I work for a (smallish) ISP so let me tell you why you will simply not get any IPv6 service without DHCPv6 on our network.

It has nothing at all to do with being IPv4 old-timers. That is just you not understanding the complexity of the world out there. Our network was build from the start with the idea that IPv6 is the future.

We use DHCPv6 to provide every user with his own /48 prefix. Yes you said that DHCPv6 is a great solution for prefixes. But we also use it to deliver a /128 to go with that prefix. We need this to have a stable and predictable address that we can use as next hob for your shiny new prefix.

We had this very same debate on the NANOG mailing list. Some people there asked why does your routers not sniff the DHCPv6 packet and add the route dynamically? Two reasons. One, that is not in any standard, so our vendor did not implement it. Two, it does not work if you have router redundancy (how would the backup router know the route?).

There are more reasons an ISP would not want to use SLAAC. It exposes 2**64 addresses to the ISP network access routers. This can harm the network in many different ways and you simply do not want your ND caches to be full of that crap. You want to use as few slots in the shared ND cache per user. Therefore you are going to disable SLAAC on the customer edge and use some other mechanism. One guy suggested not using GUA on the customer links and only use link local addressing here. We choose to use /128 DHCPv6 assigned addresses. In either case, GUA-SLAAC is a fail in the provider network.

SLAAC is great inside the household of our customers. But we leave that decision to the customer and his choice of CPE-router.

The problem with Android is that it should really be able to act like a CPE for tethering purposes. Therefore is should be able to accept our CPE configuration. Android should also be able to ask for a prefix to be sub-delegated from the house CPE and it should accept that this might come with extra addresses that will be used for routing or for other purposes.

Where to start?

1) IPv4 vs IPv6 has nothing to do with ASN. If you do have an ASN you will be using the same ASN for both protocols. With 32 bit ASN now in wide use, there is nothing limiting you from applying for one. Get your own /48 prefix with it.

2) IPv6 has NAT.

3) Multihoming is perfectly possible using IPv6. There is no rule telling you not to do it exactly like you always did with IPv4.

4) There is no rule that say you can not split a /64. You can split it down to /128 if you want. The only thing that breaks is SLAAC but you can still use DHCPv6 or static/manual configuration.

5) All major ISPs are giving out /56 or more address space, so you have no need to split a /64.

6) All major operating systems use privacy extension enabled by default, so you MAC will not be exposed when you surf the net. Your device will be no more tracked than with IPv4-NAT since it changes address all the time.

All IPv6 gives you are options. There are now more ways to do the above things. But in no way did you lose the ability to keep doing things like yesterday.

::ffff:a.b.c.d is what is used inside programs that want to use just one socket type (IPv6) to handle both protocols. I believe your OS might very well refuse to configure that on an interface.

I admit to abuse fd00::/8 but not any more than what the IPv4 think brings you anyway. Using the very first network of fd00::/8 will bring you the pain of colliding with everyone else that did exactly the same, but you will not likely collide with someone who cared enough to generate a global unique ULA prefix. This is 100% equal to having the majority of home networks on the same /24 network (192.168.1.x). You lose the advantage that IPv6 was supposed to get you, but some people here seems to be dead set to lose all that if they can, just because they don't like hex.

In another livetime I made a fd00:: prefix generator: http://bitace.com/ipv6calc/

Oh I see. You did not get the fact that when I type ping6 2001:778:0:ffff:64:0:8.8.8.8 on my IPv6 only computer, then I am in fact pinging 8.8.8.8 which happens to be a real IPv4 only server out there. You said why didn't they embed the old number plan in the new one - and they did. Multiple times actually.

If I have a NAT64 device on my local network, then my IPv6 only machine can in fact communicate with IPv4 only devices. The packets will go through the NAT64 device, because there simply is no other way - and that is a technical problem, not administrative.

We have seen a zillion proposals for alternative "IPv7" plans including yours. None have explained how that scheme would allow an old IPv4 client to speak directly with an IPv7 client. Because there is no such scheme, it is impossible. IPv4 was not made to be extendable so it is not.

