I Spent a Week Without Ipv4 (2023)

No. Your ISP or tunnel broker gives you a network prefix. Then you configure SLAAC to use that prefix and hand out addresses within it. Job done.

For example, the prefix might look like 2001:470:e904::/48. Your computers can use any addresses you want as long as they start with that prefix. Since you don’t want to manually hand out addresses to every computer, you configure a router to hand out addresses via SLAAC. Your computers will use SLAAC to discover the prefix from the router, then fill in the bottom 64 bits of the address with a random number. They then ask the local network if anyone is using that full address. If not then they are done and have a working address. If somehow someone is using that address then they try again. Servers that want a fixed address will just use their network card’s MAC address (or anything similar, if you want) instead of a random number. The protocol is the same either way.

Notice that this actually gives you some bits of your own to play with, if you want. The full address is 128 bits long. The first 48 were used by the prefix and the bottom 64 by the individual devices, leaving 16 bits in the middle. You could tell your router that the prefix for SLAAC is 2001:470:e904:42::/64, for example, and then use the other subnets for other purposes. Maybe 2001:470:e904:beef::/64 is a special subnet just for your meat freezer and associated monitoring equipment. I don't know, you get to make these things up for yourself. Maybe you manage a corporate network that has a separate VLAN for phones than for normal PCs, and a third VLAN for the guest WiFi. You can give them each a different prefix by embedding the VLAN id into the prefix you advertise via SLAAC.

There’s also DHCPv6 if you want even more control over which addresses are handed out, or you want to subdivide your network even more finely. Or if ISPs ever start handing out smaller prefixes.

> If your ISP gives you a static IPv6. Unfortunately in Germany none of the ISP for private users does (last I checked).

Sure, that’s true. But they probably don’t hand out static addresses for IPv4 either. Not without paying extra, that’s for sure. Either way if you want some static identifier for your computer(s) then the solution is the same: DNS.

Of course if you _are_ running a corporate network with a bunch of VLANS like that then you should actually get your own prefix from your RIR rather than from your ISP. Then you purchase IP transit services from your ISP rather than consumer internet access. You can then advertise your prefix(es) via BGP. Again, this is exactly what you would do for IPv4. Same software, same configuration, just longer addresses. The main advantage of this extra work is that you can keep your addresses static even if you move to an entirely different ISP. You can also use the same addresses over multiple connections to multiple ISPs for better redundancy.

I did give the answer: SLAAC.

> If your ISP gives you a static IPv6. Unfortunately in Germany none of the ISP for private users does (last I checked).

Weird, here in the UK all the ones I've had have given me a static /56. Still, the same answer for that (DDNS) exist as for dynamic IPv4 addresses, you still get the advantage of not having to deal with NAT.

Use MAC as the key for firewall and monitoring. Then you don't have multiple rules per device.

Works great for me.

But more generally, I think times have changed enough for per device billing not being a viable approach anymore.

IPv4 also has a similar, though rarely documented or utilized, shortcut system. Try `ping 1.1` for example. It expands to 1.0.0.1.

That becomes 2001:0c2d:4308::/48 instead

After that you just need to remember the subnet number and the host number. If you remember 12.45.67.8 maps to 192.168.13.7 you might have

2001:0c2d:4308:13::7

So subnet “13” and host “7”

It’s not much different to remebering 12.45.67.8>192.168.13.7

IPv4 was not designed as such, but as an academic exercise. It was an experiment. An experiment that "escape the lab". This is per Vint Cerf:

* https://www.pcmag.com/news/north-america-exhausts-ipv4-addre...

And if you think there wasn't politics in iPv4 you're dead wrong:

* https://spectrum.ieee.org/vint-cerf-mistakes

> IPv6 was designed by political process.

Only if by "political process" you mean a bunch of people got together (physically and virtually) and debated the options and thought what they thought was best.

