Topic

IP addresses

An IP address identifies a network interface for communication using the Internet Protocol and is used by routers to deliver packets.

At a glance

Current protocol families
IPv4 and IPv6
Primary purpose
Network addressing and routing

Overview

Internet Protocol addresses are numeric identifiers used by networked systems when sending packets. IPv4 and IPv6 use different address sizes and notation, but both provide addresses that network software can route. A public hostname can resolve to one or more IP addresses, and the address visible to another service may differ from a device local address because of network translation or proxying.

Public and private context

An address only makes sense in its routing context. Private address ranges are used inside networks and are not routed globally, while public addresses can be reachable through the public internet subject to routing, firewalls, and service configuration.

Names and addresses are separate

People commonly use domain names while network software communicates with addresses returned through DNS. A single name can resolve to several addresses for redundancy or distribution, and one address can host services for many different names.

Sources and review

MOOR's explanatory text is supported by the following source links.

  1. IANA and IP addressing — IANA
  2. Internet Protocol, Version 6 (IPv6) Specification — RFC Editor

Browse MOOR Knowledge