IPv4 is the fourth version of the Internet Protocol. An IPv4 address is a 32-bit number written as four decimal octets: 192.168.1.1.
CIDR Subnet Masks
| CIDR | Mask | Hosts |
|---|---|---|
| /24 | 255.255.255.0 | 254 |
| /16 | 255.255.0.0 | 65,534 |
| /8 | 255.0.0.0 | 16,777,214 |
Private (RFC 1918) Ranges
- 10.0.0.0/8 — large corporate networks
- 172.16.0.0/12 — medium organizations
- 192.168.0.0/16 — home/office networks
- 127.0.0.1 — loopback
💡 For VPS: Public IPv4 is a scarce resource (~$1–5/month for extra IPs). Many providers use NAT for VPS — ask your provider for the IP type before ordering.