[CCNA Routing Switching Exam] Comprehensive IPv6 Video Course
IP version 6 (IPv6) is a new version of the Internet Protocol,
designed as the successor to IP version 4 (IPv4) [RFC-791]. The
changes from IPv4 to IPv6 fall primarily into the following
categories:
o Expanded Addressing Capabilities
IPv6 increases the IP address size from 32 bits to 128 bits, to
support more levels of addressing hierarchy, a much greater
number of addressable nodes, and simpler auto-configuration of
addresses. The scalability of multicast routing is improved by
adding a "scope" field to multicast addresses. And a new type
of address called an "anycast address" is defined, used to send
a packet to any one of a group of nodes.
o Header Format Simplification
Some IPv4 header fields have been dropped or made optional, to
reduce the common-case processing cost of packet handling and
to limit the bandwidth cost of the IPv6 header.
o Improved Support for Extensions and Options
Changes in the way IP header options are encoded allows for
more efficient forwarding, less stringent limits on the length
of options, and greater flexibility for introducing new options
in the future.
o Flow Labeling Capability
A new capability is added to enable the labeling of packets
belonging to particular traffic "flows" for which the sender
requests special handling, such as non-default quality of
service or "real-time" service.
o Authentication and Privacy Capabilities
Extensions to support authentication, data integrity, and
(optional) data confidentiality are specified for IPv6.