Tag: IPv4

IPv4 Exhaustion Gets Real – Microsoft Runs Out Of U.S. Addresses For Azure Cloud – Time To Move To IPv6!

us ipv4BOOM! IPv4 address exhaustion just hit home really hard for a good number of people.  They set up virtual machines (VMs) in a US region on Microsoft’s Azure Cloud and now suddenly find that when they use those VMs to access other websites they are treated as if they are from a country outside the US.  Why?

Because Microsoft RAN OUT OF IPv4 ADDRESSES from its “U.S.” blocks of IPv4 addresses!

As Microsoft notes in their blog post:

Some Azure customers may have noticed that for a VM deployed in a US region, when they launch a localized page on a web browser it may redirect them to an international site. 


They go on to say precisely what we and many others have been warning about for some time:

IPv4 address space has been fully assigned in the United States, meaning there is no additional IPv4 address space available. This requires Microsoft to use the IPv4 address space available to us globally for the addressing of new services. The result is that we will have to use IPv4 address space assigned to a non-US region to address services which may be in a US region.  It is not possible to transfer registration because the IP space is allocated to the registration authorities by Internet Assigned Numbers Authority.

Keep in mind, too, that back in 2011 Microsoft bought 666,624 IPv4 addresses from Nortel for $7.5 million. So they have already been shopping for more IPv4 space in the North American region.

They’re out.  Done.  Finished.

And so all those people wanting to run VMs on Microsoft’s Azure Cloud are suddenly confronting the reality that if they wanted their server to appear as if it came from the US, they can’t!

Sure, their domain name can look like it is a regular address for a US company… but in the underlying IP addressing their server will appear to the rest of the Internet to be in Brazil or some other location based on some of the geographical IP databases.

UPDATE: It is apparently not just Azure Cloud accounts in the US.  Over on Hacker News a commenter indicated that an Azure account in the North Europe datacenter in Dublin, Ireland, is also getting an IP address from Brazil.  I would guess (but don’t know for a fact) that this means Microsoft may be out of European IP addresses, too.

The impact is that servers running in the Azure Cloud (on VMs) may be treated by applications and services running on other servers as if they are outside the U.S. and so they may be given different choices or options than would be given to US servers.  The example shown in Microsoft’s blog post is of a web browser running on a VM connecting to a site and being given a Portuguese web page because the web server thought the incoming connection was coming from Brazil.  Depending upon how strongly the web server being visited serves out pages based on geographic IP data there may or may not be an easy option to get to pages intended for visitors from the US – or it might at least require more steps.   On a more serious note, there may be some sites that might block traffic in their firewalls based on where IP addresses are thought to be coming from – and so while you thought your server was set up “in the U.S.” it could instead wind up on someone’s blocked list.

Somewhat ironically, we wrote just yesterday about the need for cloud providers to get with the IPv6 program - and today we have living proof of WHY cloud providers need to care.

And as we also noted earlier this week, Latin and South America are basically out of IPv4 addresses – so while Microsoft can use some Brazilian IPv4 addresses today, odds are pretty good they won’t be able to get any more!

Here are a couple of other posts about today’s news:

The cold hard reality is that we simply cannot continue to rely on the “experimental” version of the Internet that used IPv4 addresses.  We need to collectively take the leap to the production version of the Internet using IPv6.

There are BILLIONS of people still to come online on the Internet – and there are BILLIONS more devices that we want to put online as part of the “Internet of Things”.  IPv4 simply doesn’t have the necessary number of addresses!

To get started with IPv6, please visit our “Start Here” page to find resources that are focused for your type of organization. And if you don’t find what you need, please let us know!  We are here to help you make the transition!

As Microsoft so vividly showed us today, IPv4 exhaustion is going to increasingly make IT systems more complicated.  It’s time to make the move to IPv6 where we don’t have to worry about address exhaustion – or having to use IP addresses from a different part of the world.

The time for IPv6 is now!

Good discussions on this topic are happening at:


Goodbye, IPv4! IANA Starts Allocating Final Address Blocks

ICANN.jpgIPv4 address exhaustion just got more real! In an announcement on Tuesday, the Internet Corporation for Assigned Names and Numbers (ICANN) indicated that they are starting the process of allocating the final available blocks of IPv4 addresses out to the Regional Internet Registries (RIRs) from the IANA recovered address pool. (ICANN is the operator of IANA.) As the announcement states:

ICANN announced today that it has begun the process of allocating the remaining blocks of Internet Protocol version 4 (IPv4) addresses to the five Regional Internet Registries (RIR). The activation of this procedure was triggered when Latin America and Caribbean Network Information Centre’s (LACNIC) supply of addresses dropped to below 8 million.

