Which of the following routing tools that are not only used for BGP routing protocols?  (Multiple choice)

Which of the following OSPF state transitions are possible? (Multiple Choice)

By default, the BGP speaker must set up an IBGP connection with other BGP peers so that IBGP peers can successfully advertise the routing information. In this manner, IBGP peers are interconnected throughout the AS.

Which of the following BGP attributes are recognized as mandatory type attributes? (Multiple choice)

If the OSPF neighbor relationship fails to be established, you can run the display ospf error command to view the information. If the following information is displayed, what may be the cause of the failure establishment of the neighbor?