IPv4 Subnetting Quiz

A subnet mask with 4 host bits provides 16 total addresses, but only 14 are usable for hosts after subtracting the network and broadcast addresses.

The network portion identifies the specific network, while the host portion differentiates individual devices within that network.

A subnet mask of /26 allocates 6 bits for host addresses, resulting in 64 total addresses (2^6). Two addresses are reserved, leaving 62 usable for hosts.

An IP address falling between the network and broadcast addresses within a subnet is a host address. It represents a specific device on that network.

A network administrator can create subnets of varying sizes to efficiently manage a larger network. The smallest subnet size in this example is 255.255.255.224, which is equivalent to a /27 subnet.

A subnet mask with 5 host bits allows for 32 total addresses (2^5), but only 30 are usable after excluding the network and broadcast addresses.

The subnet mask identifies the network to which a host belongs by separating the network portion from the host portion of an IP address.

The subnet mask is used to determine the network address of the destination network, which helps facilitate communication between devices.

The prefix length notation, often represented by a forward slash (/), indicates the number of bits used for the network portion of an IP address. A higher prefix length means more bits are dedicated to the network, leaving fewer bits for host addresses within that network.

A /27 subnet mask means 27 bits are used for the network portion, leaving 5 bits for host addresses. With 5 bits, you can represent 2^5 = 32 possible addresses.

To determine the subnet mask for a given number of host bits, subtract the number of host bits from 32 (total bits in an IPv4 address). The result is the prefix length, from which you can derive the subnet mask.

Subnetting divides a network into smaller subnets. Borrowing bits from the host portion of the original network mask allows creation of multiple subnets.

The number of subnets created from an original network depends on the number of bits borrowed for subnetting. Each borrowed bit doubles the number of possible subnets.

The slash notation (/20) represents the prefix length, indicating 20 bits are dedicated to the network portion of the IP address.

Variable Length Subnet Masking (VLSM) allows creating subnets of different sizes. This flexibility is useful for optimizing network resources based on the needs of different network segments.

ANDing the destination IP address with the subnet mask isolates the network address portion, removing the host-specific bits. This allows Layer 3 devices to determine the destination network and route traffic accordingly.