You point to phone numbers. The phone numbers were made from the start to be extendable. It was never type 8 digits exactly. Never type less and never type any more - but that is exactly how IPv4 is. It is a fixed binary structure and there is no add an extra digit possible.

But as far as the administrative problem goes, somebody did think it would be smart if humans could type IPv4 style addresses for old stuff. So you can. I can ping 8.8.8.8 without first converting that into hex.

You are not making sense here. Of course the boxes on the same link need to share a subnet - just as they do with IPv4. So instead of 192.168.1.x/24 you would configure fd00::x/120.

Your router would be fd00::1. Your PC would be fd00::2. The printer fd00::3, the TV fd00::4 and so on. And yes that would work perfectly well. Today. You can even use DHCPv6 to make this work exactly like you are used to with DHCPv4.

The only difference here is that you need to remember "fd00::" instead of "192.168.1.".

But since you wanted it to look more like IPv4, we could point out that you can also name your network fd00::192.168.1.x. Why you would want to I don't know - but you can.

If your router is doing NAT64 it could export the legacy IPv4 network as fd00::a.b.c.d. That would make you feel home. It would not be a wrapper - you would be able to type ping6 fd00::8.8.8.8 from your computer, which happens to have the IP fd00::192.168.1.2.

All of that is possible today, although the usual CPE device does not ship with NAT64 and would not provide that configuration by default (because it is lame). But if you were to configure your own Linux router, you could make such a setup right now. There is no limitation in the IPv6 protocol stopping you from doing that. If it was smart, I am sure Linksys, Asus et al would do so.

You can. Or almost - it would need to be fd00::101.102.103.104/128 because ::101.102.103.104 (the version with 96 zero bits in front) was deprecated some time ago.

But yes, typing "ip addr add fd00::101.102.103.104/128 dev eth0" on a Linux box will work.

You would need a nat device to translate that of course, but that is no different from having a computer with a 10.1.2.3 style address.

Nothing at all is stopping you from using fd00::192.168.1.0/120 instead of 192.168.1.0/24 on your internal network. Your router can then do the NAT translation needed for both IPv4 and IPv6 destinations.

Nobody would do that of course. There is no point in trying to force IPv4 think over the IPv6 network. By default your IPv6 network is plug and play and you need not worry about it at all.

They already did that:

baldur@ballerup1:~$ ping6 ::101.102.103.104
PING ::101.102.103.104(::101.102.103.104) 56 data bytes
^C
--- ::101.102.103.104 ping statistics ---
5 packets transmitted, 0 received, 100% packet loss, time 4030ms

You can embed IPv4 address in IPv6 addresses using IPv4 syntax.

You can use it to interact with the old IPv4 network like so:

baldur@ballerup1:~$ ping6 2001:778:0:ffff:64:0:8.8.8.8
PING 2001:778:0:ffff:64:0:8.8.8.8(2001:778:0:ffff:64:0:808:808) 56 data bytes
64 bytes from 2001:778:0:ffff:64:0:808:808: icmp_seq=1 ttl=41 time=73.2 ms
64 bytes from 2001:778:0:ffff:64:0:808:808: icmp_seq=2 ttl=41 time=73.0 ms
^C
--- 2001:778:0:ffff:64:0:8.8.8.8 ping statistics ---
2 packets transmitted, 2 received, 0% packet loss, time 1001ms
rtt min/avg/max/mdev = 73.030/73.159/73.288/0.129 ms

That was a succesfull ping of 8.8.8.8 using an IPv6 only tool. The stuff I had to put in front of the address was the prefix of the nat64 gateway. Usually the user would not bother doing that manually. For example to ping slashdot I would first do:

baldur@ballerup1:~$ host slashdot.org 2001:778::37
Using domain server:
Name: 2001:778::37
Address: 2001:778::37#53
Aliases:

slashdot.org has address 216.34.181.45
slashdot.org has IPv6 address 2001:778:0:ffff:64:0:d822:b52d
slashdot.org mail is handled by 10 mx.sourceforge.net.

And ping 2001:778:0:ffff:64:0:d822:b52d which happens to the same as 2001:778:0:ffff:64:0:216.34.181.45.

