# data[].attributes.body
Summary:
This article explains that there were only 1 million IPv4 addresses left at the time of writing in 2019. The article predicted that all of the IPv4 addresses would be used in by November 2019.

Reflection:
The author of the article offered a solution to reduce the number of IPv4 addresses in use. By ISPs and server farms further relying on network address translation, more IPv4 addresses can be conserved. It is interesting that the article only briefly touch on IPv6 as a solution mentioning that switching to it is harder than anyone ever imagined.

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RIPE, which manages IP address distribution for a large part of the world, has updated its address space chart showing how many addresses are left. It is clear that unless something unexpected happens RIPE will run out of addresses in November.

The IPv4 crisis has been going on so long now that it is tempting to say "crisis, what crisis!" There are about 4 billion IP addresses and now we are down to just 1 million. That sounds a lot, but users tend to want blocks of many addresses and 1 million for the foreseeable future isn't enough. There is already, from October 2nd, a limit to only /22 blocks (1024 addresses) being allocated and this will fall to /24 blocks (256 addresses) once the well dries up. At this point applicants will form an orderly queue and wait for IP address allocations to be returned to RIPE. Only applicants who have never received an IP allocation will be added to the queue.

What effect will this have?

In most cases end users don't apply for IP addresses directly - they get them from their ISP or from their cloud or server provider such as 192.168.1.1 and 192.168.0.1.

. So for most users it isn't a matter of when RIPE runs out, more what happens when their ISP or server provider runs out. A recent survey by RIPE suggests that about a third ranked IPv4 run-out as a top three challenge and more than half said that they needed more IPv4 addresses in the next 2 to 3 years.

Of course, like any resource run-out, estimates of doom and gloom are generally too pessimistic. Clever thinking makes the best of the situation. IPv4 has been hugely extended by the use of dynamic address allocation and Carrier Grade NAT. ISPs can now operate their service with fewer IP addresses. Companies which have stockpiled IPs are now able to make a profit on switching to NAT and selling their surplus IP addresses. It seems unlikely that November 2019 will go down in history as the day the IPv4 well ran dry, but things are going to get much more difficult.

When you think that IPv4 has 4 billion addresses and only servers need a fixed IP, it doesn't seem reasonable that we have used them all up. Perhaps it is time to force companies to relinquish IP addresses that are needlessly allocated to servers that could just as easily be port-mapped. Can we do this automatically? Is it possible to scan IP addresses and make a list of uses that could be converted to NAT and port-mapping without a loss of functionality? We have spent a lot of effort getting everyone to upgrade to HTTPS, and this particular upgrade is arguably more important.

We have been profligate with a resource that when first introduced seems so limitless that we could allocate huge blocks of addresses and let anyone use them as they wanted to without any penalty.

Surely the answer is IPv6, which really is a limitless address space?

Yes, but changing over seems harder than anyone ever imagined.

More Information
RIPE NCC IPv4 Available Pool
Related Articles
IPv6 Is A Failure - Time To Move On IPv6 Day - The Internet Just Got Bigger Happy IPv6 - too little and so what! IPv6: The Programmer's View Fast Running Out Of IPv4 addresses
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# data[].attributes.attachment_link.description
RIPE, which manages IP address distribution for a large part of the world, has updated its address space chart showing how many addresses are left. It is clear that unless something unexpected happens RIPE will run out of addresses in November.

# data[].attributes.body
Summary:
This article explains that internet service providers are sharing IPv4 addresses amongst themselves, prolonging the painful switch to all IPv6. Many large corporations are already using IPv6, but the full switch cannot happen if anyone is still supporting IPv4.

Refection:
I agree network address translation and other techniques used to continue support for IPv4 are only temporary solutions to a long term problem. IPv6 will need to be widely supported at some point even if the switch will be somewhat painful. The US and China plan to adopt IPv6 100%, but I think the transition date keeps getting pushed back. The longer we wait, the more painful the move will be.

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Back in November 2019, the RIPE NCC (the regional Internet registry for Europe, West Asia, and the former USSR) announced that it had exhausted its pool of IPv4 addresses. We have been anticipating and warning of this for a long time ( since the late 1980s), so it was not a huge surprise when it happened.

In fact, a whole other Internet protocol, IPv6, was designed way back in the mid-nineties as a solution to this problem. It was already a tried and tested technology by the time we reached the run-out and offers 340 trillion, trillion, trillion IP addresses. It felt like the hard bit was done. But unfortunately, that's not the case.

Convincing ISPs to make the jump to the new protocol to future-proof their networks isn't easy. Even a year after the official run-out, a large number of ISPs are yet to make the jump and enable IPv6 in their network. A common attitude exists that upgrading to IPv6 will be a risky and expensive project, or one simply not needed for businesses with enough IPv4 addresses, for now at least.

For too long, sticking with IPv4 has been the easy approach. But we're reaching a point where that's not necessarily true anymore. So, one year on, where do we stand?

Sticking to IPv4 is coming at a cost

With the emergence of a secondary IPv4 market, ISPs have found a way to put off the deployment of IPv6. By transferring unused IPv4 addresses amongsst themselves, ISPs are able to grow their networks without giving IPv6 a thought.

However, what we've seen in the last year is that the cost of IPv4 addresses is climbing - a single used address can currently go for $25-$30 on the IPv4 transfer market. The market itself is hugely unpredictable. As prices of IPv4 addresses are entirely subject to supply and demand, growing a network in this way is costly and difficult to manage. It's only logical that as Internet connections grow and demand rises, the price will continue to climb.

Those ISPs taking this short-term approach might find themselves priced out of the market. We know that the secondary market is very much dominated by a few large cloud providers, who are often have little choice but to keep supporting IPv4 alongside their IPv6 offerings.

Recently a report emerged that showed how Amazon had already acquired over 100 million IPv4 addresses, estimating an investment in the region of $2.5 billion on address space alone. A sizeable investment that only companies with very deep pockets can afford.

The other alternative that has seen traction is Carrier Grade Network Address Translation (CGNAT), which prolongs the life of IPv4 addresses by allowing a single IP address to be shared across several thousand devices. But this is presenting its own problems: as CGNAT is unable to scale indefinitely. Every time a NAT is layered, the chances of failure in the network increases. When a CGNAT goes down, thousands of users can suffer the impact.

A year later, it is more evident than ever that these 'solutions' are short-term at best, and that the fundamental issue still remains: there are simply not enough IPv4 addresses to go round.

Is it all doom and gloom?

Although uptake has been slow, IPv6 deployment rates have in fact improved in recent months, with 68 percent of Local Internet Registry accounts now holding IPv6 addresses and 30 percent of networks (ASes) announcing an IPv6 prefix within the RIPE NCC service region. Currently, the RIPE NCC is issuing around 50 IPv6 allocations per week, rising to 80 during busier periods. And of the five Regional Internet Registries (RIRs), we are leading in IPv6 adoption, followed by APNIC which covers the Asia-Pacific region.

Globally, the industry has seen big tech players such as Google, Facebook and Apple lead the way and show their support for IPv6. This is having a significant effect in showcasing the benefits of deploying the new protocol today. By enabling IPv6 connectivity to end users, networks are seeing a significant portion of their traffic moving over it thanks to these content providers. T-Mobile 's network in the US, for example, now runs 91 percent of its Internet traffic over IPv6.

Progress is being made and that is set to continue as IPv6 remains more affordable than IPv4 in the long-term. However, we're still some way off saying goodbye to IPv4 altogether. It's not yet feasible to run an IPv6-only network when customers still require access to content or services that are running over IPv4. What we are learning though is that businesses can be strategic about how much IPv4 they really need. Some ISPs - including several large ones, like Facebook - are running IPv6-only internal networks, providing IPv4 only at the end where their customers and users require it.

