Filter
Top Products
DES-7200 Configuration Guide Chapter 2 IPv6 Configuration
2-1
2 IPv6 Configuration
2.1 IPv6 Overview
As the Internet is growing rapidly and the IPv4 address space is exhausting, the
limitation of the IPv4 is more obvious. The research and practice of the next generation
of the Internet Protocol becomes popular. Furthermore, the IPng workgroup of the
IETF determines the protocol specification of IPng referred to as IPv6. Refer to
RFC2460 for details.
Key Features of Ipv6:
z More Address Space
The length of address will be extended to 128 bits from the 32 bits of Ipv4. Namely,
there are 2^128-1 addresses for IPv6. The IPv6 adopts the hierarchical address mode
and supports multiple-level IP address assignment, for example, from the Internet
backbone network to the internal subnet of enterprises.
z Simplified Format of Packet Header
The design principle of new IPv6 packet header is to minimize the overhead. For this
reason, some non-critical fields and optional fields are removed from the packet
header and placed into the extended packet header. The length of the IPv6 address is
4 times of IPv4 address; its packet header is only 2 times of IPv4 header. The
improved IPv6 packet header is more efficient for forwarding, for instance, there is no
checksum in the IPv6 packet header and it is not necessary for the IPv6 router to
process the fragment during forwarding (the fragment is completed by the originator).
z High-efficient hierarchical Addressing and Routing Structure
The IPv6 adopts the aggregation mechanism and defines flexible hierarchical
addressing and routing structure, and several networks at the same level is presented
as a unified network prefix at the higher level of routers. So it obviously reduces the
entries that the router must maintain and greatly minimizes the routing and storage
overhead.
z Simple Management: Plug and Play
Simplify the management and maintenance of the network node by the implementation
of a series of auto-discovery and auto-configuration functions. Such as the Neighbor
Discovery, the MTU Discovery, the Router Advertisement, the Router Solicitation and