Many ISPs will assign you a /48 prefix meaning you only need to remember 48 bits. The remaining bits is something you decide. You can decide it should all be zero. And all zero can be shortened to the string "::".

So your IPv6 address could be 2001:db8:beaf::

This happens to 15 characters. The typical IPv4 address is also 15 characters.

This is really easy: You will change the day someone tells you his end of the tunnel is only available on IPv6 and your grant depends on making this tunnel...

The fact that people forget is that the dual stack people have access to two internets. Single stack IPv4 people only have access to half of it. Some day you are going to want to peer with someone on the other net...

You got a /24. Good for you. There are only about 3 billion usable IPv4 addresses to be shared between 7 billion people on earth, and you got 256 of them. Yet you do not see a problem.

Maybe one day you will get a grant, that requires you to communicate with one of the people that got left out because of that attitude of yours. We can hope you will lose out on that grant, because you deserve it.

NAT puts state into the network where it does not belong. Everyone here seems to be focused on their own little home network. But have you thought about how easy it is to DoS a shared device, that tries to keep track of connections from dosens of users?

As any here should know, we are running out of IPv4 adresses. This means internet providers will deploy carrier NAT simply because there is no other choice. You will be sharing an IPv4 address with your neighbor. This is not the NAT you know today. It is a future where the kid next door provoked someone on an online game and got his IP address attacked by a denial of service attack. And you are just collateral damage because you happen to be sharing the IP address.

The ISPs are motivated to deploy IPv6 because this saves money. The carrier NAT devices are expensive and scale poorly. If you can move 50% of your traffic to IPv6 then you can also save 50% on the carrier NAT devices. Deploying IPv6 is practically free as most network equipment can do it already.

Carrier NAT devices are also a single point of failure in the carrier network. We do not like that.

There are solutions that tries to solve some of this, such as Address plus Port (RFC 6346). But this is not the NAT you know either. There will be no port forwarding from user specified ports, because you were assigned ports in some range and the port you want is in some other users range. Also all of this is much more complicated than simply deploying IPv6.

In short, in the future you will have crappy IPv4 and perfect IPv6. Why would you want to keep using the crappy IPv4?

Many here are assuming the world stands still. That there is no "we just ran out of IPv4". That we can just keep using IPv4 with no changes what so ever. But newsflash: this is not so, IPv4 is dying. Maybe it is better to do something about it now, than to wait until you really feel the pain?

The engine can throttle between 50% and 100%. It is true that even 50% of just one of the nine engines is enough to shoot the rocket back towards space. Which is why it can not hover.

But hover is not relevant. Hitting zero velocity at height zero is.

Let the rocket drop freely while continuously calculating needed thrust to hit the target velocity zero at zero height. Keep dropping until your algorithm says you need 75% thrust. At this moment you relight your engine at 75%.

Now you can do a control loop with feedback to vary the throttle between 50% and 100% with the perfect descent hitting 75%. This should be plenty to do the job.

In addition you have at least two other mechanism to help a successful landing. One is the braking by aerodynamic mechanisms that can be varied. Those might be more precise than engine throttling. Another is the landing legs. They will be designed to absorb hitting the ground at a small non zero velocity.

There is no lose or win - is this the kindergarten?

I replied to one claim and one claim only: that the PC to server ratio is in excess of a million to one. That claim is so absurd that anyone not laughing their ass off is an idiot that has trouble with big numbers.

You want me to prove there are 7 billion people on earth?! You are more stupid than a kid in first grade.

This does not stand to even 5 ms of thinking. I am living in a country with 5 million people. You are claiming we have 5 servers or something like that.

Or if you are an american: How many cities do you have with more than 5 million people? How many cities with more than 5 servers? ...

Or ... there are about 7 billion people on the earth. Lets assume that each have a PC (many don't). You are claiming there are only 7000 servers on earth.

Here we have a very effective law that put a complete stop to the non-compete bullshit: any company that wants a non-compete contract will have to pay half salary for the entire period where said non-compete contract is valid.

So if you stop working somewhere, they have to keep paying you half salary, if they really think that non-compete contract is necessary. They almost never do.