IPv6

IPv6 is the 128-bit network addressing protocol, written in colon-separated hexadecimal (e.g., 2001:db8::1), offering about 3.4×10^38 addresses to solve IPv4 exhaustion.

Purpose

It provides ample address space for IoT and mobile devices while improving on IPv4's security and efficiency.

Mechanism

The 128 bits appear as eight 16-bit hexadecimal groups; a run of zero groups can be compressed to :: (once only). It supports SLAAC stateless autoconfiguration, link-local (fe80::/10), and unique-local (fd00::/8) addresses. The header is simplified, with extension headers chained after it.

Use cases

Modern cloud and mobile networks
Addressing massive IoT fleets
IPv4 replacement deployments
Dual-stack and tunneling

Examples

Input

2001:db8:85a3::8a2e:370:7334

Output

A public IPv6 address

:: compressing zeros

Common errors

IPv6 and IPv4 are not interoperable without dual-stack or NAT64: Deploy dual-stack or DNS64+NAT64

Related terms

IPv4 is the 32-bit network addressing protocol, written in dotted decimal (e.g., 192.168.1.1), with roughly 4.3 billion addresses—now exhausted.

An IP address is the numeric identifier assigned to a network interface—32 bits for IPv4 (four decimal octets) and 128 bits for IPv6 (eight hexadecimal groups)—used for network addressing.

A subnet is a technique for dividing a large network into smaller ones, using the subnet mask to separate the network number from the host number, improving address utilization and isolation.

CIDR (Classless Inter-Domain Routing) expresses a network as IP/prefix length (e.g., 10.0.0.0/8), replacing IPv4 address classes with flexible network partitioning.

Related tools

IP Address Info

Analyze IPv4/IPv6 addresses and CIDR subnets: class, private/multicast flags, binary/hex, reverse DNS, network/broadcast/hosts. Free, private, and 100% client-side.

References