Glossary
RFC 1918
RFC 1918 is a technical standard drafted by the Internet Engineering Task Force (IETF) that outlines the use of private IP addresses within private networks. This document, officially titled "Address Allocation for Private Internets," specifies the IP address ranges that are not routable on the global Internet and are intended exclusively for use within private networks. These addresses are designed to be used for internal network purposes to avoid the depletion of public IP addresses available on the Internet.
The specific IP address ranges defined by RFC 1918 that are reserved for private networks are:
These private IP addresses are commonly used in home networks, office settings, and by Internet Service Providers (ISPs) to provide local area network (LAN) functionality without using public IP space. Devices within the same private network can communicate with each other using these IPs, but they cannot directly reach the global Internet without the aid of a network address translation (NAT) service, typically performed by routers.
NAT helps these private networks connect to the Internet by translating the private IP addresses to public addresses outside the network, thereby conserving public IP addresses and adding a layer of security by masking internal IP addresses from external networks.
RFC 1918 addresses are integral to network design and management, providing essential guidelines that help system and network administrators structure networks efficiently while conserving global IP resources.