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IPv4 Address Crunch In 2 Years, IPv6 Not Ready

An anonymous reader writes "We've known for ages that IPv4 was going to run out of addresses — now, it's happening. IPv6 was going to save us — it isn't. The upcoming crisis will hit, perhaps as soon as 2010, but nobody can agree on what to do. The three options are all pretty scary. This article covers the background, and links to a presentation by Randy Bush (PDF) that shows the reality of the problem in stark detail."

22 of 539 comments (clear)

  1. Dupe by suso · · Score: 5, Informative

    Here is the story from a few weeks ago

    And as I said before, the solution is to take back some of those huge class A blocks from companies like HP, Ford and GE, which are not using all the space. That would buy a few years.

    1. Re:Dupe by Silver+Sloth · · Score: 4, Informative
      RTFA - which says

      ... there are ideas for managing the address space more efficiently by introducing auction and other pricing mechanisms to encourage better use (people who don't need their allocation will flog them off rather than hoarding them, while new uses will be parsimonious in their approach), but the developing world sees this as unfair in the extreme. You can see their point.

      There are other problems: how do you route IP addresses when the existing hierarchy breaks down due to address spaces moving through the network? Who's responsible for managing an increasingly incoherent network? Who foots the bill when your address space is sold from underneath you? In any case, it doesn't solve the basic problem - it merely makes it increasingly expensive to innovate. so it's not quite that easy...
      --
      init 11 - for when you need that edge.
  2. People are starting to work on solutions by Anonymous Coward · · Score: 5, Informative

    The basic solution to this problem is to deploy IPv6 as soon as you can, figure out what problems remain to be solved before you can use IPv6 100% and then put pressure on your ISPs, vendors, etc. to solve these problems. That's how the Internet grew like topsy in the first place, and its not too late to get this going. Two to three years is enough time.

    ARIN has published a web site which collects information about how to move to IPv6 here: http://www.getipv6.info/
    It's oriented towards the things that ISPs and other service providers (hosting centers, large IT depts) need to do to get IPv6 working in production.

    Soon, the stock market analysts will be asking the big ISPs and telecom companies what actions they are taking to avoid going bankrupt in two years when the crunch hits. Any company that can't get new IPv4 addresses will have to stop growing their IPv4 networks. If they have an IPv6 network to take up the slack, no problem. If not, then customers will flock to the providers that have IPv6 ready to roll.

    There was a network operator meeting at NANOG recently where they showed that it is almost possible to provide full Internet access, both IPv4 and IPV6, using an IPv6 connection. Yes, I know, "almost" means there were problems, but they were not massive problems. They were the kind of things that people were working on fixing with IPv4 networks back in the early 90's. And they did that because they went ahead and built IPv4 networks and tried to make them work for everything imaginable. When things broke, they fixed the bugs and moved on, eventually becoming the global Internet that we know today.

    There is a way to avoid going bust when the address crunch hits in two-to-three years and that is: Get yourself IPv6 Ready!

  3. SSL by mother_reincarnated · · Score: 3, Informative

    would it be feasible to host, for example, 100 different websites on one ip using header information? or does that have traffic spike issues/ latency issues/ wasted cycles involved? The real problem is https not http - you don't get the host header until well after you had to present a certificate to the browser. For http 100 'virtual host-by-name' sites on one IP wouldn't even break a sweat for a good setup.
  4. Three Things for Widespread IPV6 Acceptance: by JoeD · · Score: 5, Informative


    1. Home routers that support IPV6 off the shelf.

    2. Cable/DSL modems that support IPV6 off the shelf.

    3. (The biggie) ISPs that hand out IPV6 addresses.

    In a vain attempt to forestall the inevitable followups:

    Yes, I am aware that I could install new software in my WRT-54G, and convert my home network to IPV6. But as long as my upstream connection is IPV4, this gains me NOTHING except a bunch of aggravation and downtime getting the thing set up. No thanks. When my ISP supports IPV6, then and only then will it make sense for me to convert.

  5. Itojun by eldavojohn · · Score: 3, Informative

    Yeah, we always fall back on the government to help us out when us nerds aren't satisfied with how capitalism is driving the technological trends that need to happen.

