Despite the fact that IPv6 was developed in 1996, and the need to replace IPv4 with it was quite obvious even back in that year, the transition is still in place. During the first decades after its development, the older version completely dominated the Internet. As a result, by 2013, IPv6 usage was no more than 1%. However, IPv4 keeps depleting its resources more and more, and in the meantime, the share of IPv6 on the Internet exceeds 25% as of today.
Due to the slow spread of the newer protocol in the structure of the Internet, the advantages and differences of IPv6 are known for very few people. This leads to misunderstandings and a large number of questions among Internet users. In this article, we are going to try to answer common questions about IPv6 and its differences from the previous version.
The Internet Protocol. What is it?
IP (short for Internet Protocol) is one of the protocols of the TCP/IP network model, and one of the first and most important components of this stack. IP refers to the network layer of OSI model. It is one of the fundamental elements that ensure the operation of the Internet.
The structure of the TCP/IP stack is shown in the table below.
The layer of the network model
HTTP, SMTP, DNS, SSH, FTP
IPv4,IPv6, Ipsec, OSPF, NAT
Channel (the layer of access to the network)
Ethernet, IEEE, PPP
Network layer protocols, where IP is the most important one, route the transmitted data. IP is the pathfinder for date on the Internet
The operation of the Internet protocol and its interaction with protocols of the other layers is based on the following mechanism. To send data from higher layers of OSI model to lower ones, the data need to be divided into pieces or IP-fragments.
Each IP fragment has a header containing meta information, which includes
- Payload length – the length of data in octets, excluding the header.
- Traffic class – priority of data when transmitting over the Network.
- The protocol version: IPv4 or IPv6.
- Recipient's IP address
- Sender's IP address
- Time to live – the number of routers that a packet can pass through.
Format of the header and composition of its parameters depend on version of the protocol in use: IPv4 or IPv6. We will tell you more about their differences below.
After transmission to the destination, the packet is only analyzed for header integrity at the network layer. In this case, the package with an undamaged header is passed to the upper layers, and if there is damage, the package is deleted. The integrity of information in packets is not monitored at the IP layer. Instead, this operation is performed at the transport layer via the Transmission Control Protocol or better known as TCP.
Using the Internet Protocol for data transfer has several advantages. First of all, it can be used to achieve higher bandwidth of the data channel, this is possible due to the fact that each packet is sent to the destination in different ways, if necessary. Due to this, there are no bottlenecks in the system, and the load is distributed evenly across the channels. At the same time, the technology works well in networks with different numbers of routers, and responds painlessly to changes in their number and the structure of connections between them.
A small disadvantage of IP may be the significant size of the headers, which plays a role when a large amount of data is transmitted. However, this can be corrected by using an additional protocol in conjunction with IP that converts headers to a more compact form.
In general, the Internet is functioning successfully on its protocol, and it doesn't look like there will be a need to switch to another inter-network communication technology in the near future.
What is the difference between IPv6 and IPv4?
Most of the Internet still operates on the IPv4, but a more modern IPv6 is increasing its presence every year. What is the difference between them, and why is it necessary to switch to the modern version 6?
The main reason lies in the way the host address is represented in the network. In IPv4, the user's address is specified by four numbers from 0 to 255, separated by a dot. Each number carries 8 bits (1 byte) of information. Thus, the length of the IPv4 address is 32 bits or 4 bytes. Version 4 allows you to get about 4.3 billion addresses.
The number of devices connected to the Internet is constantly growing. Therefore, it is necessary to look for a replacement for IPv4.
IPv6 was developed to replace IPv4. The main difference from its predecessor is in the format of addresses. The IPv6 address consists of eight numbers separated by a colon. In this case, each of the numbers carries 2 bytes or 16 bits of information, because of the hexadecimal number system. Thus, the address length of IPv6 is 128 bits. And the number of possible unique addresses compared to IPv4 is immense.
Expanding the address space is the main reason for switching to the newer version of the protocol. The developers also made some changes of the protocol structure itself.
Changes affected IP headers: even though they became longer, IPv6 managed to revise their structure and reduce the number of transmitted parameters and fields. As a result, IPv6 provides more efficient packet routing on the Internet.
With IPv6, address space saving is no longer the issue. Now it is more logical and intuitive to organize the structure of subnets. So you can make subnets based on the subnet ID or interface ID.
How do I access IPv6?
The transition to IPv6 is gradual, but it will replace IPv4 completely. But how can one upgrade to the newer version faster and what benefits will this give the user?
The pros of IPv6 described earlier in most cases allow you to increase the speed of your Internet connection if your web applications support IPv6 addresses. Moreover, all major web resources already support the newer version.
To start using the newer version of the protocol you can use one of three common methods:
- Choose ISP that supports IPv6
- Register your own subnet
- Use the tunnel broker service
After a while, Internet service providers will start actively distributing IPv6 to their clients, and most websites will support the protocol. But you can switch to it right now if you feel the need or just want to try a more modern technology faster.