IPv4 exhaustion is not a new issue. In fact, experts predicted this problem over a decade ago. Every device connected to the internet must have an IP address to act as an identifier in order to communicate. Due to the limited design of IPv4 addresses, it has long been understood that we were dealing with a finite resource. However, what was not understood at the time was the impending popularity of the World Wide Web.
The problem with IPv4
IPv4 IP addresses are 32-bit binary numbers used as addresses in the IPv4 protocol. The protocol follows a basic numerical formula that follows 2^32. This means that in total, there are 4,294,967,296 unique IPv4 addresses available. However, as there are 7.3 billion people on the planet we are already three billion IP addresses short, and that’s assuming that each individual needs only one – which isn’t the case as many of us have multiple devices. In reality, IPv4 addresses are currently in extremely short supply and arrangements have been in process for years to attempt to alleviate the shortage.
There are three different types of IP addresses, public, private, and special purpose IPs used by The Internet Assigned Numbers Authority (IANA), which we will not cover in this article. Since there are a limited number of IPv4 addresses, the Internet Engineering Task Force has set regulations about which IPs can be used for various purposes.
For example, in total, there are 588,514,304 IP addresses that have been reserved for special purposes. There are 4,294,967,296 IPv4 addresses total, leaving 3,706,452,992 addresses for public use. These simple calculations mean that there are even fewer options for IP addresses for the average user. You can see the entire Reserved IP Address range here.
IPv4 is now facing the very last of the IP addresses to be assigned, which has been referred to as the /8 pool. According to RIPE NCC “A network numbered “10.0.0.0/8” (which is one of those reserved for private use) is a network with eight bits of network prefix, denoted by “/8” after the oblique. The “8” denotes that there are 24 bits left over in the network to contain IPv4 host addresses: 16,777,216 addresses to be exact.”
To resolve this issue, two different situations have been put into play. One, Public IPv4 address assignments, and, two, the creation of IPv6 addresses.
The Internet Registry System
Since we are in the end stages of Public IPv4 availability, The Internet Registry System has decided upon a democratic way of dispersing the remaining IP addresses. The guidelines below outline the deciding factors of IPv4 address assignments according to RIPE NCC:
“Public IPv4 address assignments should be made with the following goals in mind:
- Uniqueness: Each public IPv4 address worldwide must be unique. This is an absolute requirement guaranteeing that every host on the Internet can be uniquely identified.
- Aggregation: Distributing IPv4 addresses in a hierarchical manner permits the aggregation of routing information. This helps to ensure proper operation of Internet routing.
- Fairness: Public IPv4 address space must be fairly distributed to the End Users operating networks.
- Registration: The provision of a public registry documenting address space allocations and assignments must exist. This is necessary to ensure uniqueness and to provide information for Internet troubleshooting at all levels.”
RIPE NCC is a not-for-profit organization that allocates and registers blocks of IP numbers to Internet service providers (ISPs) and other organizations. Membership to RIPE NCC depends on the host’s ability to adhere to the guidelines above. Businesses and organizations place great importance on being seen as a fair IP allocating organization, leading many to change their practices to adhere to RIPE NCC guidelines.
IPv6 is a new protocol for IP addresses that have a size of 128-bit compared to IPv4’s 32-bit protocol. The length of the IPv6 address has 2^128 or 3.4×10^38 addresses available. In total, this number amounts to 340,282,366,920,938,463,463,374,607,431,768,211,456 different unique IPv6 address. That’s approximately 340 undecillion! IPv6 presents an excellent option for remedying IP address issues.
The combination of the situations above has resulted in stricter rules regarding IP addresses. While many hosting companies still have IPv4 addresses available, many have readdressed their protocols and procedures regarding assignment practices. Be sure to discuss IPv4 practices with your hosting provider to understand how many IPs will be provided as well as the fees associated with adding IPs to your account.