> # Information About IPV6

> IP version 6 (IPv6) provides extended addressing capability beyond those provided in IP version 4 (IPv4) in Cisco MDS NX-OS by quadrupling the number of network address bits from 32 bits (in IPv4) to 128 bits. The architecture of IPv6 has been designed to allow existing IPv4 users to transition easily to IPv6 while providing services such as end-to-end security, quality of service (QoS), and globally unique addresses.

> IPv6 provides the following enhancements over IPv4:

> - Allows networks to scale and provide global reachability.
> - Reduces the need for private address and network address translation (NAT).
> - Provides simpler autoconfiguration of addresses.

> This section describes the IPv6 features supported by Cisco MDS NX-OS and includes the following topics:

> - Extended IPv6 Address Space for Unique Addresses
> - IPv6 Address Formats
> - IPv6 Address Prefix Format
> - IPv6 Address Type: Unicast
> - IPv6 Address Type: Multicast
> - ICMP for IPv6
> - Path MTU Discovery for IPv6
> - IPv6 Neighbor Discovery
> - Router Discovery
> - IPv6 Stateless Autoconfiguration
> - Dual IPv4 and IPv6 Protocol Stacks
> - IPv6 Addressing and Enabling IPv6 Routing
> - Transitioning from IPv4 to IPv6

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