Major Features of IPv6
The defining feature of IPv6 is increased address space in comparison to IPv4.
IPv6 also improves Internet capabilities in numerous areas, as outlined in this section.
IP address size increases from 32 bits in IPv4 to 128 bits
in IPv6, to support more levels of addressing hierarchy. In addition, IPv6 provides many
more addressable IPv6 systems. For more information, see IPv6 Addressing Overview.
Address Autoconfiguration and Neighbor Discovery
The IPv6 Neighbor Discovery (ND) protocol facilitates the autoconfiguration of IPv6 addresses. Autoconfiguration is the ability
of an IPv6 host to automatically generate its own IPv6 address, which makes
address administration easier and less time-consuming. For more information, see IPv6 Address Autoconfiguration.
The Neighbor Discovery protocol corresponds to a combination of these IPv4 protocols: Address
Resolution Protocol (ARP), Internet Control Message Protocol (ICMP), Router Discovery (RDISC), and ICMP
Redirect. IPv6 routers use Neighbor Discovery to advertise the IPv6 site prefix. IPv6
hosts use Neighbor Discovery for various purposes, which include soliciting the prefix from an
IPv6 router. For more information, see IPv6 Neighbor Discovery Protocol Overview.
Header Format Simplification
The IPv6 header format either drops or makes optional certain IPv4 header fields.
This change keeps the bandwidth cost of the IPv6 header as low
as possible, despite the increased address size. Even though IPv6 addresses are four times
longer than IPv4 addresses, the IPv6 header is only twice the size of
the IPv4 header.
Improved Support for IP Header Options
Changes in the way IP header options are encoded allow for more
efficient forwarding. Also, IPv6 options have less stringent limits on their length. The changes
provide greater flexibility for introducing new options in the future.
Application Support for IPv6 Addressing
Many critical Solaris network services recognize and support IPv6 addresses, for example:
Name services, such as DNS, LDAP, and NIS. For more information on IPv6 support by these name services, see System Administration Guide: Naming and Directory Services (DNS, NIS, and LDAP).
Authentication and privacy applications, such as IP Security Architecture (IPsec) and Internet Key Exchange (IKE). For more information, see Part III, IP Security.
Differentiated services, as provided by IP Quality of Service (IPQoS). For more information, see Part VI, IP Quality of Service (IPQoS).
Failover detection, as provided by IP network multipathing (IPMP). For more information, see Part V, IPMP.
Additional IPv6 Resources
In addition to this Part, you can obtain information about IPv6 from the
sources that are listed in the following sections.
IPv6 Requests for Comments and Internet Drafts
Many RFCs are available regarding IPv6. The following table lists the major IPv6
articles and their Internet Engineering Task Force (IETF) web locations as of this
Table 3-1 IPv6–Related RFCs and Internet Drafts
The following web sites provide useful information about IPv6.
Table 3-2 IPv6–Related Web Sites
IPv6–related presentations, events, classes, and implementations worldwide are available from this society's web
Internet Educational Task Force IPv6 Working Group
Links to all relevant IPv6 RFCs
and Internet Drafts are on the home page of this IETF working group
UK IPv6 Resource Center
Materials and links that are related to the 6bone, the
international test IPv6 network, and University of Lancaster IPv6 projects are on this
web site of University of Lancaster UK