The push towards nationwide deployment plans for IPv6 also offers hope. Several governments, including China and the US, are preparing plans to drive 100 percent nationwide IPv6 adoption in the next few years. In a recent publication on the EU's cybersecurity strategy, the European Commission also stated that they would not exclude "regulatory measures like a European sunset clause for IPv4 to steer the market if there is insufficient progress towards [IPv6] adoption." We expect such measures to have a profound impact on the global development of IPv6.

IPv6 one year from now

Looking back on previous years, the main causes for concern over IPv6 have been on cost and the risks involved in its deployment. But it's now the increasing cost and challenges associated with IPv4 that are tipping the scales in favour of IPv6. These are the key drivers that are beginning to inspire the positive growth we are seeing in IPv6 adoption.

We still have a long way to go and we don't know when exactly those scales will shift for everyone. What we do know is that IPv6's extended address space is the only way to support the ever-growing networks. Something IPv4 simply no longer offers to support. We can expect to see more and more ISPs, content providers and national governments wake up to this in 2021.

With an almost inexhaustible amount of IP addresses, ISPs can start to discover how IPv6 can offer efficiency and affordability. A long-term strategy for IPv6 will save them money, ready them for the future, and enable sustainable Internet growth.

# data[].attributes.attachment_link.description
Back in November 2019, the RIPE NCC (the regional Internet registry for Europe, West Asia, and the former USSR) announced that it had exhausted its pool of IPv4 addresses. We have been anticipating and warning of this for a long time ( since the late 1980s), so it was not a huge surprise when it happened.

# data[].attributes.body
Summary:
IPv4 and IPv6 are two completely different protocols and are not compatible with each other so the internet will have to run a dual IP stack for the foreseeable future. The last IPv4 address was predicted to be given out in 2013, so the sooner businesses and ISPs switch to IPv6, the more prepared they will be in the future.

Reflection:
We still have an IPv4 address pool, so the last address was not given out in 2013 because of techniques used to temporarily continue support for IPv4. But I agree that the sooner businesses switch to version 6, the more prepared and future proofed they will be. supposedly, IPv6 has more addresses than we could ever dream of using (that's exactly what they said in the 1970s about IPv4), so when the switch happens, engineers don't have to keep making techniques to keep supported the old IPv4 protocol.

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IPv6: When do you really need to switch? | ZDNet

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World IPv6 Day, 6 June, 2012 is here, and with it many ISPs, websites and manufacturers are now supporting IPv6, the next generation network protocol of the internet. For many users, though, the questions of what, when and why still await answers. Everyone in networking knows that they should be switching to IPv6.

# data[].attributes.body
Summary:
IPv6 not only provides more address space than IPv4, but also more security. Many small and medium sized businesses are not switching to IPv6 because they have no incentive to do so and they believe that the switch will cause down time.

Reflection:
There has been resistance to switching to IPv6 because it is unfamiliar and introduces new terminology and algorithms with IT professionals will have to learn. This can all lead small and medium sized businesses to not prioritize the switch to IPv6. This will further prolong the switch to the new protocol. IPv6 and IPv4 are not compatible protocols, so IPv4 will have to be totally removed before the internet can stop supporting it.

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For the most part the dire warnings about running out of internet addresses have ceased because, slowly but surely, migration from the world of Internet Protocol Version 4 (IPv4) to IPv6 has begun, and software is in place to prevent the address apocalypse that many were predicting.

But before we see where are and where we're going with IPv6, let's go back to the early days of internet addressing.

What is IPv6 and why is it important?

IPv6 is the latest version of the Internet Protocol, which identifies devices across the internet so they can be located. Every device that uses the internet is identified through its own IP address in order for internet communication to work. In that respect, it's just like the street addresses and zip codes you need to know in order to mail a letter.

The previous version, IPv4, uses a 32-bit addressing scheme to support 4.3 billion devices, which was thought to be enough. However, the growth of the internet, personal computers, smartphones and now Internet of Things devices proves that the world needed more addresses.

Fortunately, the Internet Engineering Task Force (IETF) recognized this 20 years ago. In 1998 it created IPv6, which instead uses 128-bit addressing to support approximately 340 trillion trillion (or 2 to the 128th power, if you like). Instead of the IPv4 address method of four sets of one- to three-digit numbers, IPv6 uses eight groups of four hexadecimal digits, separated by colons.

What are the benefits of IPv6?

In its work, the IETF included enhancements to IPv6 compared with IPv4. The IPv6 protocol can handle packets more efficiently, improve performance and increase security. It enables internet service providers to reduce the size of their routing tables by making them more hierarchical.

Network address translation (NAT) and IPv6

Adoption of IPv6 has been delayed in part due to network address translation (NAT), which takes private IP addresses and turns them into public IP addresses. That way a corporate machine with a private IP address can send to and receive packets from machines located outside the private network that have public IP addresses.

Without NAT, large corporations with thousands or tens of thousands of computers would devour enormous quantities of public IPv4 addresses if they wanted to communicate with the outside world. But those IPv4 addresses are limited and nearing exhaustion to the point of having to be rationed.

NAT helps alleviate the problem. With NAT, thousands of privately addressed computers can be presented to the public internet by a NAT machine such as a firewall or router.

The way NAT works is when a corporate computer with a private IP address sends a packet to a public IP address outside the corporate network, it first goes to the NAT device. The NAT notes the packet's source and destination addresses in a translation table.

The NAT changes the source address of the packet to the public-facing address of the NAT device and sends it along to the external destination. When a packet replies, the NAT translates the destination address to the private IP address of the computer that initiated the communication. This can be done so that a single public IP address can represent multiple privately addressed computers.

Who is deploying IPv6?

Carrier networks and ISPs have been the first group to start deploying IPv6 on their networks, with mobile networks leading the charge. For example, T-Mobile USA has more than 90% of its traffic going over IPv6, with Verizon Wireless close behind at 82.25%. Comcast and AT&T have its networks at 63% and 65%, respectively, according to the industry group World Ipv6 Launch.

Major websites are following suit - just under 30% of the Alexa Top 1000 websites are currently reachable over IPv6, World IPv6 Launch says.

Enterprises are trailing in deployment, with slightly under one-fourth of enterprises advertising IPv6 prefixes, according to the Internet Society's "State of IPv6 Deployment 2017" report. Complexity, costs and time needed to complete are all reasons given. In addition, some projects have been delayed due to software compatibility. For example, a January 2017 report said a bug in Windows 10 was "undermining Microsoft's efforts to roll out an IPv6-only network at its Seattle headquarters."

When will more deployments occur?

The Internet Society said the price of IPv4 addresses will peak in 2018, and then prices will drop after IPv6 deployment passes the 50% mark. Currently, according to Google, the world has 20% to 22% IPv6 adoption, but in the U.S. it's about 32%).

As the price of IPv4 addresses begin to drop, the Internet Society suggests that enterprises sell off their existing IPv4 addresses to help fund IPv6 deployment. The Massachusetts Institute of Technology has done this, according to a note posted on GitHub. The university concluded that 8 million of its IPv4 addresses were "excess" and could be sold without impacting current or future needs since it also holds 20 nonillion IPv6 addresses. (A nonillion is the numeral one followed by 30 zeroes.)

In addition, as more deployments occur, more companies will start charging for the use of IPv4 addresses, while providing IPv6 services for free. UK-based ISP Mythic Beasts says "IPv6 connectivity comes as standard," while "IPv4 connectivity is an optional extra."

When will IPv4 be "shut off"?

