Which frame field do error detection schemes view to perform their function?（）

单项选择题Which of one the following fields is contained within an IEEE Ethernet frame header?（）

A. source and destination MAC address
B. source MAC address and destination network address only
C. source and destination network address only
D. source network address and destination MAC address
E. source and destination MAC address and source and destination network address

单项选择题Which device enables a router serial interface to connect to the ISDN BRI?（）

A.NT2
B.NT1
C.TE
D.TA
E.TE1

多项选择题What functions do routers perform in a network?（）

A. Packet Switching
B. Access Layer Security
C. Path Selection.
D. VLAN Membership Assignment.
E. Bridging between LAN segments.
F. Micro-segmentation of Broadcast Domains.

单项选择题If NVRAM lacks boot system commands, where does the router look for the Cisco IOS by default?（）

A.ROM
B.RAM
C.Flash
D.Bootstrap
E.Startup-.config

多项选择题When selecting a Network Interface Card (NIC), which of the following factors need to be considered?（）

A. The type of application used on the network
B. The type of system bus used by the computers
C. The type of memory installed in each computer
D. The type of media used in the network topology
E. The type of protocols used in the network
F. The physical layout of the network hosts