IPv4 & IPv4.Global Basics

by Leo Vegoda

What is IPv4?

Every device connecting to the internet must have a numerical address. That address is part of a block of addresses used by a network. The smallest block that can be used on the internet is 256 IPv4 addresses.

Rules for numbering (addressing) devices are called the Internet Protocol (IP). These rules define the format of an address so data can travel from network to network and arrive at the intended destination. Nearly all internet-connected devices each have a unique IP address.

Internet Protocol version Four (IPv4) was the first version of the Internet Protocol put into production. Almost all the IPv4 addresses have already been allocated. It is still the most popular version of the Internet Protocol. IPv6 is newer but less than half of all internet traffic uses it.

What are RIRs?

Each continent has a registry that lists who is using IPv4 and IPv6 addresses. This helps to ensure that one IP address isn’t duplicated anywhere. It also helps network operators coordinate with each other when there is a technical problem.

These Regional Internet Registries (RIRs) perform a similar function to a land registry. They make sure that the registrant is a real person or organization. They make sure they have contact details for the registrant.  They have rules, developed by the public, detailing who is eligible to get how many addresses.

What are IPv4 transfers?

Since the RIRs have given out all of the IPv4 addressses, the only practical source of IPv4 addresses is other networks. Motivating someone with a network to renumber and given up an asset requires compensating them, so RIR policy allows for organizations to transfer their addresses in part or in whole to another organization.

In the early days of the internet computing was expensive and addresses were free. IPv4 addresses were allocated in three block sizes: large, medium, and small (Class A, B, and C) to make things easier for the slow and expensive computers of the time.

But computing is now much cheaper. As the RIRs saw that they would run out, new technology was developed to allow sizes in between large, medium, and small. This meant the RIRs could give out only as many addresses as were immediately needed. This increase in efficiency delayed the IPv4 runout for many years. What’s more, an organization that had a medium size block might be able to sell half of it. One network can use multiple blocks of different size if they are needed.

What are IPv4 Waitlist services?

Some RIRs have policies to help new market entrants get some IPv4 addresses from a small, reserved pool. Most of this pool comes from addresses returned when organizations go out of business. RIRs typically see about 100,000 IPv4 addresses come back each year – but it varies.

Getting IPv4 addresses directly from an RIRs’ is less costly than buying them on a marketplace but this comes at the cost of a long wait. To get a small number of addresses direct from an RIR, you’ll wait at least two years after joining the ARIN or RIPE NCC waitlists!

How IPv4.GLOBAL Qualifies Registrants

IPv4.Global reviews the organizations we do business with. We make sure the seller has the addresses and the buyer is real. We look at the individuals representing those organizations to make sure they are actually employed there. RIRs also review this information as a part of their due diligence checks. The RIPE NCC documents what they check. The other RIRs check these things, too, each with slight nuances.


IPv4.GLOBAL protects both buyers and sellers with an escrow service. It also offers a third-party alternative through its partner escrow.com. IPv4.GLOBAL has negotiated a 20 percent discount on the escrow.com fees for our clients.

Payment options

Card payments

With IPv4.GLOBAL, you can pay on a card for transactions up to $30,000. In 2023, that’s enough to buy up to a /22 (1,024 addresses). Learn more about IPv4 block sizes and CIDR.

Time to transfer


AFRINIC does not support inter-region transfers yet. AFRINIC policy does allow transfers within the region but there have not been many. AFRINIC policy requires organizations to return addresses that are not being used, and so transfers are uncommon.


ARIN has an efficient transfer process. Transfer tickets typically take less than a week. Some have completed in a single business day. Providing all organizational background documents speeds up the ARIN process. Our transfer experts can advise you on the documents you’ll need.


APNIC has an efficient transfer process. Clients in Europe and the Americas should be aware that APNIC’s business day ends before theirs starts. So inter-RIR transfers involving APNIC take a couple of extra days. APNIC’s responses typically come the day after a message from Europe or the Americas.


The RIPE NCC has an efficient transfer process. Transactions typically take just a couple of days. We can guide you through their process.


LACNIC’s process is still developing. Transactions typically take several months. Transactions require wet ink signatures from all parties. This means moving a paper document around the world. Response times on tickets are often several days or weeks. This longer process often drives a lower price for IP address transactions involving LACNIC.


Hold period

The RIRs want IP addresses to be used for internet connections. To reduce speculation by investors who won’t actually use the addresses, some of them require organizations to hold the addresses for a period before transferring them again.

  • APNIC – Allocations from must be held for five years before being transferred. There is no hold period for transfers from other blocks.
  • ARIN – ARIN requires addresses to be held for five years after being issued from the waitlist, or 12 months for other space. The hold does not apply to addresses acquired through mergers and acquisitions.
  • LACNIC – Transferred addresses must be held for a year before being transferred again
  • RIPE – IPv4 addresses must be held for two years before being transferred, including addresses acquired through M&A. The hold does not apply for legacy addresses if treated as a legacy update.

Legacy status

Some organizations got IP addresses before the RIRs existed. Those IPv4 addresses have a special legacy status. One advantage of the legacy status is lower fees or no fees. But it comes at the cost of access to fewer services. For instance, organizations using legacy IP addresses can’t get RPKI certificates for them from ARIN without signing an agreement.

When legacy addresses are transferred within ARIN, APNIC, or LACNIC they lose their legacy status. But when they are transferred within the RIPE region they can retain their legacy status. This also applies to legacy transfers from APNIC to RIPE. This is advantageous for some organizations, like treaty organizations or government bodies who cannot become a member of another organization. It also means that the hold timer does not apply, and the buyer can immediately transfer their address space.

Some organizations value legacy status and will pay a premium for legacy addresses. Many others don’t care.

Other considerations

GeoIP status

Many companies rely on knowing where an IP address is to provide a service. Some video streaming is only available to specific regions. Some banks see hacking attempts from other countries and block addresses listed there. Some web sites simply use the best known location of the IP address to decide what language to show.

Information about the geographic location of a device based on IP address (GeoIP) comes from several sources, and is sometimes unreliable. Network operators can publish information giving information about GeoIP in an appropriate level of detail to help their users and these other services. IPv4.GLOBAL can help in publishing this information.

IRR registration

Anyone can run an internet network. When a new network comes online, they “announce” their IP addresses to their neighboring network(s). To protect against mistakes bringing a network offline or addresses being announced by the wrong network, many network operators register their internet connections in Internet Routing Registry (IRR) databases. Networks build filters that limit the scope of misconfigurations. It’s important to register a policy and IPv4.GLOBAL can show you how.


Misconfigurations can cause outages. RPKI was developed to provide a more secure version of the IRR databases. It uses digital certificates to reduce “fat finger incidents” or intentional hijacking. It’s a way to link IP addresses with the number identifying the network announcing them. That number is an Autonomous System Number (ASN). The RIRs are making it easier to create and renew your RPKI records. IPv4.GLOBAL can help get it set up.


Some people send spam and attack networks. Several databases have been established to collect and report information on the reputation of the IP addresses where this happens.  Organizations use them when deciding whether to accept mail, or even let their users load certain web pages.

IPv4.GLOBAL can help assess the reputation of IPv4 addresses, and can help clean up that reputation when the bad actors have been removed and vulnerabilities have been blocked.