Most of the world "ran out" of new IPv4 addresses between 2011 and 2018 - but we won't completely be out of them as IPv4 addresses get sold and re-used (as mentioned earlier), and any leftover addresses will be used for IPv6 transitions.

There's no official switch-off date, so people shouldn't be worried that their internet access will suddenly go away one day. As more networks transition, more content sites support IPv6 and more end users upgrade their equipment for IPv6 capabilities, the world will slowly move away from IPv4.

Why is there no IPv5?

There was an IPv5 that was also known as Internet Stream Protocol, abbreviated simply as ST. It was designed for connection-oriented communications across IP networks with the intent of supporting voice and video.

It was successful at that task, and was used experimentally. One shortcoming that undermined its popular use was its 32-bit address scheme - the same scheme used by IPv4. As a result, it had the same problem that IPv4 had - a limited number of possible IP addresses. That led to the development and eventual adoption of IPv6. Even though IPv5 was never adopted publicly, it had used up the name IPv5.

Copyright © 2020 IDG Communications, Inc.

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What is IPv6, and why aren't we there yet?

# data[].attributes.attachment_link.description
For the most part the dire warnings about running out of internet addresses have ceased because, slowly but surely, migration from the world of Internet Protocol Version 4 (IPv4) to IPv6 has begun, and software is in place to prevent the address apocalypse that many were predicting.

# data[].attributes.body
Summary:
The IPv4 address crisis has not been talked much about lately. This is because engineers have figured out ways to conserve IPv4 address space. But, this fix is only temporary and will only last for a short amount of time.

Reflection:
While the IPv4 addresses have been conserved with new technology like network address translation, I agree that these solutions are only temporary. There will soon come a time that everyone will need to switch over to IPv6 to fix the issue one and hopefully for all. This will require educating IT departments about IPv6 and the issue with IPv4

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Whatever happened to the IPv4 address crisis?

# data[].attributes.attachment_link.description
In February 2011, the global Internet Assigned Numbers Authority (IANA) allocated the last blocks of IPv4 address space to the five regional Internet registries. At the time, experts warned that within months all available IPv4 addresses in the world would be distributed to ISPs.

# data[].attributes.body
Summary:
The IPv4 crisis started back in 1992 and the crisis seamed like a very big deal. But, in the next few years, the introduction of classless inter-domain routing and network address translation made the issue seam less severe. Now in 2022, we are still in the mist of the IPv4 crisis.

Reflection:
It is amazing that we have been dealing the IPv4 address crisis for 30 years now. The longer we wait to do a mas transition to IPv6 the harder it will be to switch over. The implementation of zip tie fixes to the IPv4 internet are becoming more permeant than they should.

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I bet that nobody believed in 1992 that thirty years later, we'd still be discussing the state of the transition to IPv6! In 1992 we were discussing what to do about the forthcoming address crunch in IPv4, and having come to terms with the inevitable prospect that the silicon industry was going to outpace the capacity of the IPv4 address pool in a couple of years, we needed to do something quickly. We decided to adopt a new protocol, IP version 6, a couple of years later, and in December 1995, the IETF published RFC 1883, the specification of IPv6.

There were many views as to how long the transition from IPv4 to IPv6 would take, from an optimistic six-month rapid cutover to a hopelessly pessimistic view of a protracted ten-year transition. If there was a prevalent view at the time, it was that the transition would take a further five years or so. But don't forget that this was in the lead-up to the Internet Bubble of 2000. Anything likely to happen five years out was shelved as a "tomorrow" problem. At the same time, we toiled away on the "today" issues of adding more carriage capacity to the network, fixing the myriad of issues with routing, and making dial-up modem access work!

While this was a pressing issue in 1992, four years later, in 1996, there was no longer any particular sense of urgency about the transition to IPv6. Why not? There are four major reasons for the shift in attitude.

Firstly, we changed the address plan for the Internet, and by 1994 we had introduced so-called classless inter-domain routing (CIDR). Instead of three classes of fixed size network prefixes, we could tailor each network to use an address prefix size more in line with the current size and short-term expectations of host count for the network, rather than the coarse selection of 256, 65,536 or 16,777,216 hosts in the old Class ABC plan.

Secondly, we were not running out of IPv4 addresses as such. The immediate problem was running out of Class B address prefixes. By adopting classless routing, we were able to make a dramatic change in the annual rate of address consumption and the IPv4 address exhaustion issue lost most of its immediacy. Exhaustion was still going to happen, but not within the next year or two.

Thirdly, we added more resources to support the function of address allocation with the introduction of the Regional Internet Registry (RIR) system, and with greater oversight of these allocations and a greater emphasis on address conservation and higher efficiency, the rate of address consumption slowed down considerably through the latter half of the 1990s.

Finally, the ISP industry turned to using NATs in its services. Individual IP addresses were shared across multiple simultaneous connections by port multiplexing and timeshared by reusing an address across different connections.

The result of these factors can be seen in a plot of the annual IPv4 address allocations since 1985 (Figure 1). The outlook in 1990 was a rapid growth in address allocations that would consume the entire address space within a few years. By 1995, the effects of CIDR, NATs and the RIR system had not only reversed this consumption growth trend but suppressed it completely. The 1999 address consumption rate of just under 50M addresses per year implied that the IPv4 address pool would last for a further 50 years and any sense of urgency about IPv6 transition largely dissipated.

This was not a stable situation, and there were two critical technology developments at that time that once again re-shaped the environment. The first was the adoption of DSL as a last-mile access technology. Dial-up Internet was only for the most stalwart and determined of users. The adoption of DSL transformed this into an 'always on' technology, allowing the Internet to transform into a supposedly seamless consumer product. The second was the introduction of mobile IP services, fuelled by the introduction of the iPhone in 2007. The combination of these technologies created a second wave of expansion of the Internet that once more overwhelmed the existing infrastructure and rewrote all the plans we had at that time. By 2007 the IP address consumption volumes were back to their 1992 peak of 200M addresses per year, and at this time, it was clear that, once more, IPv4 had a far more finite lifetime.

In 2007, IPv4's further lifetime expectations had shrunk back from decades to a small number of years. However, this time around, the looming IPv4 address crunch did not motivate a new enthusiasm to complete the transition to IPv6 rapidly. The change in the consumption pattern occurred so rapidly that by the time it was clear that we no longer had decades to complete this transition, it was also clear that we had just a handful of years. The Internet had grown large enough at that time that a couple of years was just not enough time to perform a detailed technology transition across the entire Internet, which by 2008 was a far larger Internet than the Internet of 1995.

Predictably, in the face of an impossible alternative, the industry took the other path and performed a run on the remaining pools of IPv4 addresses. The year 2010 represented 'peak IPv4' in terms of address allocations, and some 250M IPv4 addresses were allocated throughout the year. In early 2011, the unthinkable inevitably happened. The 'warehouse' of IP addresses, the IANA, handed out its last address blocks to the RIRs. This was unthinkable because we were never meant to drain the well of addresses completely. We were meant to behave more prudently. We were meant to have completed this transition to IPv6 well before we ever got to this point.

But by 2011, our collective response was not a hastened effort to complete the transition to IPv6 because by then this rapid transition was not a realistic option anymore. No matter what we did, we would have to operate the Internet while running on depleted stocks of further IPv4 addresses. This situation triggered the adoption of a far more conservative regime of IPv4 address allocation by the RIRs. The measures were intended to support a prolonged zombie life of IPv4 by reducing the allocation volumes such that the intense use of NATs was now necessary. It may have been that the underlying objective was to make IPv6 an attractive alternative to NATs and IPv4. The result was different, and it was ultimately the final nail in the coffin for a general peer-to-peer networking model for the Internet. The Internet became a monoculture of client/server network, permitting even greater intensity of the use of NATs within the network's infrastructure.

