strict mode, it does not check whether the interface matches. As long as there is a route to the source address, the message can pass.
The loose mode not only requires corresponding entries in the forwarding table, but also requires that the interface must match to pass the URPF check.
Use URPF's loose mode in an environment where routing symmetry cannot be guaranteed.

Answer(s): A,D

Which of the following descriptions about the black and white lists in spam filtering is wrong? c

Set local blacklist and whitelist: Both blacklist and whitelist can be configured at the same time, or only one of them can be configured.
In the "Whitelist" text box, enter the P address and mask of the SMTP Server to be added to the whitelist. You can enter multiple IP addresses, one IP address Address one line. v
Enter the IP address and mask of the SMITP Server to be added to the blacklist in the "Blacklist" text box, you can enter multiple IP addresses, one IP
Address one line.
The priority of the blacklist is higher than that of the whitelist.

Answer(s): D