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A brief history of IPv4 address space exhaustion

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Re: A brief history of IPv4 address space exhaustion

#41

Post by FullyFunctional »

kstrauser wrote: post #39
FullyFunctional wrote: post #26

I find DJB's take on this interesting: https://cr.yp.to/djbdns/ipv6mess.html EDIT: Dan has many excellent points, but I'd like to quote my favorite: The IPv6 designers made a fundamental conceptual mistake: they designed the IPv6 address space as an alternative to the IPv4 address space, rather than an extension to the IPv4 address space. Indeed, what were they thinking! It's certainly an undeniable fact that IPv6 ad…

That post is incredibly obsolete. In reality, a big chunk of the Internet is already running IPv6 in production as we speak.

That comment is incredibly uninsightful. In reality, the majority of the Internet is still not on IPv6 meaning that you still can't make do (easily) with only an IPv6 connection. Dan's point are true regardless of the adoption rate.

Re: A brief history of IPv4 address space exhaustion

#42

Post by djsumdog »

metalliqaz wrote: post #2

I now receive a block of IPv6 from Comcast. I allow the router to assign them to devices on the network, but I admit that I am somewhat worried that my local PC is no longer isolated from the Internet by a private IP.

I was at a company that made a mistake like this during their IPv6 rollout. The firewalls are different an individual, and initially they only had iptables rules on their BGR and an empty ip6tables set.

Re: A brief history of IPv4 address space exhaustion

#43

Post by FullyFunctional »

cesarb wrote: post #34
FullyFunctional wrote: post #26

I find DJB's take on this interesting: https://cr.yp.to/djbdns/ipv6mess.html EDIT: Dan has many excellent points, but I'd like to quote my favorite: The IPv6 designers made a fundamental conceptual mistake: they designed the IPv6 address space as an alternative to the IPv4 address space, rather than an extension to the IPv4 address space. Indeed, what were they thinking! It's certainly an undeniable fact that IPv6 ad…

One thing I never understood in these proposals: how would two computers, one with only an extended address and the other with only an IPv4 address, talk to each other? Or two computers with extended addresses, but with a single router in the middle of their path which doesn't understand extended addresses? All these proposals I've seen appear to assume that extended addresses start being distributed only after every…

There are two issues in migration: updating software and updating configuration. The former can be completely trivial if you are just pulling down updates from someone else. The latter requires effort on your part. If the IPv6 address space had been an extension, then you wouldn't have to do any configuration to support IPv6 clients while you maintain your existing 32-bit address, valid for both stacks.

At least that's my understanding of it.

Re: A brief history of IPv4 address space exhaustion

#44

Post by djsumdog »

I've only worked at one company that had full IPv6 support. Even on my current 1GbE fibre setup with a small startup, they still don't have IPv6 rolled out to residents yet. :(

I feel like one big hurdle is IPv6 usability. You can write down and easily remember IPv4 addresses. IPv6 netmasks can get really confusing. They make sense if you expand out every block, but in reality, IPv6 requires a lot of tooling to chop up and work with address spaces in an intuitive way.

Re: A brief history of IPv4 address space exhaustion

#45

Post by cesarb »

lisper wrote: post #38
cesarb wrote: post #34

Earlier quoted context omitted.

One thing I never understood in these proposals: how would two computers, one with only an extended address and the other with only an IPv4 address, talk to each other? Or two computers with extended addresses, but with a single router in the middle of their path which doesn't understand extended addresses? All these proposals I've seen appear to assume that extended addresses start being distributed only after every…

> One thing I never understood in these proposals: how would two computers, one with only an extended address and the other with only an IPv4 address, talk to each other? Via a NAT router that talks v4 on one side and v6 on the other.

A NAT router is not enough. Suppose the v4 side wants to initiate the communication; to which address would it send the initial packet? Remember, the "v4 side" has no concept of extended addresses at all, for it every address must be 32 bits and nothing more. And it also doesn't solve the "v4 router in the middle of the path" problem.

Re: A brief history of IPv4 address space exhaustion

#46

Post by jcranmer »

gens wrote: post #30

IANA sold the blocks. There are still a lot of unused IPv4 addresses. IANA sold the blocks. PS IPv6 sucks.