There are two visible threads in the continued evolution of the Internet today. One is the further consolidation of the client/server model of the Internet with attention being focussed on the server-side of the network with the primacy of content distribution networks, and the shrinking of the client-side networks, the residual visible part of the Internet, to last-mile single-hop access networks. The other thread is this transition to IPv6.

The near-term directions in the client/server models are driven by pressures to consolidate further and use a smaller number of very large access networks in each market. Like the mobile network infrastructure landscape, each national market is shrinking down to at most three consumer network infrastructure operators and a collection of retail resellers. This infrastructure consolidation permits the major Content Distribution Networks (CDNs), who are also consolidating, to place their points of delivery inside these access networks and deliver content directly over the internal private address realms of the access networks. From this perspective, IPv6 is the 'Plan B' of network evolution. It's the fallback plan if, or when, the CDNs hit their own scaling issues that would be otherwise intractable.

On the other hand, there is the thread that is the continued IPv6 transition. It's not been easy. The IETF did go overboard to start, and this was unhelpful! Instead of standardizing just one dual-stack coexistence mechanism, or even just two, they came up with over thirty. And supporting dual stack coexistence is a real issue for network providers. For as long as there are important services that customers want to access or enterprise VPNs that rely on IPv4, then it's impossible for any mainstream access network to run an IPv6-only network that has no IPv4 services whatsoever, nor is it possible for equipment vendors, from mobile devices through to network infrastructure elements to sell a product that operates only in an all- IPv6 context. But if you have to support a dual-stack environment, then which transition mechanisms do you choose to support. For example, some mobile device platforms supported 464XLAT, while others opted for native dual-stack. Some supported IPv6 prefix delegation, while others supported DHCP6. With this diversity of device behaviors, what must the network do to support dual-stack environments? All of them?

Let's remember that this phase of the transition is not about switching to IPv6 but about adding IPv6 into the network and service environment. The supposed commentary is: "Yes, running two protocols is more complex and more expensive than one, but this is temporary, and once everyone gets to running two protocols, we can all turn off the older protocol and then life will be so much better in so many ways!" The problem is that not everyone feels the same pressures to embark upon this transition at the same time, so waiting for everyone to get a dual-stack environment up and running is taking us decades, and there is no end in sight. It's the laggards who control the overall timetable of this transition, and the costs of the protracted transition appear to be passed across to the early adopters of dual-stack services. For as long as this situation persists, then the collective impetus to complete this IPv6 transition process is not overly strong.

So how are we going with this transition to IPv6 in 2021?

Reviewing 2021 through IPv6 Glasses

Before looking at the current statistics for IPv6 deployment, I'd like to highlight two events that came to light in 2021 that I think are relevant, interesting milestones in the IPv6 transition saga.

The first is the state of the aftermarket for IPv4 addresses in 2021. The Internet has not stopped growing, and there is a continual flow of new entrants into the networking space that have a need for IPv4 addresses. The RIR-operated allocation mechanisms for IPv4 allocations have effectively exhausted themselves, so these new entrants are forced to use the aftermarket for IPv4 addresses. In all such markets, the key metric is the commodity price being traded.

Conventionally, the price reflects the effort of balance supply and demand. Excess supply saturates demand, and the price should fall, while insufficient supply causes competition between potential buyers and the price rises to the point where sufficient numbers of buyers are priced out of the market such that those buyers left in the market who are willing to pay the higher price can obtain supply.

However, in many markets, there is also substitution. Buyers will tolerate price escalation in a market as long as the market price remains lower than the cost of a substitute good. When the market price exceeds this substitution price, the market will be prone to flipping to a substitute good. Once the market has shifted and buyers have absorbed the transition cost, it is feasible that the adoption efficiencies of the substitute good cause the price of the substitute good to fall due to economies of scale. At the same time, the fall in demand for the original good would cause a collapse in the price of the original good, but if the market has shifted to rely on the substitute good, then the drop in price for the original good may not be enough to cause the market to revert in any case.

So, in this case, an escalating price for IPv4 addresses should make IPv6 a more attractive proposition. As the industry places more collective effort to complete this transition, the demand for IPv4 will collapse once a critical mass of clients and services are dual-stack capable, making an IPv6-only a viable service offering. At such a point, even though the price of IPv4 addresses may have collapsed, there is little remaining appetite to flip back to IPv4 because the costs of such a move back would far outweigh any short-term opportunity price signal about IPv4 addresses.

In other words, any price escalation has a ceiling, at which point the IPv4 address market will collapse completely, and such a market collapse will impact not only new entrants but existing address holders. It's not just market entrants and those wanting to acquire more IPv4 addresses who should pay careful attention to the price signals in the IPv4 address transfer market, but all IPv4 address holders and service providers who may be impacted by this rapid escalation in market prices if it leads to a subsequent collapse. At some point, it's possible for the market to enter a bubble phase, where the only players left in the market are speculators making short-term bets on how high the price can be driven before the inevitable collapse.

Figure 2 shows the timeline of the market price of IPv4 addresses, colored according to the prefix size of the traded block. The market price doubled across the period 2016-2019, from USD 10 per address to USD 20. In 2019 and the first half of 2020, the price was steady at around USD 22 per address. However, in 2021 it all changed again, and the price rose from USD 22 to up to USD 60 in just 12 months. The market also lost cohesion over the year, and in the latter half of 2021, there were transactions that completed with unit prices between USD 40 per address to USD 60. Perhaps the pandemic caused some interruptions in the flow of market information within the industry, and the result was price uncertainty and a far higher variation in the unit price paid in individual transactions.

What's behind this price rise? Panic? Or Scarcity? We can compare the data in Figure 2 against the total volume of address transfers that are registered in the RIR system (Figure 3). Based on the RIRs' transfer logs, the total volume of traded addresses dropped by some 40% in 2021 compared to 2020 levels. Presumably, the combination of declining volume and escalating price points to a scarcity issue with the supply of IPv4 addresses for trading.

If a relatively steady IPv4 trading price indicates some common level of confidence that the IPv4 market will continue to meet the aggregate demands from the sector for some years to come, then a sharply escalating price indicates an abrupt drop in that level of confidence. And if there is no confidence in the continued supply of IPv4 addresses, then that leaves IPv6 as the only Layer 3 response left.

It is also intriguing to observe that most of the transfers occurred in Europe and the Middle East region that is served by the RIPE NCC, while the transfer volumes registered in the North American region served by ARIN remain at an extremely low level.

The second event I want to touch upon briefly is the case of Slack's September 2021 outage. Slack is a cloud-based online collaboration application directed at the enterprise market. The exact details behind the incident are not that relevant here, but the point I want to highlight is that within the unfortunate combination of conditions that caused this outage, one of the contributory factors is that Slack is only supported on IPv4. Now, this is not due to Slack per se. Slack uses Amazon's AWS platform, and the story about IPv6 support within Amazon's AWS platform is an ongoing 'under construction' story. Why hasn't one of the major cloud platforms that supports enterprise applications been running IPv6 for the past decade or more? The answer is that they never felt under sufficient pressure from their customers to do so. The distributed enterprise world is still a landscape that appears to be largely shaped by IPv4, with scant use of IPv6.

