In order to join the wireless network STA. The wireless network information needs to be obtained first. Which of the following messages is used by the STA to actively obtain the SSID information?
()

Layer 2 ACL can match source MAC, destination MAC, source IP, destination IP and other information. ()

Which of the following statements about the S field in the MPLS packet header are correct? ()*

When the Access type port sends a message, it will ().

Under the command line interface of Huawei AR router, the save command is used to save the current system time.