A.HostA is not on the same subnet as its default gateway
B.The address of SwitchA is a subnet address
C.The Fa0/0 interface on RouterA is on a subnet that cannot be used
D.The serial interfaces of the routers are not on the same subnet
E.The Fa0/0 interface on RouterB is using a broadcast address

A.access-list 101 in
B.access-list 101 out
C.ip access-group 101 in
D.ip access-group 101 out

A.access-list 101 deny tcp 192.168.1.128 0.0.0.15 192.168.1.5 0.0.0.0 eq 23  access-list 101 permit ip any any
B.access-list 101 deny tcp 192.168.1.128 0.0.0.240 192.168.1.5 0.0.0.0 eq 23  access-list 101 permit ip any any
C.access-list 1 deny tcp 192.168.1.128 0.0.0.255 192.168.1.5 0.0.0.0 eq 21  access-list 1 permit ip any any
D.access-list 1 deny tcp 192.168.1.128 0.0.0.15 host 192.168.1.5 eq 23  access-list 1 permit ip any any

A.IR
B.DSSS
C.FHSS
D.DSSS and FHSS
E.IR，F(xiàn)HSS，and DSSS

A.L2TP
B.IPsec
C.PPTP
D.RSA

A.A level 5 password is not set
B.The vty password is missing
C.The console password is missing
D.An ACL is blocking Telnet access

A.172.31.17.4/30
B.172.31.51.16/30
C.172.31.64.0/18
D.172.31.80.0/22
E.172.31.92.0/22
F.172.31.192.0/18

A.Administratively shut down the interfaces.
B.Physically secure the interfaces.
C.Configure a virtual terminal password and login process.
D.Enter an access list and apply it to the terminal interfaces using the access-class command.
E.Create an access list and apply it to the terminal interfaces using the access-group command.

A.DLCI 17 describes the ISDN circuit between R2 and R3.
B.DLCI 17 describes a PVC on R2. It cannot be used on R3 or R1.
C.DLCI 17 is the Layer 2 address used by R2 to describe a PVC to R3.
D.DLCI 17 describes the dial-up circuit from R2 and R3 to the service provider.

A.It checks the configuration register
B.It attempts to boot from a TFTP server
C.It loads the first image file in flash memory
D.It inspects the configuration file in NVRAM for boot instructions