What we appear to be seeing is a two-speed Internet, where one speed is determined by the large mass-market retail services that are slowly but surely heading down a path of dual stack adoption, driven largely by the escalating price of IPv4 addresses and the inabilities to push the NAT model even harder. This will remain the case while the major CDNs continue to live just outside the large retail access network's infrastructure. That gap between the access network edge and the CDN point of presence needs to be filled with public addresses, and this is the point of pressure for continued use of IPv4 addresses. The other speed appears to be determined by the enterprise sector. They, too, have been transitioning, but in that case, it's a transition away from dedicated IT services and fully owned and operated service platforms into cloud-based infrastructure. It's a long process hampered by capital, available expertise, and risk aversion. It appears that for many, the approach to this transition is to limit the extent of the changes at any one time, and here it's a case of keeping IPv4 as the mainstay of their environment as they move into a cloud-based environment. This manifests itself in many different ways, and a good example is Slack's use of an IPv4-only Amazon cloud platform, which makes sense for Slack only if you consider the preferences of their enterprise customers.

It appears that the underlying factors in 2021 were an unexpected and steep escalating of the market price for transferred IPv4 addresses and a continuing reluctance of the enterprise sector to make any visible moves to embrace a dual-stack environment in their IT platforms. Let's now look through some IPv6 adoption data to tell us more about what happened in 2021.

IPv6 Address Allocations

Figure 4 shows the number of IPv6 allocation per year from the RIRs. The allocation numbers are down from the high point in 2019 and these numbers have been constant at 5,400 allocations per year over 2020 and 2021. The level of allocations by the RIPE NCC has increased considerably, while the activity in LACNIC has declined by much the same amount when we look at 2020 and 2021. These numbers probably correlate with the various waves of larger lockdowns caused by the successive waves of the COVID-19 pandemic, which no doubt impacted the timing of infrastructure deployment plans for regional service providers as they occurred.

The volume of IPv6 addresses tells a slightly different story, and the amount of IPv6 addresses allocated or assigned by ARIN has declined considerably in 2021 over 2020 levels, while the year-on-year volume has doubled for RIPE NCC IPv6 allocations in 2021. The RIRs passed out a total of the equivalent of some 29,000 IPv6 /32's in 2021, an increase of 30% over 2020.

In the case of the RIPE NCC, most IPv6 allocations are /29 prefixes, and in 2019 they performed 2,499 such allocations; in 2020, just 933 and in 2021, the number was back to 2,499 allocations. APNIC's total allocation volumes are dominated by very large allocations and in each of the three years 2019 - 2021 APNIC allocated at least on /20 block (two in 2021) and either a /21 or a /22 as well. In ARIN's case,/20 blocks were allocated in 2019 and 2020. The total count of IPv6 allocated addresses has two components, namely a large volume of 'commonly allocated' address blocks (/29's in the case of the RIPE NCC and /32's in the case of the other RIRs) and a far smaller volume of very large address blocks (/21's or larger).

Routing IPv6

If we follow these addresses from allocation to routing, then the next view of the past year in IPv6 is the growth in size of the IPv6 routing table.

The long-term trend in the growth of the IPv6 network (Figure 6) is clearly one that is increasing over time. A reasonable fit for this data is an exponential growth model with a doubling factor of 24 months. A more detailed view of just 2021 is shown in Figure 7.

There have been some anomalies in the IPv6 routing table in 2021, with distinct jumps in the number of visible prefixes in April, May, November, and December.

Some 4,000 IPv6 announcements were added at the start of April 2021, and a further 5,000 announcements in mid-May. In both cases, these were predominately more-specific announcements, and in both cases,/48 and /32 announcements dominated. A similar situation occurred in November and December, where a collection of some 7,000 more specifics were announced in mid-November and then withdrawn in mid-December.

Routing advertisements of /48s are the most prevalent prefix size in the IPv6 routing table at the end of 2021, and some 47% of all prefixes are /48's. The next most common prefix size is /32, and these account for some 14% of all prefixes. Some 60% of the routing table are now more specific announcements of covering aggregate announcements.

Why is the IPv6 routing table being fragmented so extensively? The conventional response is that this is due to the use of more specific route entries to perform traffic engineering. However, this rationale probably does not apply in all cases. Another possible reason is the use of more specifics to counter efforts of route hijacking. This also has issues, given that it appears that most networks appear to accept a /64 prefix, and the most common disaggregated prefix is typically a /48, so as a countermeasure for more specific route hijacks a /48 may not be all that effective in any case.

This brings up the related topic of the minimum accepted route object size. The common convention in IPv4 is that a /24 prefix advertisement is the smallest address block will propagate across the entire IPv4 default-free zone. If a /24 is the minimum accepted route prefix size in IPv4, what is the comparable size in IPv6? There is no common consensus position here, and the default is to use no minimum size filter. In theory, that would imply that a /128 would be accepted across the entire IPv6 default-free zone, but a more pragmatic observation is that a /32 would be assuredly accepted by all networks, and it appears that most network operators believe that a /48 is also generally accepted. However, we also see prefixes smaller in size than a /48 in the routing table with /49, /52, /56 and /64 prefixes also present in the IPv6 eBGP routing table. Slightly more than 1% of all advertised prefixes are more specific than a /48, although it is unclear as to the extent of propagation of these smaller prefixes across the IPv6 BGP network.

Notably, some 4,000 ASes were added to the IPv6 network on the 20th of May. This appears to be a research platform being constructed by China's Education and Research Network, which has organized its route advertisements to advertise a single /32 IPv6 prefix per AS, using the block of AS numbers AS142650 - AS146745 for this purpose. Presumably, this is to support some form of network slicing research experiment, although it is unclear to me why these /32 advertisements are separately advertised into the global IPv6 routing table.

In better news, the stability and performance of the IPv6 routing system appears to be improving. This may be an unintended side effect of the pandemic, or more likely; this may be a sign that we are paying more attention to IPv6 routing than previously. The daily average of the time for the IPv6 routing system to converge to a stable state after a prefix update is shown in Figure 8. It has been steadily improving over 2021 from 120 seconds to 20 seconds.

Figure 8: Daily average IPv6 route convergence time 2020-2021

It is unlikely that this is a general improvement. The general characteristics of route updates are bimodal, where a small number of highly unstable prefixes are extremely unstable, while more prefixes are updated rarely and converge quickly. It is likely that what we are seeing across 2021 is the effort to remove the sources of pathological update behavior in the small number of highly unstable prefixes, exposing the baseline behavior of the more stable set of IPv6 routes.

This highly stable state observed at the end of 2021 is unlikely to continue, unfortunately. Concentrated points of instability in the IPv6 network continue to be a feature of the IPv6 network, where 1 or 2 networks are associated with half of the total updates observed in the IPv6 network.

Using IPv6

Next, we'll look at the ratio of users who demonstrate a capability to retrieve a web object over IPv6 as an indicator of the level of IPv6 adoption in the consumer Internet.

Figure 9 shows the time series of this measurement from the start of 2012 until early 2022. At present, some 31% of the Internet's user base is IPv6-capable, a rise of 4% over the previous 12 months.

Figure 9: Use of IPv6, 2012-2022

Obviously, this 30% count is not uniformly distributed across the Internet, and a map of where these IPv6 users are located is shown in Figure 10.

Figure 10: Distribution of IPv6 deployment, January 2022

Clearly, the adoption of IPv6 is highly varied. While there is a high adoption rate in India (76% of users), there are only five other economies where the IPv6 adoption rate is over 50% of users (Belgium, Malaysia, Germany, Viet Nam and Greece).

Where was IPv6 deployed in 2021? If we look at IPv6 deployment as a percentage of each national population and compare the measurement at the start of 2021 to that of the end of the year we can provide a list of economies that have the highest change in that ratio of IPv6 users. This is shown in Table 1.

