Why is IPv6 preferred over IPv4?

The Internet Protocol, or IP, is a set of rules that allows our computers and other communication devices to communicate via the Internet. When you open a website on your browser, a data packet including your IP address is transmitted to the web server's IP address, and the website is then served back to your device over the Internet.

IP addresses function similarly as street addresses on a map do. They are in charge of directing packets to their correct destinations. IP controls all Internet traffic. Data packets containing the IP addresses of their points of origin and destinations travel on the Internet, with routers guiding them down the correct path.


IPv4 (Internet Technology Version 4) is the fourth iteration of the Internet Protocol and a widely used data transfer protocol over various networks.

  • In packet-switched layer networks, such as Ethernet, IPv4 is a connectionless protocol. It allows each network device to be identified, establishing a connection.

  • Depending on the network type, there are various ways to configure IPv4 with multiple devices, including manual and automatic configurations.

  • IPv4 uses the best-effort model. This model does not ensure delivery or avoid duplicate delivery; these concerns are handled by upper-layer transport. It's utilized in the OSI model's packet-switched connection layer.

  • For Ethernet communication, IPv4 uses five classes of 32-bit addresses − A, B, C, D, and E. The bit length for addressing the network host differs between Classes A, B, and C. Multicasting is reserved for class D addresses, whereas future use is reserved for class E addresses. IPv4 has a limit of 232 host addresses it can allocate to end-users.


The Internet Engineering Task Force (IETF), the open standards body in charge of creating technical Internet protocols, became aware of a potential vulnerability in IPv4 as the use of the Internet grew in the 1990s. The number of IP addresses it can create is restricted, and it will not be enough to give to Internet-connected devices shortly.

An improved standard for future-proof IP addressing was agreed upon by the Internet Engineering Task Force (IETF). By 1998, it had developed a draught standard for IPv6, a better and upgraded version of IPv4 that was intended to replace IPv4 eventually.

  • A 128-bit IP address is provided via IPv6. This means, it can generate 2128 or roughly 3.4☓1038 addresses. The amount of IPv6 addresses can reach trillions of trillions in layman's terms.

  • Because IPv6 also reserves blocks of numbers for particular purposes or prohibits using specific numbers entirely, the total number of IPv6 addresses should be slightly less. Nonetheless, the amount of IPv6 addresses is almost endless, so future demand should be met.

  • The same design principles apply to IPv6 addresses, which are divided into eight groups of four hexadecimal digits separated by colons. Most IPv6 addresses do not use all of their 128 bits, resulting in fields that are either entirely zeros or are padded with zeros.

  • The two colons (::) can represent a contiguous 16-bit field of zeros in IPv6 addressing scheme.

Difference between IPv4 and IPv6

The following table highlights the major differences between IPv4 and IPv6 −

IPv4 addresses are 32 bits long, consisting of four octets, each eight bits long.IPv6 addresses are 128 bits long, consisting of 8 fields or octets, each 16 bits long.
IPv4 does not support encryption or authentication.IPv6 includes encryption and authentication.
IPv4 addresses are four octets long and written in decimal format.IPv6 is made up of eight fields, each with two octets. As a result, IPv6 has 16 octets in total. In this case, the address is written in hexadecimal.
The broadcast information transfer mechanism of IPv4 is used.IPv6 uses a multicasting transmission technique, ensuring that network services are delivered quickly.
Checksum fields are present in IPv4.Checksum fields are not included in IPv6.
In IPv4, end-to-end connection integrity is unattainable.IPv6 allows for end-to-end connection integrity.
DHCP and manual address settings are both supported by IPv4.DHCP, manual, auto-configuration, and renumbering are all supported in IPv6.