The IANA blocks were exhausted in January 2011. All of the RIRs save AFRINIC exhausted their internal allocation pools since then: APNIC in April 2011, RIPE September 2012, LACNIC June 2014, and ARIN September 2015 (although note that the definition of "exhaustion" differs from RIR to RIR--ARIN in particularly relied on a truly-bone-dry definition whereas APNIC claimed exhaustion when they had less then a full /8 in their pool).

As of right now, ARIN appears to have exactly 0 IPv4 addresses--they can't even give out a block of 256 IPv4 addresses to someone who asks for it. All they can do is put you on a waiting list until someone else agrees to give up their IPv4 address space. Some people have been waiting since July 2015.

Re: A brief history of IPv4 address space exhaustion

#47

Post by bogomipz »

dboreham wrote: post #9

Unfortunately my perception is that IPv6 deployment is stalled (due to inaction by ISPs). In my company we have recently dismantled some of our IPv6 infrastructure because it became apparent that ubiquitous v6 connectivity was not coming any time soon (e.g. we have locations served by Charter/Spectrum, and they have no IPv6 and no plan to deploy it). We've instead deployed a private IPv4 overlay network between our s…

I know that for many years the eyeball networks in the US were dragging their feet in their IPV6 rollouts but I believe this has changed dramatically. Spectrum(Time Warner) states 90% of residential[1] is now on IPV6 and Comcast was at 30% 4 years ago[2]:

[1] https://www.timewarnercable.com/en/support/internet/topics/i...

[2] http://corporate.comcast.com/comcast-voices/comcast-reaches-...

Re: A brief history of IPv4 address space exhaustion

#48

Post by oasisbob »

FullyFunctional wrote: post #26

I find DJB's take on this interesting: https://cr.yp.to/djbdns/ipv6mess.html EDIT: Dan has many excellent points, but I'd like to quote my favorite: The IPv6 designers made a fundamental conceptual mistake: they designed the IPv6 address space as an alternative to the IPv4 address space, rather than an extension to the IPv4 address space. Indeed, what were they thinking! It's certainly an undeniable fact that IPv6 ad…

I think anyone who thinks DJB's proposal was a realistic easy option needs to look at the history of the class E address space (240.0.0.0/4), and the proposals to allocate it for normal use.

Despite not changing the address length at all, the idea of doing this was abandoned because of the widespread compatibility problems across different OSes.

Sure, you could hand-wave another layer of NAT to "fix" it, just like the extended address proposals.

Hell, even using MAC addresses which begin with a number devices haven't seen before is enough to cause issues, despite following the existing standards: https://news.ycombinator.com/item?id=13090945

And all the existing NAT / firewall / middleware devices - they're supposed to handle the extensions transparently? Having seen the many ways that ASA protocol / application fixup can mangle packets - I find it very hard to believe.

Re: A brief history of IPv4 address space exhaustion

#49

Post by oasisbob »

FullyFunctional wrote: post #41
kstrauser wrote: post #39

Earlier quoted context omitted.

That post is incredibly obsolete. In reality, a big chunk of the Internet is already running IPv6 in production as we speak.

That comment is incredibly uninsightful. In reality, the majority of the Internet is still not on IPv6 meaning that you still can't make do (easily) with only an IPv6 connection. Dan's point are true regardless of the adoption rate.

Sure you can - many of us have phones in our pockets right now which are doing just that over LTE.

With an imaginary phone running with an imaginary v4 extended address, you'd still need something in the network at the carrier side to handle communications with legacy devices.

There's not much difference between that and having a v6-only device.

Re: A brief history of IPv4 address space exhaustion

#50

Post by zrm »

stouset wrote: post #40
bpodgursky wrote: post #15

Earlier quoted context omitted.

I don't think that perception is accurate. Google's IPv6 tracker shows continual progress: https://www.google.com/intl/en/ipv6/statistics.html (with the expected bumps around weekends and holidays) It's not a fast process, but I don't see any evidence it is stalled.

I don't think it really matters what percent of clients are IPv6-capable. Nobody is incentivized to actually deploy servers to IPv6 while there exist zero IPv6-only clients.

The main benefit of IPv6 is that it allows all endpoints to have a real IPv6 address, including the ones that don't have a real IPv4 address.

It serves its purpose if it allows end user devices to directly communicate with each other even if cloud servers with real IPv4 addresses continue to use IPv4 until the end of time.

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