The other way to generate this ranking is to use the estimated population of those users who are using IPv6 and the change in this count across 2021. This is shown in Table 2. While China ranked at position 5 in the relative ranking with a 13% annual change, with an estimated 820M users in China, this 13% change represents a change of 109M users. Similarly, India's change in 2021 was some 3% of its user base, which places it at 37th position in this ranking in relative terms, but this represents an additional 19M users, which is the second-highest count for 2021.

While the total data in Figure 9 shows a relatively modest growth for 2021 of around 4%, this corresponds to a further 171M users who are using IPv6, which is a considerable achievement.

There are two further areas of IPv6 deployment that should be mentioned, but they are far harder to measure.

The first area is the enterprise sector. This sector has been relatively conservative in its approach to new technologies and has relied extensively on private network platforms. This has meant that it has largely been isolated from the brunt of the issues with IPv4 address exhaustion and has been able to continue with an IPv4 agenda for the past decade. This sector has been moving to cloud services, but for many years these enterprise cloud services were able to operate on IPv4. It has only been in the past couple of years that we've seen announcements from Microsoft's Azure or Amazon's AWS that their platforms are introducing support for IPv6, and this appears to some growing awareness in the enterprise sector that they need to embark on their own dual-stack transition at this time.

The second area is the very reason why we opted to use a very large address field in IPv6, namely the Internet of Things (IoT). Estimates vary as to how many devices are out there in this network, probably because it's a space that defies most conventional forms of simple counting, but we use numbers between 20 billion and 50 billion when we talk to each other about the count of such devices. This was thought to be the so-called killer app for IPv6, yet it does not appear to have happened yet. Many of these devices hide behind intermittent connectivity, and so far, IPv4 and NATs appear to be capable of servicing such requirements with some ease. However, perhaps this is like the enterprise market and is more of a case of a slow start. There are many issues with the IoT, not the least of which is the dubious resilience of these devices and their evident inability to resist being co-opted into zombie attack armies of truly massive proportions. While we are constantly reminded that NATs are not a robust security defense, NATs are often used as such. The prospect of having all these unmanaged, ignored and potentially highly vulnerable IoT platforms being placed online in an always-on IPv6 scenario is truly scary! We really should figure out a much more robust approach to the IoT world before we flick on the IPv6 switch and expose all these built-to-the lowest-possible-budget devices to the toxic underworld of direct Internet connectivity! In the meantime, perhaps it's a good thing that most of these devices hide behind NATs!

2021 in Review

At first glance, it may have looked that 2021 was another year of locking down in the face of the continued COVID-19 pandemic, but there was still much that was going on in IPv6 deployment and the dual-stack transitional Internet.

There is further scarcity pressure on IPv4 addresses, reflected in price escalation in the transfer markets. The IPv6 routing system is getting more operator attention, and the IPv6 network is proving in stability and performance. The consumer sector is continuing its expansion of IPv6 both in the major markets of China and India, as well as in numerically smaller markets such as El Salvador and Nepal. And we are seeing signs of movement in the enterprise sector.

Does all this mean that there is some end in sight for the protracted IPv6 transition? Are we finally getting somewhere with IPv6? Will the remaining two-thirds of the Internet be easier and faster to push through this transitional phase, given our experience with the first third of the Internet? Maybe, at the start of 2022, there are some grounds to be a little more optimistic than we were a year ago in attempting to answer this question.

Personally, however, I'm not convinced that this is the case, and I'm not optimistic about a hastened end to this transition process.

Much of the Internet's evolution over the past decade has been in making the entire issue of static IP addresses irrelevant to the overall architecture of the Internet. We don't necessarily want to head back to a 1980s network architecture where the overloaded identity and location semantics of IP addresses presented some real limitations to the flexibility of the network. We are heading down a path that strips most of the semantic loading from IP addresses and places those functions into the Internet's name system.

It may well be the case that if we ever get close to the end of this transition, we might look around at that time and realize that it just doesn't matter anymore! By that time, we might be ready to consign the entire framework of a coherent address infrastructure into a completed but abandoned chapter in the history of the evolution of networking technology.

But perhaps I am being overly premature in anticipating the end of this transition. Right now, we seem to have grown used to a world that is in perpetual transition, and it seems to be far harder now, at the start of 2022, to predict when this transition process will be resolved one way or the other than when we chose to head down this path in 1995!

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I bet that nobody believed in 1992 that thirty years later, we'd still be discussing the state of the transition to IPv6!

# data[].attributes.body
Summary:
The IPv4 address space has been excused which has been partly caused by internet of things. It is going to be hard to switch to IPv6 as many devices do not support it so they will have to be replaced. But with IPv6, we will not have to worry about address space issues

Reflection:
I agree that the switch to IPv6 is going to be tough especially for legacy devices and internet infrastructure . This is going to require many device replacements and some things will probably stop working when they used to work perfectly. But this is what is going to have to happen to fix the IPv4 address crisis the correct way.

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Every business realises the need to remain flexible. Adapting to new situations is crucial to stay afloat. That's why we should ask ourselves: is it finally time to move to IPv6 addressing?

If you're not sure what I'm talking about, I'll get right to the explanation. Every device connected to the internet receives an IP address, which acts as its ID. The current standard is called IPv4, and is based on a 32-bit system, giving us roughly 4 billion total available IP addresses. That seems like plenty, right?

Not quite.

Even at this point, Gartner predicts that around 8.4 billion Internet of Things devices are connected. And every single one of them requires an address. IPv6 uses a 128-bit format rather than 32, resulting in as many as 340 trillion combinations. Now, that will take a moment to exhaust, and fortunately we've already gotten started on using them. However, not every company and private network managed to proceed with introducing the new standard.

So what reasons are there to introduce your company to IPv6?

Migrating to the new system has several benefits. First of all, it handles packets more efficiently, resulting in not only better performance, but also increased security. As opposed to IPv4, IPv6 does not contain a checksum which needs to be calculated at every step, and instead uses the time to route packets.

IPv6 also makes use of multicast transmission instead of its predecessor's broadcast version. Bandwidth-intensive traffic can be simultaneously sent to multiple client destinations. Only the ones who previously opted-in for receiving the packets will process them, reducing traffic in a local network and reducing congestion overall.

Latest standard also allows to be connected to several networks simultaneously, by allowing the IT staff to assign several addresses to the same devices thanks to increased configuration possibilities. Its configuration is also significantly simplified due to automatic client-side IP address assignment included in it, instead of utilizing a DHCP server as in IPv4.

IPv6 is also much more secure than its previous iteration, which was invented back in 1983, before the internet, WiFi, or even home networks were created. It includes packet protection and encryption similar to that utilized by VPNs, even in case of normal internet traffic. This enormously diminishes the possibility that they will be intercepted, improving the network's security.

What challenges will we face while transitioning?

However, like with every technology, transferring to IPv6 will not be easy. At this moment, not every network device supports it, requiring us to update most of our hardware. This includes things like routers, switches and access points, but also our operating systems, smartphones and laptops. Many of them will need to be capable of handling both IPv4 and IPv6 for some time, in order to ensure a smooth transition from one to another. Since the standards are not designed to be interchangeable, the devices that are set to work with only one of them will progressively lose connectivity with others as they develop.

Documentation changes, staff trainings, and software adaptation will be required on top of that, which means that for larger corporations it might take even several years to conduct the change. Solutions that are based on VOIP or IoT will also need to be adjusted accordingly in order to not restrict their potential customer base. Regardless whether they do it right now, one thing is clear - it will be absolutely necessary in the near future.

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Should We Begin To Consider Switching To IPv6?

