Ipv6 Addresses - HP FlexNetwork MSR2003 Configuration Manual

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Stateless address autoconfiguration enables a host to automatically generate an IPv6 address
and other configuration information by using its link-layer address and the prefix information
advertised by a router.
To communicate with other hosts on the same link, a host automatically generates a link-local
address based on its link-layer address and the link-local address prefix (FE80::/10).
Built-in security
IPv6 defines extension headers to support IPsec. IPsec provides end-to-end security and enhances
interoperability among different IPv6 applications.
QoS support
The Flow Label field in the IPv6 header allows the device to label the packets of a specific flow for
special handling.
Enhanced neighbor discovery mechanism
The IPv6 neighbor discovery protocol uses a group of ICMPv6 messages to manage information
exchange among neighboring nodes on the same link. The group of ICMPv6 messages replaces
ARP messages, ICMPv4 router discovery messages, and ICMPv4 redirect messages and provides
a series of other functions.
Flexible extension headers
IPv6 eliminates the Options field in the header and introduces optional extension headers to provide
scalability and improve efficiency. The Options field in the IPv4 packet header contains a maximum
of 40 bytes, whereas the IPv6 extension headers are restricted to the maximum size of IPv6 packets.

IPv6 addresses

IPv6 address formats
An IPv6 address is represented as a set of 16-bit hexadecimals separated by colons (:). An IPv6
address is divided into eight groups, and each 16-bit group is represented by four hexadecimal
numbers, for example, 2001:0000:130F:0000:0000:09C0:876A:130B.
To simplify the representation of IPv6 addresses, you can handle zeros in IPv6 addresses by using
the following methods:
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The leading zeros in each group can be removed. For example, the above address can be
represented in a shorter format as 2001:0:130F:0:0:9C0:876A:130B.
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If an IPv6 address contains one or more consecutive groups of zeros, they can be replaced by
a double colon (::). For example, the above address can be represented in the shortest format
as 2001:0:130F::9C0:876A:130B.
IMPORTANT:
A double colon can appear once or not at all in an IPv6 address. This limit allows the device to
determine how many zeros the double colon represents and correctly convert it to zeros to
restore a 128-bit IPv6 address.
An IPv6 address consists of an address prefix and an interface ID, which are equivalent to the
network ID and the host ID of an IPv4 address.
An IPv6 address prefix is written in IPv6-address/prefix-length notation. The prefix-length is a
decimal number indicating how many leftmost bits of the IPv6 address are in the address prefix.
IPv6 address types
IPv6 addresses include the following types:
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Unicast address—An identifier for a single interface, similar to an IPv4 unicast address. A
packet sent to a unicast address is delivered to the interface identified by that address.
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