The criteria for choosing IPng were documented:

* https://datatracker.ietf.org/doc/html/rfc1726

There were a number of proposals, and three finalists, with SIPP being chosen:

* https://datatracker.ietf.org/doc/html/rfc1752

> I firmly believe that if they had adopted any other strategy where addresses could be meaningfully understood and worked with by the least skilled network operators, we would have had "IPv6" adoption 10 years ago.

The primary reason for IPng was >32 bits of address space. The only way to make them shorter is to have fewer bits, which completely defeats the purpose of the endeavour.

And what's wrong with a newer version of a thing solving all the problems people had with it...?

There are more people than IPv4 addresses, so the pigeonhole principle says you can't give every person an IPv4 address, never mind when you add servers as well. Expanding the address space by 6% does absolute nothing to solve anything and I'm confused about why you think it would.

"Modern" tooling in the consumer space is pretty dire for IPv6 support too. The best you can reasonably get is an IPv6 on the WAN side and then just IPv4 for everything local. At least from the popular routers I've experienced lately.

Privacy extensions are worthless because there are just sooooo many ways to fingerprint and track you. If you are not at least using a VPN and a jailed privacy mode browser at a bare minimum, you are toast.

V6 privacy extensions are like the GDPR cookie nonsense: ineffective countermeasures with annoying side effects.

SLAAC sucks too. They should have left assignment up to admins or higher level protocols like with V4. It’s better that way.

* https://en.wikipedia.org/wiki/IPv4_shared_address_space

They're probably using CG-NAT, though IP changes that often is a bit aggressive.

Your website will load faster on cellphones if it supports IPv6. This is because the packets take more direct routes (because they don't go to the central CGNAT server) and because less processing is applied to them. Almost all mobile networks are now IPv6-only, with IPv4 traffic tunneled and CGNATted. Apparently T-Mobile is the rare exception.

I am suggesting the ER7212PC is not a home network device, and thus having the two functions glommed together is an anti-feature in its design.

Expecting that a router not-route IPv6 by default is to misunderstand its purpose.

Except the ER7212PC, nor anything else under the Omada (sub-)brand, is not a consumer / household device. The tagline of Omada is "Networks Empower Business":

* https://www.omadanetworks.com

>> And no, I'm not being pedantic

> You very much are.

Expecting a router to not-route IPv6 is the unreasonable thought.

Then buy a device that does default NATing and other consumer-y if you want that. Don't complain that a generic routing system routes IP—whether IPv4 or IPv6—by default.

If you want a firewall buy a firewall. If you want an all-in-one firewall/gateway/AP/whatever, buy it.

In this particular case the "problem" is not in the device but in purchasing the wrong tool for the job at hand. If you want to haul lumber buy a cargo van or pickup truck, not a VW Golf.

The ER7212PC, nor anything else in the Omada line, is not for residential consumers which is what RFC 6092—"Recommended Simple Security Capabilities in Customer Premises Equipment (CPE) for Providing Residential IPv6 Internet Service"—refers to.

And RFC 7084 has two instances of the word "firewall", one (§3.1) in reference to IPv4 NAT:

    A typical IPv4 NAT deployment by default blocks all incoming
    connections.  Opening of ports is typically allowed using a Universal
    Plug and Play Internet Gateway Device (UPnP IGD) [UPnP-IGD] or some
    other firewall control protocol.

    S-3:  If the IPv6 CE router firewall is configured to filter incoming
          tunneled data, the firewall SHOULD provide the capability to
          filter decapsulated packets from a tunnel.

Also... the ability for people to deterministically reach out to a specific device on your network is the exact same ability you use to deterministically reach out to specific devices on their networks, just viewed from the opposite side. If the Internet wasn't a place where people could decide to run services on their networks and connect to services that other people ran on their networks, what would the point even be?

IPv6 supports customer-controlled prefix rotation. You can select how often it happens by configuring your router to periodically change its DUID. Of course, your ISP can ignore this signal and always assign the same prefix anyway, but you can hardly blame that on IPv6.

You can share that IP address by putting multiple hosts on the same local network. NAT was invented because of lacking enough addresses.