Additional IPv6 Features

Although IPv6 appears to have functionality similar to CIDRs, there are

many additional features that were not included in IPv4. These features

make IPv6 much more robust and convenient. These changes include a

streamlined IPv6 header, stateless configuration, built in security, bet 

ter QoS, and increased real time performance.

Streamlined IPv6 Header

The IPv6 header has a new format that is designed to keep header over 

head to a minimum. This format is achieved by moving both nonessen 

tial fields and option fields to extension headers that are placed after

the IPv6 header. The streamlined IPv6 header provides more efficient

processing at intermediate routers.

Stateless and Stateful Configuration

IPv6 supports both stateful and stateless address configurations. IPv6

will work with or without a DHCP server. With stateless address config 

uration, hosts on a link automatically configure themselves with IPv6

addresses for the link (called link local addresses) and with addresses

derived from prefixes advertised by local routers. Even in the absence of

a router, hosts on the same link can automatically configure themselves

with link local addresses and communicate without manual configura 

tion.

Built in Security

Support for IPSec is an IPv6 protocol suite requirement. This require 

ment provides a standards based solution for network security and pro 

motes interoperability between different IPv6 implementations.

Better Support for QoS

New fields in the IPv6 header define how traffic is handled and identi 

fied. Traffic identification using a flow label field in the IPv6 header

allows routers to identify and provide special handling for packets

belonging to a flow, which is a series of packets between a source and

destination. Because the traffic is identified in the IPv6 header, support

for QoS can be achieved even when the packet payload is encrypted

through IPSec.

Real Time Performance

IPv6 offers a packet prioritization feature that provides the real time

and near real time applications an improved response time. Conse 

quently, IPv6 will become the protocol of choice for those applications.

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