    But let's not forget those that went before us. Jun-ichiro Hagino, better known as Itojun, was one of the first researchers that was pushing for IPv6 since as long as I can remember (at least 2001). On top of that he was developing specifications for it and working through the BSD code to make it one of the first operating systems fully capable of being IPv6 compliant--starting a trend that needs to happen in more operating systems sooner. He even started documenting draft APIs to get developers thinking about how this would work inside software.

    And then he died in a car accident at age 37. It's funny how you don't appreciate their work until they're dead. Almost like a painter or author.

    Although many still carry on his work, the saddest part is that all his efforts to bring awareness to everyone about IPv6 may fall into the responsibilities of the government or, worse, capitalism.

    --
    My work here is dung.
  6. Re:Is this REALLY a problem? by ModMeFlamebait · · Score: 5, Informative

    Except you can't NAT a NATted connection.
    Sure you can.
    --
    Pavlov. Does this name ring a bell?
  7. Re:Is this REALLY a problem? by Tranzistors · · Score: 5, Informative

    Last I heard, two NATted clients can't talk to each other.

    Unless you have port forwarding (or how do you kids call it these days)

  8. Re:Tell MIT and IBM by beuges · · Score: 3, Informative

    As a commenter above posted, each of those companies with top-level blocks actually owns 16,777,216 IP addresses. These companies include IBM, MIT, Ford, DEC, AT&T, Apple and Xerox.

    As big as IBM and MIT may be, do you really think they need almost 17 million IP addresses?

  9. Re:Is this REALLY a problem? by suggsjc · · Score: 3, Informative

    Except you can't NAT a NATted connection.
    Sure you can. All NAT does is take one IP address, monitor connections and spread/translate the unique connections across different ports. The device doing the NAT doesn't care "where" it gets its source IP from, it just knows that it has an IP and it splits the connections to that IP. The only potential issue is that if the first NAT runs out of available ports. However, at that point its routing table would be huge and it would probably begin to degrade in performance (depending on the hardware).
    --
    When I have a kid, I want to put him in one of those strollers for twins and then run around the mall looking frantic.
  10. Re:Tell MIT and IBM by gclef · · Score: 3, Informative

    God damn, I'm tired of fighting this meme. Look, as I mentioned in another response, we allocate 10-12 /8's every year, and that rate is increasing. Reclaiming MIT & IBM's /8's would buy us at approximately 2 months at our present allocation rate. The negotiation to make that allocation possible would take far longer. Reclaiming space is not a useful activity at this time.

  11. Re:Well duh by Anonymous Coward · · Score: 3, Informative

    you don't get to be president because you're Joe Average from Missouri

    Harry Truman.

  12. Re:Class 'C' address space for sale. by anticypher · · Score: 4, Informative

    But you don't "own" that netblock, you were allocated it from ARIN for a single use.

    Put it on eBay and ARIN will then send you a polite email about how they have now reclaimed the netblock since it obviously no is no longer being used for it's original declaration. They will then turn around and allocate it to the next demand in their queue. They have all the authority, you have none.

    If your sale goes though on eBay, for selling something that did not belong to you, you have committed fraud. I hope you have put aside some of your windfall for legal fees.

    the AC

    --
    Hemos is like...sci-fi fans;he thinks technology is cool, but he hasn't bothered to understand the science it's based on
  13. Migration to IPv6 (it's on it's way) by Midnight+Thunder · · Score: 4, Informative

    There is a lot of feet dragging going on, partly because too many business plans rely on short term spending. The irony is that some of the companies which you expect to be leading the way in IPv6 migration don't even have web sites that are IPv6 enabled. This includes IBM, Apple, Microsoft, RedHat and Cisco. I make the point because they should be picking up the torch now that research sites have already done their part, and showing that it is an achievable goal, and not some sort of pipe-dream. /. readers at the same time, should probably get to know and understand the technology, since it is not a question of whether it will happen, but when. When it happens if the IT crowd doesn't understand IPv6, then we really have issues.

    If you want to get an IPv6 web site running there are number of solutions, including using Apache 2 with IPv6 support activated and making sure you have an OS that supports an IPv6 stack - most modern OSs do.

