Quanta Cloud Technology QuantaMesh QNOS5, Configuration Manual

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Translation (NAT), which is used in IPv4 networks to reduce the number of globally unique IP addresses
required for a given network.
In the QNOS software, IPv6 coexists with IPv4. As with IPv4, IPv6 routing can be enabled on loopback and VLAN
interfaces. Each L3 routing interface can be used for IPv4, IPv6, or both. IP protocols running over L3 (for
example, UDP and TCP) are common to both IPv4 and IPv6.
7.6.1. How Does IPv6 Compare with IPv6
There are many conceptual similarities between IPv4 and IPv6 network operation. Addresses still have a
network prefix portion (network) and a device interface specific portion (host). While the length of the
network portion is still variable, most users have standardized on using a network prefix length of 64 bits. This
leaves 64 bits for the interface specific portion, called an Interface ID in IPv6. Depending upon the
underlying link addressing, the Interface ID can be automatically computed from the link (e.g., MAC
address). Such an automatically computed Interface ID is called an EUI-64 identifier, which is the interface
MAC address with ff:fe inserted in the middle.
IPv6 packets on the network are of an entirely different format than traditional IPv4 packets and are also
encapsulated in a different EtherType (86DD rather than 0800 which is used with IPv4). The details for
encapsulating IPv6 in Ethernet frames are described in RFC4862.
Unlike IPv4, IPv6 does not have broadcasts. There are two types of IPv6 addresses — unicast and multicast.
Unicast addresses allow direct one-to-one communication between two hosts, whereas multicast addresses
allow one-to-many communication. Multicast addresses are used as destinations only. Unicast addresses
will have 00 through fe in the most significant octets and multicast addresses will have ff in the most
significant octets.
7.6.2. How are IPv6 Interface Configured
In the QNOS software, IPv6 coexists with IPv4. As with IPv4, IPv6 routing can be enabled on VLAN interfaces.
Each L3 routing interface can be used for IPv4, IPv6, or both simultaneously.
Neighbor Discovery (ND) protocol is the IPv6 replacement for Address Resolution Protocol (ARP) in IPv4. The
IPv6 Neighbor Discovery protocol is described in detail in RFC4861. Router advertisement is part of the
Neighbor Discovery process and is required for IPv6. As part of router advertisement, PowerConnect 7000
Series switch software supports stateless auto configuration of end nodes. The switch supports both EUI-64
interface identifiers and manually configured interface IDs.
While optional in IPv4, router advertisement is mandatory in IPv6. Router advertisements specify the
network prefix(es) on a link which can be used by receiving hosts, in conjunction with an EUI-64 identifier, to
autoconfigure a host’s address. Routers have their network prefixes configured and may use EUI-64 or
manually configured interface IDs. In addition to zero or more global addresses, each IPv6 interface also has
an autoconfigured “link-local” address which is:

fe80::/10, with the EUI-64 address in the least significant bits.

Reachable only on the local VLAN — link-local addresses are never routed.

Not globally unique