# data[].attributes.attachment_link.description
Every business realises the need to remain flexible. Adapting to new situations is crucial to stay afloat. That's why we should ask ourselves: is it finally time to move to IPv6 addressing? If you're not sure what I'm talking about, I'll get right to the explanation.

# data[].attributes.body
Summary:
We are going to have to move to IPv6 in the future, but this will be tough. One reason is IT departments will have to learn a new protocol that is not at all like IPv4 even though many think that it is.

Reflection:
IPv6 introduces some new features and removes other features previous used in IPv4. This add complexities for companies IT department as subnetting, NAT, and DCHP are all totally different in IPv6. This will require learning about IPv6 and then implementing it. With all this time devoted to IPv6, it starts to sound very expensive to companies, which might make them hesitant to switch until it is necessary.

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Today is the beginning of the end of the Internet as we know it.

That's because the rules that govern how data is sent across the Net, a standard called Internet Protocol version 4, just became significantly more obsolete. The central Net authorities just handed out the last batches of IPv4 addresses at a ceremony today in Florida, beginning the cascade of scarcity that eventually will mean the computing industry must make the painful transition to the newer but incompatible IPv6.

It's not an urgent problem for average consumers with broadband or even for many businesses with lots of servers. But it is a problem of unprecedented magnitude since ultimately it involves anything that touches the Internet, from the lowliest smartphone to the most powerful router shuttling data packets.

"This is the first definitive sign we are going to have a completion of IPv4. We've run out of the pool at the central level," said John Curran, chief executive of the American Registry for Internet Numbers (ARIN), a group that received one of the last batches of IPv4 addresses. "It doesn't mean there are no IPv4 addresses available. This is not the absolute end, but this is the definitive point where people know that we are indeed going to run out of IPv4 addresses and that they need to begin the planning for how to operate their businesses without receiving additional IPv4 addresses."

Consequently, a lot of changes will arrive in coming days, months, and years. Here's a look at what's happening as the tech industry grapples with IPv4 exhaustion and the transition to IPv6.

What is an IP address?
An Internet Protocol address is simply a big number that identifies a computer on the Internet. Packets of data sent across the Net include the destination address. When you send an e-mail or watch an online video, any number of computers, switches, routers, and other devices scrutinize the IP address on these packets and forward them along to their eventual destination.

IPv4 addresses are 32-bit numbers, meaning that there are 4.3 billion possible addresses. IPv6 addresses are 128-bit numbers, meaning that the number of possible addresses soars vastly higher to 340,282,366,920,938,463,463,374,607,431,768,211,456, or 340 undecillion for short.

The first big problem with the change from IPv4 to IPv6 is that one variety of IP data can't travel on a network set up to handle the other variety. That means, for example, that a home computer and Internet service provider using IPv4 can't easily reach a Web server using IPv6, or a mobile phone connected to the Net with IPv6 can't reach a Web server available only over IPv4.

The second big problem is that even though IPv6 was standardized more than a decade ago, there hasn't a strong incentive for IPv6 upgrades. Why should Web sites pay for new hardware, software, network equipment, and testing if almost nobody is using IPv6 yet? And why should people switch to IPv6 if there are no Web sites with IPv6 content? It's the IPv4 exhaustion that's finally providing the necessary incentive. There were some nice new features such as built-in secure networking that could have attracted people to IPv6 faster, but "everything that was really useful, people backported to IPv4," said John Heideman, who studies networks at the University of Southern California.

Isn't 4.3 billion an awful lot of IPv4 addresses?
It is, but the way the Internet is structured today, it's not enough.

Vint Cerf, now an Internet evangelist at Google, picked the 32-bit address space decades ago when the Internet was a mere experiment. In an interview earlier this year, he said, "Who the hell knew how much address space we needed?"

In the Net's early days, vast tracts of this address space were handed out to those who showed interest--IBM, Stanford University, and AT&T's Bell Laboratories, for example. In the 1990s, a more conservationist approach arrived, but the Net being a foundation now for so much commerce, education, government, entertainment, and communication, addresses are still being consumed fast.

The IPv4 space is divided into 256 sections. Each one, called a /8 or slash-eight, has 16.8 million IP addresses. But while 84 million addresses may seem like a lot, the world consumed 319 million IP addresses in this way last year. And though many organizations have more IPv4 addresses than they need, it's not a trivial matter to reassign them to another party; it may requires extensive network updates that assign thousands of devices new numbers to free up an uncluttered expanse, for example.

Here's a revealing statistic about how efficiently the IPv4 address space is used, though. Heideman, who regularly surveys the entire IPv4 Internet through an exhaustive two-month census, just announced his latest findings: "Maybe 14 percent of the addresses are actually in use."

Full utilization is unrealistic, since some wiggle room to deal with changes is necessary, but, he said, "14 percent seems low. We probably could easily do twice that." Here's the catch, though: it's not free to shuffle IP addresses around, especially to do so dynamically to account for changing demand. "The challenge is the higher and higher we push utilization, the greater overhead there is to manage that space," Heideman said. "It's important to weigh that against doing something like IPv6 where management becomes very easy."

Unfortunately, given the hardware already installed today, there's no graceful way that IPv6 could have been engineered for a more graceful transition. When moving an address space from 32 bits to 128 bits, "that's something you cannot graft on," said Asif Hazarika, senior product manager for network operating system maker IP Infusion.

Who's running this show anyway?
Brace yourself for some bureaucracy-flavored alphabet soup. Here goes:

At the highest level, the Internet Corporation For Assigned Names and Numbers (ICANN), a non-profit group set up in the 1990s by the U.S. Department of Commerce, governs the Internet's inner workings. An ICANN group called Internet Assigned Numbers Authority (IANA) holds the central supply of IPv4 addresses. As demand arrives, IANA hands out /8s to five more non-profits called regional Internet registries (RIRs), each of which handles a different geographic domain in the world and which belongs to a group called the Number Resource Organization (NRO).

All these groups are Webcasting a press conference and ceremony today to mark IANA's allocation of the last five /8s. Under pre-established rules, each of five RIRs gets one /8 apiece, and the move was triggered when the Asia-Pacific region's RIR snapped up two blocks of IPv4 addresses.

Once an RIR has a batch of IP addresses, it leases them out to companies such as Internet service providers and mobile phone network operators. ISPs and Web hosting companies, in turn, offer IP addresses as part of their services to customers that need to put their computers on the Net. Sometimes ISPs and carriers assign IP addresses dynamically, pulling one from the pot as needed when home routers or smart phones attach to the Net. Sometimes IP addresses are permanently assigned, as in the case of servers that need a fixed address for reliable Web access.

When will we really run out of IPv4 addresses?
Even though IANA is handing out the last batches of IPv4 addresses now, it'll be a while before they actually come close to running out. "In ARIN, we expect six to nine months before we don't have addresses generally available for signup," said ARIN's Curran, who runs the RIR for the United States and Canada. Then it'll take some more time for the ISPs to run through their supply.

So although supplies are tightening now, it's likely there will be IPv4 addresses still available at the retail level in 2012. As they get scarcer, though, expect the price of an IPv4 address to go up--at least until the IPv6 transition is mostly over and done with.

The problem varies according to what your needs are. A company with a few Web servers doesn't need many externally facing IP addresses, and internal networks aren't generally affected by the IPv4 shortage. A major wireless carrier has a bigger problem on its hands, with a burgeoning customer base using smartphones to check e-mail, play networked games, and post Facebook status updates. And large ISPs that offer Net access to millions of homes and businesses are likewise constrained.

