As the Internet of Things (IoT) continues to grow exponentially, more devices connect online daily. There has been fear that, at some point, addresses would just run out. This conjecture is starting to come true.

Have no fear; the Internet is not coming to an end. There is a solution to the problem of diminishing IPv4 addresses. We will provide information on how more addresses can be created, and outline the main issues that need to be tackled to keep up with the growth of IoT by adopting IPv6.

We also examine how Internet Protocol version 6 (IPv6) vs. Internet Protocol 4 (IPv4) plays an important role in the Internet’s future and evolution, and how the newer version of the IP is superior to older IPv4.

How an IP Address Works

IP stands for “Internet Protocol,” referring to a set of rules which govern how data packets are transmitted across the Internet.

Information online or traffic flows across networks using unique addresses. Every device connected to the Internet or computer network gets a numerical label assigned to it, an IP address that is used to identify it as a destination for communication.

Your IP identifies your device on a particular network. It’s I.D. in a technical format for networks that combine IP with a TCP (Transmission Control Protocol) and enables virtual connections between a source and destination. Without a unique IP address, your device couldn’t attempt communication.

ipv4 vs ipv6 adoption

IP addresses standardize the way different machines interact with each other. They trade data packets, which refer to encapsulated bits of data that play a crucial part in loading webpages, emails, instant messaging, and other applications which involve data transfer.

Several components allow traffic to flow across the Internet. At the point of origin, data is packaged into an envelope when the traffic starts. This process is referred to as a “datagram.” It is a packet of data and part of the Internet Protocol or IP.

A full network stack is required to transport data across the Internet. The IP is just one part of that stack. The stack can be broken down into four layers, with the Application component at the top and the Datalink at the bottom.


  • Application – HTTP, FTP, POP3, SMTP
  • Transport – TCP, UDP
  • Networking – IP, ICMP
  • Datalink – Ethernet, ARP

As a user of the Internet, you’re probably quite familiar with the application layer. It’s one that you interact with daily. Anytime you want to visit a website; you type in http://[web address], which is the Application.

Are you using an email application? At some point then, you would have set up an email account in that application, and likely came across POP3 or SMTP during the configuration process. POP3 stands for Post Office Protocol 3 and is a standard method of receiving an email. It collects and retains email for you until picked up.

From the above stack, you can see that the IP is part of the networking layer. IPs came into existence back in 1982 as part of ARPANET. IPv1 through IPv3 were experimental versions. IPv4 is the first version of IP used publicly, the world over.

IPv4 Explained

IPv4 or Internet Protocol Version 4 is a widely used protocol in data communication over several kinds of networks. It is the fourth revision of the Internet protocol. It was developed as a connectionless protocol for using in packet-switched layer networks like Ethernet. Its primary responsibility is to provide logical connections between network devices, which includes providing identification for every device.

IPv4 is based on the best-effort model, which guarantees neither delivery nor avoidance of a duplicate delivery and is hired by the upper layer transport protocol, such as the Transmission Control Protocol (TCP). IPv4 is flexible and can automatically or manually be configured with a range of different devices depending on the type of network.

Technology Behind IPv4

IPv4 is both specified and defined in the Internet Engineering Task Force’s (IETF) publication RFC 791, used in the packet-switched link layer in OSI models. It uses a total of five classes of 32-bit addresses for Ethernet communication: A, B, C, D, and E. Of these, classes A, B, and C have a different bit length for dealing with network hosts, while Class D is used for multi-casting. The remaining Class E is reserved for future use.

Subnet Mask of Class A – or /8

Subnet Mask of Class B – or /16

Subnet Mask of Class C – or /24

Example: The Network with a /16 subnet mask can use addresses ranging from to It’s important to note that the address is reserved only for broadcasting within the users. Here, the IPv4 can assign host addresses to a maximum of 232 end users.

IP addresses follow a standard, decimal notation format:

The above number is a unique 32-bit logical address. This setup means there can be up to 4.3 billion unique addresses. Each of the four groups of numbers are 8 bits. Every 8 bits are called an octet. Each number can range from 0 to 255. At 0, all bits are set to 0. At 255, all bits are set to 1. The binary form of the above IP address is 10101011.00011110.00000010.00000101.

