Broadcast address
A broadcast address is the special address at the top of an IPv4 subnet, with every host bit set to 1, that delivers one packet to every device on the subnet at once -- for a /24 network like 192.168.1.0/24, that's 192.168.1.255. RFC 919 and RFC 922 define this behavior, establishing subnet broadcasting as part of the original IP addressing scheme. Because the broadcast address is reserved for this purpose, it -- along with the all-zeros network address at the bottom of the range -- can't be assigned to an individual host, which is why a /24 subnet provides 254 usable host addresses rather than 256. IPv6 has no broadcast address at all; it replaced the concept with multicast, using scoped multicast groups instead of flooding an entire segment. AdminKit's subnet calculator computes a subnet's broadcast and network addresses automatically from any CIDR block.
By AdminKit team, Netbase JSC · Updated