    Migration technologies for people stuck behind IPv4 NATs include Aiccu and Teredo (Vista includes this, and for other OSs there is Miredo). If you are at home, then one of the 'consumer' routers to support IPv6 out of the box is the Airport Extreme. If others support it out of the box I am not aware of this.

    When you are ready see the dancing turtle - if you don't see it you are accessing it via IPv4.

    Other stuff you can do in the meantime is checking to see if some your favourite network based applications handle IPv6 and if they don't make some noise. Its best to make the noise now, when it doesn't matter so much, than waiting until it does. On the bonus side they can advertise the fact they are IPv6 ready.

    --
    Jumpstart the tartan drive.
  14. Re:Well duh by Tony+Hoyle · · Score: 3, Informative

    Certainly on the home side... go into the average store, and it's easy to count how many home routers are ipv6 enabled. none at all.

    Some can be adapted - my wifi router can route ipv6 but not talk it for example. No way all that hardware is going to be replaced within two years.

    OTOH we've been hearing the doomsday scenarios from the ipv6 zealots for 10 years now, and I'm not seeing it - it's still easy to get a block of IP addresses (I asked for 8 and got given 16 'just in case' for example).. we're not seeing the beginnings of a shortage yet.

  15. Re:Is this REALLY a problem? by anticypher · · Score: 5, Informative

    I'm so glad someone else is aware of this problem, NAT can't be infinite, or even large.

    I saw a Cisco presentation years ago on their experiences from rolling out NAT internally. They started with an address overload of a /24 (251 usable addresses) into a single external IP address. For an office with about 120 active machines, the NAT box (biggest, beefiest box they made at the time) completely fell over. With only light internet use, the NAT tables filled to take over all of the outgoing 65k ports in short time. That was in 1998, when most internet use was web pages, some email and simple IM. At the time, they recommended no more than a /26 (59 usable addresses) per external address.

    Move forward to 2007, and I made an updated presentation (for Cisco and non-Cisco NAT kit) that took into account all the new kinds of traffic we see, office workers who listen to internet radio, streaming video, youtube, multimedia conferences with H.323, peer-to-peer apps like Skype, other internet telephony apps, etc. Turns out that more than 15 to 20 active office users stuck behind a single overloaded external address would be the limit, even with a tight policy to prevent non-work traffic.

    It is much worse for ISPs with home users, who are not limited by workplace rules against peer-2-peer for popular TV shows or looking at pr0n pages. If you look at the typical pr0n page (it was a tough job, but I did it in the spirit of improving my understanding of the industry ;-), there will be between 200 and 300 embedded elements or links to affiliate sites and advertising partners. So every pr0n page view going through NAT takes 200 new external ports, with associated timeouts and state tables. A typical pr0n user (I'm guessing here, you the /. reader can supply your own values), can open a dozen or more pages in tabs in a relatively short period of time, leading to 10s of thousands of entries in the NAT state table. Remember, you have 65,533 maximum entries in the state table for a single external IP, or for a typical saturday night in basement-dweller-land, about 4 machines.

    Don't get me started about how many NAT states a typical 3Mbyte facebook page can open, and leave open for quite a while.

    If you think you can hide many ISP customers behind NAT, there are limits if you don't want a ton of calls to the support lines when your users can't effectively use the net. For modern home connections, that already have a NAT box with a handful of machines behind the NAT (Mom keeping 20 eBay pages open and doing Skype, Dad doing gaming, teenage son looking at pr0n and daughter with 20 different IM chats going while she P2Ps the latest TV episode and looks at 50 different bebo and facebook pages), you just can't NAT much more than that.

    That post was the voice of experience, if you want the nice real-world figures in a printed report and a keynote or powerpoint presentation to your CTO, you have to give me money.

    the AC

    --
    Hemos is like...sci-fi fans;he thinks technology is cool, but he hasn't bothered to understand the science it's based on
  16. Re:Is this REALLY a problem? by Rich0 · · Score: 4, Informative

    I must then be imagining the public web server that I run over my NAT'd DSL connection.

    You probably are if you are really behind an ISP-run NAT. We're not talking about the Linksys router that you can tell to forward port 80. We're talking about the ISP handing you a non-routable 192.168.x.x address and not forwarding anything to it. Outward-ONLY connections...