This move signals that the global supply of IPv4 addresses is reaching a critical level. As more and more devices come online, the demand for IP addresses rises, and IPv4 is incapable of supplying enough addresses to facilitate this expansion. ICANN encourages network operators around the globe to adopt IPv6, which allows for the rapid growth of the Internet.

This is it, folks.

We’ve been talking for many years about IPv4 addresses running out.  Now it’s happening.

[NOTE: Back in February 2011, IANA allocated their final IPv4 address blocks from the "free pool" of IPv4 addresses.  IANA then worked with the five RIRs to recover unused IPv4 address blocks and establish the "recovered address pool". The agreement was that allocations would start from this pool when the first RIR hit its last /9 block of IPv4 addresses, which LACNIC recently did. After this recovered pool has been allocated to RIRs, there simply aren't any more IPv4 addresses for IANA to give out.]

Yes, there are enough IPv4 addresses in the overall system right now that we’re not running out of addresses TODAY … but we are basically OUT at the top-level.  The final allocations will occur over the next few months as part of the Global Policy for Post Exhaustion IPv4 Allocation Mechanisms by the IANA.

It will be increasingly hard for network operators to get more IPv4 addresses for new customers and new networks.

If you are not yet planning for a transition to IPv6, you really need to get going now! If you want to grow your network, the simplest and easiest path will be to make the move to IPv6.  Check out our “Start Here” pages to learn how you can get going!

DO YOU HAVE A GREAT EXAMPLE OF MOVING A NETWORK OR APPLICATION TO IPv6?  We are seeking IPv6 case studies for our upcoming celebration of the 2nd anniversary of World IPv6 Launch. If you have a great IPv6 story, we’d love to help share that story for others to learn from it. Please let us know.

UPDATE #1 - If you are interested in learning more about how IPv6 adoption is going, check out our list of IPv6 statistics sites.  In particular, look at the World IPv6 Launch measurements, where this month Verizon Wireless crossed over 50% IPv6 for the first time!

UPDATE #2 - There is an excellent discussion thread currently underway on Hacker News about this article.

UPDATE #3 – The Number Resource Organization (NRO) has a statement up on their website.

Time To Get IPv6! ARIN Starts Allocation From Its LAST Major Block Of IPv4 Addresses

ARIN logoSoooo… if you are in North America and have NOT started planning for a migration of your network to IPv6, now would be a REALLY good time to start doing so!  The news comes today from the American Registry for Internet Numbers (ARIN) that they have now started allocating IPv4 addresses from their last contiguous block of IPv4 addresses.

Now, this doesn’t mean that ARIN is out of IPv4 addresses… but it’s getting really close!  Per ARIN’s IPv4 Countdown Plan page, they only have 1.42 /8s left.  Basically, they have 104.x.x.x to allocate out to Internet service providers (ISPs) and then a number of other smaller ranges and then…

Boom.  That’s it!

There will be no more *new* IPv4 addresses available in the US, Canada and many Caribbean and North Atlantic islands.

Existing IPv4 addresses will continue to work just fine, of course, but any new networks or devices seeking to be connected to the public Internet are going to have to re-use existing IPv4 addresses via ugly NAT arrangements – or go IPv6.  So… mobile operators looking to expand and add on more devices.  All the companies looking to bring a zillion more appliances and devices onto the Internet via the “Internet of Things”.  Any expansions into new geographic areas.

We’ve been saying for years that we’d be running out IPv4 addresses… but now it’s actually happening in North America!  (and also in the European and Asia Pacific regions)

It’s time to get going with IPv6!  What are you waiting for?  And how can we help you?

What’s Wrong With This IPv4 Application?

See any problem with entering IPv6 addresses using this user interface? Probably not going to work to well, is it? 🙂

Iphone ipv4

This is just the network config interface of an IP phone I had on my desk. While some of you from the VoIP world might recognize the vendor, the truth is that most IP phone vendors’ apps have similar interfaces. These are the type of user interfaces I discuss in Chapter 1 of the book and that will be one of the biggest challenges for app developers. In the case of IP phones, the challenge is even greater because it is running on an embedded device using typically a special-purpose operating system.

Where do you have user interfaces like this lurking in your applications?