Linux Networking 3

Question 1

What does CIDR notation `/24` indicate about a network?

Accepted Answer

The first 24 bits are the network portion

Answer

In CIDR notation, `/24` means 24 bits are used for the network prefix, leaving 8 bits for host addresses (254 usable hosts).

Question 2

Which command would you use to test if a remote host is reachable at the network layer?

Accepted Answer

ping

Answer

`ping` sends ICMP echo request packets to test basic connectivity and measure round-trip time to a host.

Question 3

What is the loopback IP address in IPv4?

Accepted Answer

127.0.0.1

Answer

127.0.0.1 is the IPv4 loopback address (also `localhost`) used by the system to communicate with itself.

Question 4

Which tool scans for open ports and services on a target host?

Accepted Answer

nmap

Answer

`nmap` (Network Mapper) is a widely-used tool for port scanning, service detection, and network discovery.

Question 5

What does the ARP protocol resolve?

Accepted Answer

IP addresses to MAC addresses

Answer

ARP (Address Resolution Protocol) maps an IPv4 address to the corresponding hardware (MAC) address on a local network segment.

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