Question 1

What is CIDR Notation?

Accepted Answer

CIDR notation specifies the number of fixed network prefix bits in an IP address (e.g. 192.168.1.0/24), dictating network size and host availability.

Question 2

What is a Broadcast Address?

Accepted Answer

In IPv4 subnets, the broadcast address is the final IP in the range (e.g. 192.168.1.255/24), reserved for sending packets to all hosts on the subnet simultaneously.

Question 3

Why subtract 2 IPs from the total host capacity?

Accepted Answer

In standard IPv4 subnets, the first address (Network ID) identifies the subnet, while the last address (Broadcast ID) is for broadcast. A /24 subnet has 256 total IPs but 254 usable host addresses.

Question 4

How does IPv6 subnetting differ from IPv4?

Accepted Answer

IPv4 uses 32-bit addresses divided into 4 octets. IPv6 uses 128-bit addresses formatted in 8 hexadecimal blocks, supporting vast /64 subnets without requiring broadcast addresses.

Subnet Calc