What is the difference between IPv4 and IPv6?

Difference between ipv4 and ipv6 is most search term when people come to know IPv6 coming into existence.

IPv4 and IPv6 are the two versions of the Internet protocol currently in use. There are various differences between IPv4 and IPv6 protocols, including their functions, but the key point is the difference in the number of addresses (address spaces) it generates. Below we will specifically introduce the difference between IPv4 and IPv6 protocols.

Difference between IPv4 and IPv6

1, the difference between the protocol address

1), address length

IPv4 protocol has a 32-bit (4 bytes) address length; IPv6 protocol has a 128-bit (16-byte) address length

2), the representation of the address

An IPv4 address is a binary number represented by a decimal. An IPv6 address is a binary number expressed in hexadecimal.

3) Address configuration

The address of the IPv4 protocol can be configured manually or by DHCP.

The IPv4 protocol requires Internet Control Message Protocol version 6 (ICMPv6) or DHCPv6 Stateless Address Autoconfiguration (SLAAC).

2, the difference between the data packets

1), the size of the package

The IPv4 protocol packet requires 576 bytes and the fragmentation is optional. The IPv6 protocol packet needs 1280 bytes and will not be fragmented.

2), Baotou

The header of the IPv4 protocol is 20 bytes long. It does not recognize the packet stream used for QoS processing. It contains a checksum and contains an option field of up to 40 bytes.

The length of the IPv6 protocol header is 40 bytes, including the Flow Label field of the packet flow that specifies the QoS processing, and does not contain the checksum; the IPv6 protocol has no fields, but the IPv6 extension header is available.

3) Packet fragmentation

Packet fragmentation of the IPv4 protocol is done by the forwarding router and the sending host. Packet fragmentation of the IPv6 protocol is only done by the sending host.

3, DNS records

IPv4 protocol address (A) record, mapping host name; pointer (PTR) record, IN-ADDR.ARPA DNS domain.

IPv6 protocol address (AAAA) record, mapping host name; pointer (PTR) record, IP6.ARPA DNS domain

4, IPSec support

IPSec support for IPv4 protocol is only optional. The IPv4 protocol has built-in IPSec support.

5, address resolution protocol

IPv4 Protocol: Address Resolution Protocol (ARP) can be used to map IPv4 addresses to MAC addresses.

IPv6 Protocol: The Address Resolution Protocol (ARP) is replaced by the Neighbor Discovery Protocol (NDP).

6, authentication and encryption

Pv6 provides authentication and encryption, but IPv4 does not.

Summary: The above is the entire content of this article, I hope to be helpful to everyone’s learning.

Compared with IPv4, IPv6 has the following advantages:

IPv6 has a larger address space: the length of the IP address specified in IPv4 is 32, and the maximum number of addresses is 2^32. The length of the IP address in IPv6 is 128, that is, the maximum number of addresses is 2^128. Compared with the 32-bit address space, its address space has increased by 2^128-2^32!

IPv6 uses a smaller routing table: IPv6 address allocation follows the principle of clustering at the beginning, which enables the router to use a record in the routing table to represent a subnet, greatly reducing the length of the routing table in the router, and improving the The speed at which the router forwards packets.

IPv6 adds enhanced multicast support and convection control: this makes the multimedia applications on the network a great opportunity to develop, providing a good network platform for quality of service control.

IPv6 adds support for automatic configuration: This is an improvement and extension of the DHCP protocol, making the management of the network (especially the local area network) more convenient and faster.

IPv6 has higher security: in IPv6 networks, users can encrypt data at the network layer and verify IP packets. The encryption and authentication options in IPv6 provide confidentiality and integrity of packets. The big one enhances the security of the network.

Allow extensions: IPv6 allows protocols to be extended if new technologies or applications require it.
Better header format: IPv6 uses a new header format with options that are separate from the base header and can be inserted between the base header and the upper layer if needed. This simplifies and speeds up the routing process because most of the options do not need to be routed.

New option: IPv6 has some new options for implementing additional features.

The above is the details of the difference between IPv4 and IPv6, please pay attention to other related articles on network!