Hi all,
I've published a document trying to analyze the IPv4 exhaustion problem and
what is ahead of us, considering among others, changes in policies.
http://www.ipv6tf.org/index.php?page=news/newsroom&id=3004
I guess this could be useful in order to understand possible implications of
modifying existing policies, or setting up new ones, or even just to create
some debate about those changes.
The document was completed last April, but didn't had the time to tidy up
until a few days ago.
Regards,
Jordi
Ugh, a link to a page with a link...
Do you have an executive summary for us?
I'm working on it ... But I think it will be really difficult to capture in
a couple of pages what the document try to explain !
Regards,
Jordi
The story goes:
Richard Feynman, the late Nobel Laureate in physics, was once asked by a
Caltech faculty member to explain why spin one-half particles obey Fermi Dirac
statistics. Rising to the challenge, he said, "I'll prepare a freshman lecture
on it." But a few days later he told the faculty member, "You know, I couldn't
do it. I couldn't reduce it to the freshman level. That means we really don't
understand it."
And he was talking about quantum mechanics. Surely we understand IPv4
exhaustion and IPv6 transitioning well enough to get it down to a few pages?
Hmm I find this topic quite interesting.
First is the belief that the Internet will suddenly break on the day when the last IP block is allocated by an RIR - the fact that most of the v4 space is currently not being announced may mean we have many years before there are real widespread shortages
Second is the belief that this will prompt a migration to IPv6, as though moving to an entirely different and largely unsupported protocol stack is the logical thing to happen. Surely it is easier and far cheaper by use of existing technology for example for organisations to make efficient use of their public IPs and deploy NATs?
As technology people we are looking at v6 as the clean bright future of IP, but the real world is driven by economics and I dont see v6 as being economically viable in the near future....
I'm also yet to hear a convincing explanation of how v6 and v4 are expected to interoperate in a v4 internet that contains v6 islands...
Steve
1. IPv4 address space is a scarce resource and it will soon be exhausted.
2. It hasn't run out already due to various efficiency improvements.
3. These are themselves limited.
4. IPv6, though, will provide abundant address space.
5. But there's no incentive to change until enough others do so to
make it worthwhile.
6. Economists call this a collective action problem. Traditional
solutions include legislation, market leadership, and agreements among
small actors to achieve such leadership.
OK?
Alexander Harrowell wrote:
5. But there's no incentive to change until enough others do so to
make it worthwhile.
5a. And consumer access products (aka Linksys-style routers and router equipped DSL/cable modems) make it's implementation simple enough for the average techophobe customer to handle with instructions or over-the-phone assistance.
6. Economists call this a collective action problem. Traditional
solutions include legislation, market leadership, and agreements among
small actors to achieve such leadership.
OK?
OK.
Steve -
For the first end site that has to connect via IPv6,
it will be very bad if there is not a base of IPv6
web/email sites already in place.
While there are going to efforts to recover unused
IPv4 space, we're currently going through 10 to 12
blocks of /8 size annually, so you may get an
additional year or two, but it doesn't change the end
state.
There's no reason for end organizations to change
their existing IPv4 infrastructure, but they do need
to get their public facing servers reachable via IPv6.
Anyone who thinks that the ISP's community can
continue to grow using smaller and smaller pieces
of reclaimed IPv4 address space hasn't considered
the resulting routing table. We've build an entire
Internet based on the assumption that most new
end user sites are getting hierarchical, aggregatable
PA assignments. This assumption is soon to fail
until there's an option for connecting customers
up via new hierarchical address space.
Interoperability is achieved by having public facing
servers reachable via IPv4 and IPv6.
/John
First is the belief that the Internet will suddenly break on the day when the last IP block is allocated by an RIR - the fact that most of the v4 space is currently not being announced may mean we have many years before there are real widespread shortages
Widespread? No. Pockets of problems? Yes.
A large corporation or .edu that got n x /16s or even a /8 of v4 space in som cases and is only using a small fraction of that has no motivation based on address exhaustion to migrate to v6. ISPs and other organizations that regularly 'go back to the well' for more address space are in a different boat. They want to be ready with a plan well in advance of the day they'd go back to the well again and have have $RIR tell them there are no more blocks to assign.
Second is the belief that this will prompt a migration to IPv6, as though moving to an entirely different and largely unsupported protocol stack is the logical thing to happen. Surely it is easier and far cheaper by use of existing technology for example for organisations to make efficient use of their public IPs and deploy NATs?
Large-scale NATs introduce their own large-scale problems. Many modern OSes include v6 stacks already, but it needs to be enabled in a lot lf those cases. Where you'll run into problems are either older machines or hardware devices with built-in IP stacks. Running a dual-stack backbone can ease some of those transitional headaches.
As technology people we are looking at v6 as the clean bright future of IP, but the real world is driven by economics and I dont see v6 as being economically viable in the near future....
That will change over time. Last I heard, the US government is in the midst of a big push to v6. I wouldn't be at all surprised to see some federal grants come with riders requiring v6 connectivity in the not-too-distant future. That will get the attention of the large .edus with legacy v4 assignments and the businesses that have federal research grant funding as a significant part of their cash flow.
jms
John Curran wrote:
Interoperability is achieved by having public facing
servers reachable via IPv4 and IPv6.
