The Internet is expanding while IPv4 addresses remain finite. In a way, this has become a general truth. Back when the fourth version of the Internet Protocol was created, we thought 4 billion addresses would be more than enough.
That’s not the case anymore. As businesses, organizations, and networks grow more and more, IP addresses are getting more and more limited. With more than five billion Internet users, it’s just a matter of time before IPv4 will not be able to satisfy our needs anymore.
Which brings the question, ”what to do when you run out of IP addresses?” And that’s what we are going to answer in today’s article.
Move your company’s whole network to Class A or B private address range.
Private IPs are not routed on the Internet. They work exclusively within a private/local network, also known as LAN (Local Area Network). They are super useful to establish secure and reliable corporate networks. But what do you do when you run out of IP addresses for your network?
You can try moving your company’s network to another private IP class. Private IP addresses are part of specific private IP ranges reserved by the Internet Assigned Numbers Authority (IANA). They are classified into three ranges, as follows:
- Class A: 10.0.0.0–10.255.255.255 (a /8 mask);
- Class B: 172.16.0.0–172.31.255.255 (a /12 mask);
- Class C: 192.168.0.0–192.168.255.255 (a /16 mask).
They are not used to connect to the Internet, but rather to help devices within a local network communicate with each other. This means they can be reused even though they are not wide. So, it’s no surprise millions of private networks around the world make use of IPs from these classes.
But if your company operates on a huge private network, it’s possible the private IP range you are using might grow insufficient. What you can do is try classful networking and shift to a wider class. For example, classes A and B have masks that translate into even more available private IPs.
A /8 mask offers 16,777,216 addresses, and a /12 mask allows for 1,048,576 addresses. This should mitigate the risk of running out of IP addresses. Just make sure you correctly update all the DCHP settings and the routing rules.
When you run out of IP addresses, you can use subnetting to divide your existing network into multiple smaller sub-networks. Subnets accept bits from the IP address’s host part and use these bits to assign a number of smaller sub-networks inside the original network.
Each IP address consists of a subnet mask. This is divided into three classes: Class A, Class B, and Class C. All three include the subnet mask known as the default subnet mask. The subnet mask is used to determine the type and number of IP addresses required for a given local network:
- Class A: 255.0.0.0;
- Class B: 255.255.0.0;
- Class C: 255.255.255.0.
The subnetting process allows you to split a single Class A, Class B, or Class C network number into smaller portions. The subnets can be subnetted again into sub-subnets.
Subnetting helps you add smaller networks without the need to acquire additional IP addresses. Besides preserving the IPv4 lifespan, subnetting helps with fast and stable network traffic.
Use Network Address Translation (NAT)
One of the most important networking protocols, NAT is a clever way of keeping IPv4 alive. NAT allows multiple unique private IP addresses to share a single public IP address to connect to the Internet.
So, more devices transfer information with fewer public IP addresses. Translating private IPs into a single public address not only makes IP addressing more efficient, but it also acts as an extra layer of security.
This is why every network should use a NAT router or a firewall. When devices within a local network send online requests, NAT will change their private IPs into a single public IP. This will be used to access the Internet.
Once the requested data is ready to be sent back, the NAT router or firewall will reverse the translation and send the information to the correct device.
Switch to IPv6
IPv6 adoption is a logical follow-up of the IPv4 exhaustion. Since IPv5 never left the experimental phase, we skipped counting classes and moved right to the sixth version.
IPv6 was designed as a solution for the discrepancy between the growing nature of the Internet and the limited number of IPv4 addresses.
IPv6 uses 128-bit addresses, theoretically allowing 2^128, or approximately 3.4×1038 total addresses. That’s a lot of addresses, and this should easily cover global needs. IPv6 is an upgrade, and it offers several advantages such as:
- More efficient routing;
- Better packet processing;
- Increased security;
- Improved performance;
- End-to-end transparency.
IPv6 also enables ISPs to reduce their routing tables by making them more hierarchical.
With all these improvements, IPv6 could be a good solution if you are wondering what to do if you run out of IP addresses. But keep in mind that taking this step is not that easy. The IPv6 adoption process is slower than expected. For you to switch to this new version, you might need to upgrade the entire infrastructure of your company.
There are millions of routers and switches all over the Internet. Not all equipment is compatible with IPv6, and changing it has a financial impact. Keep that in mind.
Register for IPv4 auctions
IPv4 has become a commodity, the Internet’s real estate. And if it’s something valuable to be won, there’s also an auction. Many companies own lots of IPv4 blocks without actually using them.
In contrast, other companies are looking for IPv4 blocks as their current resources are running short. IPv4 auctions are a good way of getting your hands on additional ranges, as long as you actually win the auction.
Winning an IPv4 auction will help you replenish your resources. But first, it is important to make sure you meet the requirements for buying IP addresses. You can also opt for acquiring addresses through ‘’Buy Now’’ platforms that sell them, such as V4Escrow.
Consider IP leasing
Arguably the most efficient and hassle-free method of ensuring your business has the blocks it needs. When you run out of IP addresses, you can choose to lease them through IP brokers or dedicated marketplaces, like IPWAY.
Such marketplaces make it easier for companies that own IPs to lease them to companies that need them. Not only does this ensure transparency and trustful relationships, but it also comes with notable perks:
- It is cost-efficient and allows you to invest more in other important fields;
- You can lease the IPs for how long you need without any other commitment;
- You get the right IPs for your corporate needs;
- You get the IPs from trustworthy suppliers only. This means the IPs are clean and reputable, with no blacklisting history;
- You contribute to increasing the lifespan of IPv4 addresses, as they can be reused.
Dedicated marketplaces like IPWAY facilitate the IP leasing processes through an automated dashboard and relevant technical support. The result is that you get the IPs you need faster, safer, and more easily.
As the Internet exploded, IPv4 became insufficient for what the world needed. With more than 5 billion devices used across the world (and the World Wide Web), the IPv4 pool obviously depletes quickly.
But this does not mean we will no longer have IPv4 addresses to use. Whenever you ask yourself what to do if you run out of IP addresses, remember that there are ways to tackle this problem. As we saw earlier, there are both complex and less complex solutions. Technical adjustments like classful networking and subnetting work, but they are time-consuming.
Switching to IPv6 is not out of the question, either. On the contrary, it can bring many improvements, but also comes with a couple of drawbacks:
- It is being adopted slowly;
- Many devices are not compatible with IPv6;
- Upgrading the infrastructure is costly and time-consuming.
What you can do, instead, is acquire them from selling platforms, auctions, or, even better, leasing them. Leasing helps build a healthier ecosystem. It helps companies monetize their unused IPs, and it helps other companies get the addresses they need. IP brokers and dedicated marketplaces will make sure the relationship between lessors and lessees is transparent, reputable, and helpful.