What is the purpose of the OSPF link-state update packet?（）

单项选择题Why would you make a non-backbone area a stub or not-so-stubby area?（）

A. to aggregate routes learned from the ABR
B. to lower the cost of routes advertised by the ABR
C. to connect a non-contiguous area to the backbone
D. to decrease the size of the link-state database in that area

单项选择题During OSPF adjacency formation, in what state is a router when it is negotiating to be in charge of the database synchronization process?（）

A. Init
B. 2Way
C. ExStart
D. Exchange

单项选择题By default, which command can be used to display information about packets that have been logged with the syslog firewall filter action?（）

A. show log
B. show firewall
C. show log messages
D. show firewall log

多项选择题A firewall filter is applied as an input filter on a transit interface. What three types of traffic will this affect? （）

A. inbound traffic transiting the router
B. outbound traffic transiting the router
C. traffic destined to the Routing Engine
D. traffic destined to the interface address on which the filter is applied

多项选择题Firewall filters can be used to accept, discard, or reject packets based on （）

A. protocol type
B. MAC address
C. TCP or UDP port
D. source and destination IP address