The end to end principle is preserved by having hosts have unique public
ip addresses which are routed so they can be reached.
Hi John,
I wasnt specifically thinking of reclamation of space, I was noting a couple of things:
- that less than 50% of the v4 space is currently routed. scarcity will presumably cause these non-routed blocks to be:
:- used and routes
:- reclaimed and reassigned
:- sold on
- that much of the space in use within organisations could be optimised
:- mop up unused gaps in subnet
:- return IPs to the org's pool by forcing departments onto NATs
Pushing to NAT is on the face of it similar to pushing for early adoption of v6 whereby v6-v4 gateways provide a translation. However the technology for NATs is well established, widely deployed, cheap and very understandable to any IT guy.
You also refer to routing table size. The current routing table is growing quickly but people have been predicting the tables will outgrow the technology for many years but in each case new hardware gets released and on modern routers we can take significant growth (400%?).
I dont believe routing table size comes into play in this, the simple reason is that whatever we say there will always be companies willing to take routes for money and it doesnt matter who or where they are because the rest of the world just has to route it.
I dont think that hierarchical routing will ever be a reality in todays diverse internet backbone, to not be a top tier carrier with your own ASN, and a full set of routes means you are closing your doors on selling transit. There are many thousand organisations making money from that, I cant see 99% of them bowing out gracefully to leave a few 'tier1s' behind.. that would be like turning back the clock 15 years.
Steve
Steve -
If you have a plan for continued operation of the Internet
during IPv4 depletion, please write it up as an RFC. Our
present Internet routing scheme is predominantly working
based on hierarchical routing but I'm certain there are
alternatives.
/John
If you have a plan for continued operation of the Internet
during IPv4 depletion, please write it up as an RFC.
if you have a simple and usable plan for ipv6 transition, please write
it up in any readable form!
randy
6. Economists call this a collective action problem. Traditional
solutions include legislation, market leadership, and agreements among
small actors to achieve such leadership.
You left out: The "killer-app."
Compelling content *only* available via the alternative technology. The IPv-ONLY google/porn/web/tube/iphone/whatever that enough people want/desire/need/are-willing-to-pay-for to move the network to IPv6.
--chuck
Hi John,
I am not offering an elegant technical solution that would be worthy of an RFC number! 
But I am saying that the Internet of today will evolve organically and that there are a number of ways you can get by with what we have for a long time until things get really ugly.
Justin suggested that ISPs will be hit first because they are the distributors of IPs and when they cant go back for more they will be in trouble. I can turn that around tho, as an ISP if I cant get more IP space but I have customers who NEED public IPs and are willing to pay I will just 'find' some.. if I charge a small nominal monthly fee per IP or start pushing my DSL base onto NAT rather than static or dynamic public IPs I'm sure I can quickly free up a significant portion of IPs that I can capitalise on.
I still dont believe the current Internet is a hierarchy. Theres something like 25000 ASNs out there with maybe 3000 of them interconnecting in a serious way (ie peering). If that were a corporate org chart you'd be describing it as flat not hierarchical!
Steve
Interoperability is achieved by having public facing
servers reachable via IPv4 and IPv6.
that may be what it looks like from the view of an address allocator.
but if you actually have to deliver data from servers you need a path
where data from/in both protocols is supported on every link of the
chain that goes all the way to every bit of back end data in your
system. and if one link in that chain is missing, <sound of glib idea
.
randy
You don't believe the killer app will be "sorry, no more IP addresses?"
Adrian
Hi John,
I am not offering an elegant technical solution that would be worthy of an RFC number! But I am saying that the Internet of today will evolve organically and that there are a number of ways you can get by with what we have for a long time until things get really ugly.
Interesting... We likely differ on how long "a long time" is, and
definitions of what happens when things get really ugly.
Justin suggested that ISPs will be hit first because they are the distributors of IPs and when they cant go back for more they will be in trouble. I can turn that around tho, as an ISP if I cant get more IP space but I have customers who NEED public IPs and are willing to pay I will just 'find' some.. if I charge a small nominal monthly fee per IP or start pushing my DSL base onto NAT rather than static or dynamic public IPs I'm sure I can quickly free up a significant portion of IPs that I can capitalise on.
You can, and this will work for a while. When it stops working
(which is not at all predictable) you're going to need a fairly
sizable IPv6 Internet so that you can continue to connect new
customers up, and unfortunately, that means we need to start
getting folks moving ahead of time since we don't exactly know
how long your workarounds will last.
I still dont believe the current Internet is a hierarchy. Theres something like 25000 ASNs out there with maybe 3000 of them interconnecting in a serious way (ie peering). If that were a corporate org chart you'd be describing it as flat not hierarchical!
I'm guessing we've got tens of millions (if not hundreds
of millions) of organizations connected to the Internet,
and that's being done with 25000 ASN's and 400000
routes... That's absolutely the result of hierarchical
provider assigned addressing in extensive use.
/John