SNR S2989G-48TX-RPS — преимущества и особенности протокола IPv6 для сетевых технологий [166/553]

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S2989G-24TX Operation Manual

Chapter 3 IP services Configuration

3-4

Moreover, the translation of network data packet addresses baffles the end-to-end

network security check, IPSec authentication header is such an example.

Therefore, in order to solve all kinds of problems existing in IPv4 comprehensively,

the next generation Internet Protocol IPv6 designed by IETF has become the only feasible

solution at present.

First of all, the 128 bits addressing scheme of IPv6 Protocol can guarantee to provide

enough globally unique IP addresses for global IP network nodes in the range of time and

space. Moreover, besides increasing address space, IPv6 also enhanced many other

essential designs of IPv4.

Hierarchical addressing scheme facilitates Route Aggregation, effectively reduces

route table entries and enhances the efficiency and expansibility of routing and data

packet processing.

The header design of IPv6 is more efficient compared with IPv4. It has less data fields

and takes out header checksum, thus expedites the processing speed of basic IPv6

header. In IPv6 header, fragment field can be shown as an optional extended field, so that

data packets fragmentation process won’t be done in router forwarding process, and Path

MTU Discovery Mechanism collaborates with data packet source which enhances the

processing efficiency of router.

Address automatic configuration and plug-and-play is supported. Large amounts of

hosts can find network routers easily by address automatic configuration function of IPv6

while obtaining a globally unique IPv6 address automatically as well which makes the

devices using IPv6 Internet plug-and-play. Automatic address configuration function also

makes the readdressing of existing network easier and more convenient, and it is more

convenient for network operators to manage the transformation from one provider to

another.

Support IPSec. IPSec is optional in IPv4, but required in IPv6 Protocol. IPv6 provides

security extended header, which provides end-to-end security services such as access

control, confidentiality and data integrity, consequently making the implement of

encryption, validation and Virtual Private Network easier.

Enhance the support for Mobile IP and mobile calculating devices. The Mobile IP

Protocol defined in IETF standard makes mobile devices movable without cutting the

existing connection, which is a network function getting more and more important. Unlike

IPv4, the mobility of IPv6 is from embedded automatic configuration to get transmission

address (Care-Of-Address); therefore it doesn’t need Foreign Agent. Furthermore, this

kind of binding process enables Correspondent Node communicate with Mobile Node

directly, thereby avoids the extra system cost caused by triangle routing choice required in

IPv4.

Avoid the use of Network Address Translation. The purpose of the introduction of NAT