Which utility is used to test whether a host is reachable across an IP network?

Which utility is used to test whether a host is reachable across an IP network?

• A. Ping
• B. Tracert
• C. Nslookup
• D. Ipconfig

Answer: (A)

Testing reachability across an IP network means confirming you can reach the destination and also getting a sense of the responsiveness. Ping does exactly that: it sends an ICMP echo request to the target and waits for an ICMP echo reply. If replies come back, the host is reachable and you can see the round-trip time, which tells you about latency. If there are no replies, it suggests a connectivity issue, the host may be down, or something like a firewall is blocking ICMP traffic. Ping works with both IPv4 and IPv6, making it a versatile quick check. The other tools perform different tasks. Tracert (traceroute) reveals the path to the destination, listing each hop along the route and its latency, which helps locate where problems occur but isn’t a direct confirmation that the end host is reachable. Nslookup focuses on DNS, translating domain names to IP addresses, not testing connectivity. Ipconfig shows your own machine’s network configuration (IP address, subnet mask, gateway), useful for diagnosing local setup but not for testing whether a remote host is reachable.

Testing reachability across an IP network means confirming you can reach the destination and also getting a sense of the responsiveness. Ping does exactly that: it sends an ICMP echo request to the target and waits for an ICMP echo reply. If replies come back, the host is reachable and you can see the round-trip time, which tells you about latency. If there are no replies, it suggests a connectivity issue, the host may be down, or something like a firewall is blocking ICMP traffic. Ping works with both IPv4 and IPv6, making it a versatile quick check.

The other tools perform different tasks. Tracert (traceroute) reveals the path to the destination, listing each hop along the route and its latency, which helps locate where problems occur but isn’t a direct confirmation that the end host is reachable. Nslookup focuses on DNS, translating domain names to IP addresses, not testing connectivity. Ipconfig shows your own machine’s network configuration (IP address, subnet mask, gateway), useful for diagnosing local setup but not for testing whether a remote host is reachable.