Even with 4.3 billion possible addresses, that’s not nearly enough to accommodate all of the currently connected devices. Device types are far more than just desktops. Now there are smartphones, hotspots, IoT, smart speakers, cameras, etc. The list keeps proliferating as technology progresses, and in turn, so do the number of devices.

the past and future of ipv4 and ipv6

Future of IPv4

IPv4 addresses are set to finally run out, making IPv6 deployment the only viable solution left for the long-term growth of the Internet. I

n October 2019, RIPE NCC, one of five Regional Internet Registries, which is responsible for assigning IP addresses to Internet Service Providers (ISPs) in over 80 nations, announced that only one million IPv4 addresses were left. Due to these limitations, IPv6 has been introduced as a standardized solution offering a 128-bit address length that can define up to 2128 nodes.

Recovered addresses will only be assigned via a waiting list. And that means only a couple hundred thousand addresses can be allotted per year, which is not nearly enough to cover the several million that global networks require today. The consequences are that network tools will be forced to rely on expensive and complicated solutions to work around the problem of fewer available addresses. The countdown to zero addresses means enterprises world-wide have to take stock of IP resources, find interim solutions, and prepare for IPv6 deployment, to overcome the inevitable outage.

In the interim, one popular solution to bridge over to IPv6 deployment is Carrier Grade Network Address Translation (CGNAT). This technology allows for the prolongated use of IPv4 addresses. It does so by allowing a single IP address to be distributed across thousands of devices. It only plugs the hole in the meantime as CGNAT cannot scale indefinitely. Every added device creates another layer on NAT, that increases its workload and complexity, and thereby raises the chances of a CGNAT failing. When this happens, thousands of users are impacted and cannot be quickly put back online.

One more commonly-used workaround is IPv4 address trading. This is a market for selling and buying IPv4 addresses that are no longer needed or used. It’s a risky play since prices are dictated by supply and demand, and it can become a complicated and expensive process to maintain the status quo.

IPv4 scarcity remains a massive concern for network operators. The Internet won’t break, but it is at a breaking point since networks will only find it harder and harder to scale infrastructure for growth. IPv4 exhaustion goes back to 2012 when the Internet Assigned Numbers Authority (IANA) allotted the last IPv4 addresses to RIPE NCC. The long-anticipated run-out has been planned for by the technical community, and that’s where IPv6 comes in.

How Is IPv6 Different?

Internet Protocol Version 6 or IPv6 is the newest version of Internet Protocol used for carrying data in packets from one source to a destination via various networks. IPv6 is considered as an enhanced version of the older IPv4 protocol, as it supports a significantly larger number of nodes than the latter.

IPv6 allows up to 2128 possible combinations of nodes or addresses. It is also referred to as the Internet Protocol Next Generation or IPng. It was first developed in the hexadecimal format, containing eight octets to provide more substantial scalability. Released on June 6, 2012, it was also designed to deal with address broadcasting without including broadcast addresses in any class, the same as its predecessor.

comparing difference between ipv4 and ipv6

Comparing Difference Between IPv4 and IPv6

Now that you know more about IPv4 and IPv6 in detail, we can summarize the differences between these two protocols in a table. Each has its deficits and benefits to offer.

