The network address is the first IP address in a subnet. It identifies the entire network segment and cannot be assigned to any host.
For example, in 192.168.1.0/24:
* 192.168.1.0 # Network Address (non-assignable)#
* 192.168.1.1 - 192.168.1.254 # Usable host addresses
* 192.168.1.255 # Broadcast address
Clarifying:
* A. First address of the subnet ##Correct
* B. First usable address ##That would be second address
* C. Last address of the subnet ##That's the broadcast
MTCNA Course Manual - Subnet Addressing:
"The first address in a subnet is reserved as the network ID. It cannot be assigned to a host." Rene Meneses Guide - Network and Broadcast Addresses:
"Network address = first IP in block, broadcast = last. Usable range lies in between." Terry Combs Notes - Host and Network Addressing:
"Always subtract 2 IPs: one for network and one for broadcast. Never assign .0 (network address) to a host."