Introduction to IPv6 addressing and routing Methods

The exact number of addresses contained in the 128-bit address space is 340,282,366,920,938,463,463,374,607,431,768,211,456. These spaces are sufficient to provide an independent IP address for each grain of sand on the earth.

At the same time, IPv6 can automatically configure different types of addresses for host interfaces:

Global Address (Globally)

Global unicast address (unicast)

Region address (on-site)

Link local address)

Local address)

Broadcast address (Broadcast)

Multicast group address)

Anycast address)

Mobile Address (Mobility)

Home address)

Care-of address)

Aggregatableglobal unicast is the default IPv6 address. This address type is based on a layered network topology. The underlying layer of the layered network topology is the Internet service provider (ISP), which is based on the customer network and its subnet. The 128-bit address is divided into two parts: prefix and suffix, each of which is 64-bit. The 64-bit suffix address is determined by the device interface.

IPv6 hosts do not need to understand the hierarchical structure of such addresses, so it has great benefits for network security. To ensure the security of communication with the external internet, the company's workstation can use a designated address. When you need to securely transmit route topology information between adjacent routers, you can also use a local connection address. Multicast addresses also belong to this hierarchical address structure and are used for automatic address configuration.

In addition, this address structure also supports some new services, such as optimized IP layer mobile or broadcast services. On IPv6 Internet networks, these services can be implemented globally from the very beginning. IPv4 has almost no such flexibility. This hierarchical address structure of IPv6 also enables routers to use multiple clustering short route tables, each of which stores a certain number of records. One feature of IPv4 is that the content of the route table increases exponentially, increasing the processing latency of each packet. In IPv6, such processing latency is no longer a limiting factor.

IPv6 also improves the basic Header Format of the IP packet. This simplified package structure is a major improvement for IPv4, which helps to compensate for the bandwidth occupied by IPv6 long addresses. IPv6 16-byte address length is four times the IPv4 4-byte address length, but the total length of IPv6 Header is only two times the total length of IPv4 header. There are few fields in the IPv6 Header, And the header length is fixed. These features simplify the hardware implementation of vrouters. Unlike IPv4, IPv6 does not divide data packets during the routing process, which further reduces the routing load. These improvements enable IPv6 to adapt to exponential growth of Internet traffic within a reasonable overhead range.

Another advantage of IPv6 is that it can be placed behind the basic header when needed. This also improves the routing capability. Unlike the Skip header, this continuous header is analyzed on the terminal node. An instance is an IP Security header (IPSec), which can improve end-to-end security. Other Extended Headers include Routing headers, breaking headers, authentication headers, and sink headers.

1. IPv6 Protocol address type
2. IPv6 technology and application prospects