What Does IPv4 Exhaustion Mean to You?

By Walid Janjua

This is a Guest Post by Walid Janjua, who is a self professed technology geek and open source advocate. He is providing consulting in Data Networks, VoIP networks, Visualization and Business Process Automation to small and medium companies in Islamabad/Rawalpindi.

naptlogoThese days you can not visit a technology blog or a major news portal without reading about the looming catastrophe of IPv4 exhaustion. Some people are claiming that this is going to be the death of the internet and others suggest that a solution is available and the average user will not even feel the difference.

For most non-technical people, they have never really heard of the term before, let alone what it does and how it is going to effect them. I am going to try to explain the entire problem and its effects on you.

What Rally is IPv4?

On the internet every computer has a unique address. Think of this as your telephone number. If someone wants to contact you, he/she is going to call you by dialing your number.

The same way, every internet connected device (for instance your computer is a device connected to internet) requires its own unique internet address, or an IP address.

On a very basic level, different IP addresses communicate with each other to make the magic of the internet possible. It is worth mentioning here that in most cases the IP addresses are unique for each of the device connected to the internet.

The problem:

The current incarnation of the above mentioned system (IPv4), dates back to research carried out in the 1970′s and 1980′s. Since then it really has not changed all that much.

The problem with the current system is that they are not enough unique IP addresses within the system to assign to every person or device which wants to connect to the internet.

The body which governs the allocation of IP addresses IANA (Internet Assigned Numbers Authority), has already assigned all of the remaining pools of of IP addresses to regional bodies (RIR’s) to be further allocated to companies and individuals. Now, that there are no more IP address available to assign, what do we do if someone wants to connected to the internet.


In the very short term, the remaining IP address which have been assigned to RIR’s will need to be allocated to service providers and businesses in such way that it is ensured that they are only assigned to those originations which really need them. But this is certainly not a real solution. Other solutions do exist which we will look at.


NAT stands for Network Address Translation. With NAT, an entire network is assigned only one public internet address (public IP address). All the hosts within the network are assigned a Private address with which they can not communicate with the internet but they can communicate with each other over the private network.

Within the network a server or a router is performing NAT. The server/router accept requests from the hosts on the private network on their private addresses to connect to the internet.

The router/server then sends out the requests over the internet using its public internet IP address. This arrangement has a lot of inherent issues. Hosts within the network will not be able to host web services e.g. a web host, a public DNS server etc. with using something called Port Forwarding.


The only real solution to the problem is the adoption of IPv6. With IPv6, the size of the available IP address has been changed many fold.

In IPv4 the maximum available IP address are 4,294,967,296. However, almost half of them have been reserved for other other purposes.

On the other hand, IPv6 has 340,282,366,920,938,000,000,000,000,000,000,000,000 unique addresses.

To put this into perspective, that is approximately 5×1028 addresses for each of the roughly 6.5 billion people alive today. Unfortunately, a significant portion of the internet core infrastructure is not ready for this transition to IPv6.

In some cases only a software patch can fix the issue but in more severe cases, the hardware needs to be replaced. In the medium term, both IPv6 and IPv4 will have to be used simultaneously.

Adoption of IPv6

Most companies and large internet service providers have been very slow in adoption of the new protocol. As it stands, only a handful of service providers are offering IPv6 based connections. According on study, only 1.81% of all the devices connected are connected over IPv6.


Certainly the future is IPv6 but the adoption has been at a snails pace. If IPv6 is not adopted on a state level, many disruptions can be expected within the medium term. I would recommend everyone to contact their service provider to seek IPv6 connectivity. Sooner or later, everyone has to take the plunge.