You are the network administrator at Certkiller .com. Two Microsoft Windows XP workstations on
the Certkiller .com network have the same IP address, resulting in an IP address conflict. Which
command can you use to identify the conflicting computers?

A.
ping

B.
arp -a

C.
ipconfig /all

D.
winipcfg /all

Explanation:
The arp utility is useful for resolving duplicate IP addresses. The arp -a command displays the
local ARP table which lists the IP address to MAC address mappings.
Incorrect Answers:
A: Ping is used to test connectivity between two hosts using the IP address of the remote hosts. If
the remote host’s IP address is in conflict with another host, ping will return an error.
C: ipconfig /alldisplays the IP configuration and MAC address for the local workstation. It does not
display IP configurations or the MAC address of remote workstations.
D: winipcfg is the Windows 9x version of ipconfig and displays the IP configuration and MAC
address for the local workstation but not the IP configuration or the MAC address of remote
workstations.References:David Groth and Toby Skandier, Network+ Study Guide (4th Edition),
Sybex, Alameda CA, 2005, pp. 186-188, 194.