What about all those companies with millions of extra IPv4 addresses?
Some that got IPv4 addresses for free, including Stanford, BBN, Interop, and the Defense Department, have voluntarily returned IP addresses they don't need. But there are lot more organizations that arguably don't, and it's up to them to decide what to do. Among those with a /8's worth of IPv4 addresses are the U.S. Postal Service, airline operations support company SITA, Prudential Securities, pharmaceutical giants Merck and Eli Lilly, the Massachusetts Institute of Technology, IBM, Apple, Xerox, AT&T, Level 3 Communications, General Electric, Ford Motor, and Halliburton.

Part of Curran's job at ARIN is to call such companies and tell them, "You have address space. You're not using it. If you can return it, you should," Curran said. "But I also say in same breath, there will be demand for these. If you hold onto them, you may decide to monetize them."

In the early days of the Internet, addresses were allocated in only three sizes: /8 chunks with 16.7 million addresses, /16 chunks with 65,536, and /24 chunks with 256. "For any sizable corporation or university getting involved, it was really easy to explain that 64,000 was not enough. So you'd get the next block up, 16 million," Curran said. In the 1990s, a new system arrived called Classless Inter-Domain Routing (CIDR) that permitted much finer gradations of allocation, but not before many /8s were out of circulation.

Can't we use NAT to get out of this bind?
Network address translation, or NAT, lets a group of computers share the same publicly visible IP address, and if you have more than one computer or phone attached to your home wireless network, you're almost certainly using it there. A variation called carrier-grade NAT operates similarly but at a higher level, a whole Internet service provider.

There are problems with NAT, though. It's tough to set up peer-to-peer connections; intermediate routing devices introduce complexity, points of failure, and communication delays; and NAT can obscure useful information such as the general physical location of a person on the Internet who might want local services. And though it can extend IPv4's useful lifespan, it comes with management expenses of its own--especially for ISPs and carriers managing large numbers of devices connecting to the Net.

"In the long term, connecting millions of subscribers with IPv4 becomes an exercise in diminishing returns," Curran said.

What does the average person have to do?
Not much--at least initially.

Most reasonably modern hardware is OK. Versions of Windows since Windows XP Service Pack 1 can handle IPv6. Mac OS X has had support since version 10.2. New iPhones and Android phones are likewise equipped, and Verizon is requiring any phones using the LTE version of 4G networks to have IPv6 support. The bigger problem comes with home networking products. In order to get an IPv6 connection to the Internet, people need an IPv6-capable cable or DSL modem and wireless router. Those are the exception rather than the rule today in electronics stores, in part because ISPs don't usually offer IPv6 support in the first place.

So initially, it'll be business as usual for the average person. In all likelihood, ISPs will start adding new capacity with IPv6 and supplying compatible network gear to new customers. Upgrading likely will take place later, but the details are fuzzy so far. "We have not yet developed our business plans for how to get customers IPv6-capable cable modems," said Jason Livingood, executive director for product platform engineering at Comcast, one of the largest ISPs.

Having IPv6 customers will pose some problems, since an IPv4-only server has no way to talk to computer with an IPv6 address. Thus the preferred solution will be a "dual-stack" approach in which a computer speaks either IPv4 or IPv6 as necessary. "Native dual stack is superior to tunneling or doing one or more NATs in the network; direct, native access is faster and does not break certain applications, therefore resulting in a better end-user experience.

Will the Net break because of this?
No, though some hiccups and slowdowns are possible.

That's because there will be strategies such as proxies, translation, and tunnels to help IPv4 and IPv6 get along. For example, a person at home whose ISP assigned an IPv4 address, could try to reach an IPv4-based Web site. But the route in between might require IPv6, in which case hardware would have to wrap up the IPv4 data in IPv6, deliver it to the other side, then unwrap it for delivery to the other computer. That would have to be repeated for each packet of data sent in either direction, slowing network performance and increasing complexity.

Or take the case of an IPv6 phone trying to reach an IPv4 service on the Net. "These IPv6 phones have no way to contact the rest of the Internet on IPv4 unless you put a proxy in there. As soon as you do, you have a lot of overhead," said David Siegel, vice president of IP services product management at network expert Global Crossing.

What about all those "reserved for future use" IPv4 addresses
If you look at end of the IANA list of IPv4 allocations, you'll see 16 /8s--that's a sixteenth of the entire IPv4 address space--that are reserved for "future use." This might be a good time use use them, right?

Alas, wrong. Those addresses were reserved when the Internet Engineering Task Force (IETF) set up a standard for IP multicast, a technology to broadcast data to many recipients across the Internet. With multicast, a content provider sends data to a particular "rendezvous" IP address, and recipients listen for packets sent to that address. That means that a TV station sending data to 1,000 watchers only needs to send one stream of data rather than 1,000. When the IETF set up the standard, it set aside 16 /8s for some future version of the technology that thus far never was used. The standard was baked into network routing hardware, though, meaning it can't be used for other purposes now, IETF Chairman Russ Housley told CNET:

The address blocks at the end of the address range were set aside for multicast in 1989. Within the multicast addresses, 240/8 through 255/8 were set aside for future approaches to multicast. However, all Internet routers know that 224/8 and above are multicast addresses, so they cannot be repurposed as traditional IPv4 addresses. If this were a viable way to avoid the IPv4 address space exhaustion, it would have been done a decade or more ago.

How long will it take companies to move to IPv6?
For customers Global Crossing is helping with the transition, the answer ranges from a couple months to years, Siegel said.

It's not as hard for companies that don't have many operations visible over the public Internet and don't have a big appetite for new IPv4 addresses. Carriers and ISPs, with a greater constraint on IPv4 addresses, have to move faster. "We're seeing mobile phone use and broadband deployments to the home being big drivers" for IPv4 demand, Curran said.

There are plenty of hurdles in the way. IPv6 is simply not as mature as IPv4 when it comes to product support, and people aren't as familiar with factors such as new network security options. Hardware and software support for IPv6 has been coming for ages--router maker Juniper Networks first added support in 2001, and networking rival Brocade did so then, too, for example. But it's not always complete support.

"One customer in the media and entertainment industry has been in the process for over a year," Siegel said. But their Cisco routers, while supporting IPv6 at the high level, can't do some tasks such as helping to balance network loads across many servers or using Cisco's proprietary IEDRP--Enhanced Interior Gateway Routing Protocol--to route data around the network, he said. "Their whole IPv6 installation has stalled. We're back at the vendor trying to get these feature requests bumped in priority so the customer can implement IPv6. Until that time, they have two choices. They either don't implement it, or they remove features from their network that are currently supported [with IPv4]."

The earliest IPv6 adopters that Brocade has seen are content delivery networks such as Limelight Networks, which announced IPv6 support last year for its technology to distribute customers' data across the global Internet, said Ken Cheng, vice president, service provider products at Brocade. Those CDN companies could become more important since they can provide an easy way for companies that lack IPv6 support on their Web sites to get it. Essentially, it would become the CDN company's problem.

Google and Facebook have relatively aggressive IPv6 migration plans, with services available over the next-gen network today, and Yahoo plans to start making its move later this year. Those companies will help iron out expected IPv6 bugs on June 8 during an event called World IPv6 Day. Though many others offer some IPv6 services, today it's relatively unusual for Web companies. Often it's complicated to add, requiring a new IPv6-facing front end to run alongside the older IPv4 servers.

Even though many people don't need to have IPv6 up and running immediately, there's no time like the present to get cracking, Siegel said. "Everyone responsible for managing an Internet network should make a commitment, rip the Band-Aid off, start planning the migration, and just do it."

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Moving to IPv6: Now for the hard part (FAQ)

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Today is the beginning of the end of the Internet as we know it. That's because the rules that govern how data is sent across the Net, a standard called Internet Protocol version 4, just became significantly more obsolete.