  17. Forgive me if I don't seem alarmed by merreborn · · Score: 4, Informative

    The IPv4 crunch has been 2 years away for at least 10 years.

    By the way, the idea of reallocating parts of Class-A blocks has been technically feasible for over a decade. Say hi to CIDR

  18. Re:FUD by MightyYar · · Score: 3, Informative

    Yes, but do they actually? Oh, yeah.

    Here's a completely random example: slashdt.org (obviously getting typo hits from slashdot...

    According to This web site, that domain shares an IP with over 14,000 other domains!
    --
    W..w..W - Willy Waterloo washes Warren Wiggins who is washing Waldo Woo.
  19. Re:Well duh by Tracy+Reed · · Score: 4, Informative

    China, Korea, Japan etc. use lots of ipv6. I've been there, seen it, helped set some up. There is a whole Internet out there full of asian language websites out there that we don't even know about because our english only Internet doesn't link to it. Go to a cyber cafe in Hong Kong, Beijing, Seoul, and you'll see what I mean.

  20. Re:What's wrong with this plan? by Neil · · Score: 3, Informative

    IPv4 packets would be turned into IPv6 packets in the IPv4 subset of the IPv6 address space when they left the IPv4 endpoints, and then turned back to IPv4 if the destination didn't support IPv6.

    Unfortunately the IPv4 address space isn't embedded in the IPv6 address space in the way that you suggest. Dan Bernstein pointed out many years ago that this was a mistake.

  21. Re:Is this REALLY a problem? by misleb · · Score: 3, Informative

    I saw a Cisco presentation years ago on their experiences from rolling out NAT internally. They started with an address overload of a /24 (251 usable addresses) into a single external IP address. For an office with about 120 active machines, the NAT box (biggest, beefiest box they made at the time) completely fell over. With only light internet use, the NAT tables filled to take over all of the outgoing 65k ports in short time. That was in 1998, when most internet use was web pages, some email and simple IM. At the time, they recommended no more than a /26 (59 usable addresses) per external address.


    Really? We currently NAT well over 160 machines to a single external IP address and have had 0 problems in years. Users have unrestricted internet access (and they use it).

    If 160 machines are filling up 64k of ports, something is seriously wrong with the translation algorithm. Perhaps old connections aren't being reaped properly?

    t is much worse for ISPs with home users, who are not limited by workplace rules against peer-2-peer for popular TV shows or looking at pr0n pages.


    Is it worse for ISPs? I used to work for an ISP that would NAT whole high rise condominium/apartments of home users with no problems other than pure bandwidth.

    If you look at the typical pr0n page (it was a tough job, but I did it in the spirit of improving my understanding of the industry ;-), there will be between 200 and 300 embedded elements or links to affiliate sites and advertising partners. So every pr0n page view going through NAT takes 200 new external ports, with associated timeouts and state tables.


    It is a good thing browsers limit themselves to the number of simutaneous requests, isn't it? What is it, like 6? An intelligent NAT gateway will close a translation when the client does. A pr0n page will NOT take up 200 external ports.

    Remember, you have 65,533 maximum entries in the state table for a single external IP, or for a typical saturday night in basement-dweller-land, about 4 machines.


    Bullshit.

    Don't get me started about how many NAT states a typical 3Mbyte facebook page can open, and leave open for quite a while.


    How many? I'd really like to know how braindead your router is that it doesn't know how to close translations when the TCP connection is terminated.

    If you think you can hide many ISP customers behind NAT, there are limits if you don't want a ton of calls to the support lines when your users can't effectively use the net.


    Again, bandwidth was our only limitation.

    For modern home connections, that already have a NAT box with a handful of machines behind the NAT (Mom keeping 20 eBay pages open and doing Skype, Dad doing gaming, teenage son looking at pr0n and daughter with 20 different IM chats going while she P2Ps the latest TV episode and looks at 50 different bebo and facebook pages), you just can't NAT much more than that.


    You can. You're full of shit. (Or is it FUD?)

    That post was the voice of experience,


    No, it was the voice of someone who just pulled a bunch of numbers out of his ass. 4 user limit behind a residential gateway? Come on, you can't possibly believe that.

    -matthew

    --
    "THERE IS NO JUSTICE, THERE IS ONLY ME." -Death