Troubleshooting TCP/IP Overview - Quiz Explanation

The correct answers are indicated below, along with text that explains the correct answers.

1.	What is the main use of the `ping` command? Please select the best answer.
	A.	o display routing tables
	B.	To test a TCP/IP connection across a network
	C.	To assign IP addresses to devices
	D.	To route data to gateways
	The correct answer is B. The main use of `ping` is to test connections between network hosts. A is incorrect because `ping` does not display routing tales. C is incorrect because `ping` does not assign IP addresses to devices. D is incorrect because `ping` does not control routing; rather, it tests a connection that has been routed already.

2.	Which utility do you use to set an interface's IP address and netmask? Please select the best answer.
	A.	`netstat`
	B.	`ping`
	C.	`ifconfig`
	D.	`arp`
	The correct answer is C. `ifconfig` displays and modifies interface configurations. A is incorrect because `netstat` displays parameters and statistics on interfaces, but does not modify them. B is incorrect because `ping` tests network connections. D is incorrect because `arp` maps IP addresses to hardware addresses.

3.	Which type of association does the ARP system determine? Please select the best answer.
	A.	IP address to Ethernet address
	B.	IP address to hostname
	C.	Ethernet address to interface device
	D.	Ethernet address to hostname
	The correct answer is A. ARP binds IP addresses to Ethernet addresses. If the ARP system does not have an entry for a particular IP address, it queries all hosts to find out which one accepts data sent to that IP address. B is incorrect because DNS maps IP addresses to hostnames. C is incorrect because the Ethernet address of your interface is that of the first card on your system. D is incorrect because Ethernet addresses are mapped to IP addresses and then to hostnames. There is no direct protocol to resolve this association.

4.	What is the default action of the `ifconfig` command? Please select the best answer.
	A.	Displays active interface configurations
	B.	Displays all interface configurations
	C.	Displays Ethernet-to-IP address mappings
	D.	Tests the connection between two interfaces
	The correct answer is A. Typing `ifconfig` (or `/sbin/ifconfig`) at the command prompt displays the interface configuration information for all active interfaces. B is incorrect because the `-a` option is necessary to display any inactive interfaces. C is incorrect because displaying all interface configurations is the function of the `arp` command. D is incorrect because you use `ping` to test connection stability.