There is a TTL field in the IP packet header. The correct statement about this field is.

What level of encapsulation format does the PPP protocol define in the OSI reference model?

After FIT AP obtains AC.'s IP address, what is the first operation to perform? ()

As shown in the figure, two hosts realize communication between TAs through single-arm routing. When the G0/0/1.2 sub-interface of RTA. receives the data frame sent by host B. to host A., RTA. will execute which of the following Operation? ()

As shown in the broadcast network. 0SPF runs on four routers. And in the same area. Same network segment.
OSPF will automatically elect one DR and multiple BDRs to achieve a better backup effect. ()(True or False)