An engineer's desktop pc connects to a switch at the main site. a router at the main site connects to each branch office through a serial link, with one small router and switch at each branch. which of the following commands must be configured on the branch office switches, in the listed configuration mode, to allow the engineer to telnet to the branch office switches? (choose three answers.)

a. the ip address command in vlan configuration mode
b. the ip address command in global configuration mode
c. the ip default-gateway command in vlan configuration mode
d. the ip default-gateway command in global configuration mode
e. the password command in console line configuration mode
f. the password command in vty line configuration mode

a. The ip address command in VLAN configuration mode

e. The password command in console line configuration mode

f. The password command in vty line configuration mode

Explanation:

a.  Normally switches don't require to be configured with an IP address. However, it is necessary to configure an IP address on the switch’s VLAN  interface in order to access it remotely.

e. The network device console port must be secured, by requesting a secure password from the user. This reduces the chances of unauthorized personnel physically connecting a cable to the device and obtaining access to it.

f. The vty lines allow access to a Cisco device through Telnet. By default, many Cisco switches support up to 16 vty lines that are numbered from 0 to 15. The number of vty lines that a Cisco router supports varies depending on the type of router and the IOS version.