Points of Difference IPV4 IPV6
Compatibility with Mobile Devices Addresses use of dot-decimal notations, which make it less suitable for mobile networks. Addresses use hexadecimal colon-separated notations, which make it better suited to handle mobile networks.
Mapping Address Resolution Protocol is used to map to MAC addresses. Neighbor Discovery Protocol is used to map to MAC Address.
Dynamic Host Configuration Server When connecting to a network, clients are required to approach Dynamic Host Configuration Servers. Clients are given permanent addresses and are not required to contact any particular server.
Internet Protocol Security It is optional. It is mandatory.
Optional Fields Present Absent. Extension headers are available instead.
Local Subnet Group Management Uses Internet Group Management Protocol or GMP. Uses Multicast Listener Discovery or MLD.
IP to MAC resolution For Broadcasting ARP. For Multicast Neighbor Solicitation.
Address Configuration It is done manually or via DHCP. It uses stateless address autoconfiguration using the Internet Control Message Protocol or DHCP6.
DNS Records Records are in Address (A). Records are in Address (AAAA).
Packet Header Packet flow for QoS handling is not identified. This includes checksum options. Flow Label Fields specify packet flow for QoS handling.
Packet Fragmentation            Packet Fragmentation is allowed from routers when sending to hosts. For sending to hosts only.
Packet Size The minimum packet size is 576 bytes. Minimum packet size 1208 bytes.
Security It depends mostly on Applications. Has its own Security protocol called IPSec.
Mobility and Interoperability Network topologies are relatively constrained, which restricts mobility and interoperability. IPv6 provides mobility and interoperability capabilities which are embedded in network devices
SNMP Support included. Not supported.
Address Mask It is used for the designated network from the host portion. Not Used
Address Features Network Address Translation is used, which allows a single NAT address to mask thousands of non-routable addresses. Direct Addressing is possible because of the vast address space.
Configuration the Network Networks are configured either manually or with DHCP. It has autoconfiguration capabilities.
Routing Information Protocol Supports RIP routing protocol. IPv6 does not support RIP routing protocol.
Fragmentation It’s done by forwarding and sending routes. It is done only by the sender.
Virtual Length Subnet Mask Support Supports added. Support not added.
Configuration To communicate with other systems, a newly installed system must be configured first. Configuration is optional.
Number of Classes Five Different Classes, from A to E. It allows an unlimited number of IP Addresses to be stored.
Type of Addresses Multicast, Broadcast, and Unicast Anycast, Unicast, and Multicast
Checksum Fields Has checksum fields, example: Not present
Length of Header Filed 20 40
Number of Header fields 12 8
Address Method It is a numeric address. It is an alphanumeric address.
Size of Address 32 Bit IP Address 128 Bit IP Address

Pros and Cons of Using IPv6

IPv6 addresses have all the technical shortcomings present in IPv4. The difference is that it offers a 128 bit or 16-byte address, making the address pool around 340 trillion trillion trillion (undecillion).

It’s significantly larger than the address size provided by IPv4 since it’s made up of eight groups of characters, which are 16 bits long. The sheer size underlines why networks should adopt IPv6 sooner rather than later. Yet making a move so far has been a tough sell. Network operators find working with IPv4 familiar and are probably using a ‘wait and see’ approach to decide how to handle their IP situation. They might think they have enough IPv4 addresses for the near future. But sticking with IPv4 will get progressively harder to do so.

An example of the advantage of IPv6 over IPv4 is not having to share an IP and getting a dedicated address for your devices. Using IPv4 means a group of computers that want to share a single public IP will need to use a NAT. Then to access one of these computers directly, you will need to set up complex configurations such as port forwarding and firewall alterations. In comparison to IPv6, which has plenty of addresses to go around, IPv6 computers can be accessed publicly without additional configurations, saving resources.

Future of IPv6 Adoption

The future adoption of IPv6 largely depends on the number of ISPs and mobile carriers, along with large enterprises, cloud providers, and data centers willing to migrate, and how they will migrate their data. IPv4 and IPv6 can coexist on parallel networks. So, there are no significant incentives for entities such as ISPs to vigorously pursue IPv6 options instead of IPv4, especially since it costs a considerable amount of time and money to upgrade.

Despite the price tag, the digital world is slowly moving away from the older IPv4 model into the more efficient IPv6. The long-term benefits outlined in this article that IPv6 provides are worth the investment.

Adoption still has a long way to go, but only it allows for new possibilities for network configurations on a massive scale. It’s efficient and innovative, not to forget it reduces dependency on the increasingly challenging and expensive IPv4 market.

Not preparing for the move is short-sighted and risky for networks. Smart businesses are embracing the efficiency, innovation, and flexibility of IPv6 right now. Be ready for exponential Internet growth and next-generation technologies as they come online and enhance your business.