Definition of IPv4 vs IPv6

IPv4, InternetProtocolversion4, is one of the most widely used protocols in the Internet. It uses 32-bit addresses expressed in dotted decimal, such as 192.168.1.1.

IPv6,  namely  InternetProtocolversion6  (InternetProtocolversion6),  is  in  order to  solve the  IPv4 address exhaustion and other problems and the development of a new generation of protocol. Its address length of 128 bits, usually expressed as a hexadecimal number 8 group, middle colon space, for example: 2001 0 db8:85 a3:0000-0000:8 a2e: 0370-7334.

The main differences between IPv4 and IPv6

Address Space:

IPv4:  IPv4  uses  a  32-bit  address  length  and  can  provide  approximately  4.3   billion   unique addresses. Due to the explosive growth of Internet devices, IPv4 addresses have gradually dried up.

IPv6: Using a 128-bit address length, IPv6 can theoretically provide 3.4×10^38 addresses, which can allocate a  unique  address to almost every grain  of sand. This solves the  problem  of  IPv4 address exhaustion.

Addresses represent:

IPv4: IPv4 addresses are usually represented in dotted decimal, such as 192.168.1.1.

IPv6: IPv6 address use a colon separated eight groups of hexadecimal representation, such as: 2001 0 db8:85 a3:0000-0000:8 a2e: 0370-7334. To simplify the presentation, consecutive zeros can be omitted as double colons (::), such as 2001:db8::8a2e:370:7334.

Head complexity:

IPv4: The header of IPv4 is relatively simple, containing a small number of required fields, and the header length is 20-60 bytes.

IPv6: The IPv6 header is more complex, but more efficient, with a fixed header length of 40 bytes, removing unnecessary fields, and adding an expansion header.

Address assignment:

IPv4:  IPv4  addresses  are  assigned  using  the  classification  (Class  A,  B,  C,  D,  E)  and  CIDR (unclassified Inter-domain routing) methods.

IPv6:  IPv6  uses classless address assignment, which simplifies address management and  route aggregation and improves network efficiency.

Security:

IPv4: IPv4 has no built-in security mechanisms and relies on external protocols (such as IPSec) for secure communication.

IPv6: IPSec protocol is built into IPv6, which provides end-to-end encryption and authentication mechanisms to enhance network security.

Auto-configuration:

IPv4: IPv4 supports DHCP protocol for address auto-configuration.

IPv6:  IPv6  supports  Stateless  Address  auto-configuration  (SLAAC)  and  DHCPv6,  which  is  more flexible and efficient.