<P> The modern standard form of specification of the network prefix is CIDR notation, used for both IPv4 and IPv6 . It counts the number of bits in the prefix and appends that number to the address after a slash (/) character separator . This notation was introduced with Classless Inter-Domain Routing (CIDR) in RFC 4632 . In IPv6 this is the only acceptable form to denote network or routing prefixes . </P> <Ul> <Li> 192.168. 0.0, subnet mask 255.255. 255.0 is written as 192.168. 0.0 / 24 </Li> <Li> In IPv6, 2001: db8:: / 32 designates the address 2001: db8:: and its network prefix consisting of the most significant 32 bits . </Li> </Ul> <Li> 192.168. 0.0, subnet mask 255.255. 255.0 is written as 192.168. 0.0 / 24 </Li> <Li> In IPv6, 2001: db8:: / 32 designates the address 2001: db8:: and its network prefix consisting of the most significant 32 bits . </Li>

Ipv4 network addresses ip addresses and subnet mask