> especially with SLAAC

Oh no, last time I asked on HN I got 24 to 48 easy steps involving a lot more acronyms than this (please don't repeat them).

IPv6 is easy to use only if you let your one router manage everything and you give up control of your home network.

Edit: again, please don't help. There have been HNers trying to help before, but my home network is non trivial and all the "easy" autoconfiguration actually gets in the way.

There are no more acronyms. SLAAC means automatic client configuration. That's the only one you need.

> give up control of your home network.

What does that even mean? What do you gain by deciding your Apple TV should be at 192.168.0.3? With IPv6, you can just `ping appletv` and it works fine. What more "control" do you need?

> you can just `ping appletv` and it works fine.

How many service does it take to make this work?

mDNS is quite fragile.

I haven’t seen a bog-standard router yet that didn’t just do it out of the box.

I mean generally I want fixed IPs on my local network for robustness.

With IPv6 I actually want it more and it becomes possible since we can just use the MAC address as an IP address.

I have IPv6 service at my ISP right now but I'm hesitant to turn it on on my local network because it does make my firewalling concerns much more critical.

> since we can just use the MAC address as an IP address

With IPv4 you need to remember ... one number per machine. The one at the end, since it's usually a /24 and everything has the same prefix.

I'm sure it's trivial to remember mac addresses from different vendors with no connection to each other too :)

> Isn't it really stable hostnames that you want?

Hostnames are another layer. Your apple tv example may advertise itself on its own. My toys don't all do that.

That’s kind of my point, though. There is no reason at all to remember IP addresses.

I don't care to remember them, but I do want them to be consistent so there's no dependency in DNS.

My home network isn't the Internet and isn't large: DNS is a much more complicated system to keep running then just fixed IP addresses in that circumstance.

Above a certain scale, that flips but not at the home level.

At the home level, you have a home router that can do mDNS out of the box. All devices are reachable by their hostname.

A router which can be switched off sometimes, or break and delay replacement.

I don't want all my IoT devices going down because they can't resolve hostnames - that's why I set fixed IP addresses for them. It means how they communicate with each other and my network is well-defined, and works provided they have Layer 2 (easy to keep up - it works provided any 1 AP is online, whereas my internet or the router providing it can vanish).

> I mean generally I want fixed IPs on my local network for robustness.

What do you mean by robustness? Isn't it really stable hostnames that you want? I don't understand how fixed IPs increase resilience (to what?).

> I'm hesitant to turn it on on my local network because it does make my firewalling concerns much more critical.

Block everything coming in from outside the network. Allow established connections. That's all there is to it.

You're assuming there is only one internet connection in my home network, for example. The "easy" trick where your ISP gives you routable addresses does not work when there's more than one exit.

Still want to help? :)

And really... everyone is pushing for SSL everywhere - among other things so that the ISP doesn't MITM your traffic.

Why would you allow the ISP to know what machines are inside your home network then?

This doesn’t change anything about the NAT or firewall story, and having two different connections is complex with IPv4 just as well. Aside from being a fairly exotic setup for personal use anyway.

What would your ISP do with the information that there are 73 unique addresses in your network at this point in time? Especially given that devices may mint any number of them for different reasons, so you can’t even really assume that corresponds to the number of physical devices in your network?

> Aside from being a fairly exotic setup for personal use anyway.

So I should cancel one of my pipes because the "commitee" overcomplicated things in the name of autoconfiguration?

> What would your ISP do with the information that there are 73 unique addresses in your network at this point in time?

Sell it of course. Good info for targeting marketing/political propaganda per household.

> I haven’t seen a bog-standard router yet that didn’t just do it out of the box.

Which one, the one from ISP A or the one from ISP B? :)

> So I should cancel one of my pipes because the "commitee" overcomplicated things in the name of autoconfiguration?

That is absolutely not what I said. It’s a more complex setup than a single connection with either protocol, and can be solved with both.

> Which one, the one from ISP A or the one from ISP B? :)

Realistically it is going to return an A record with both addresses, maybe also the link-local one, any works locally. That is a non-issue.

What firewalling? You don’t have an ipv4 firewall?

> I mean generally I want fixed IPs on my local network for robustness.

Same here, which is why I use DHCPv6. It's pretty easy to set up, nearly everything supports it, and it's super reliable.

The only catch is that Android refuses to support DHCPv6 for some reason, which is kinda annoying since it means that you need to keep SLAAC enabled if you have any Android devices on your network. Which means that your DHCPv6-supporting devices will end up with two addresses, but there aren't any real downsides to that.

> I mean generally I want fixed IPs on my local network for robustness.

With IPv6 you can assign fixed unique local addresses in addition to dynamic public addresses from your ISP.

Honestly, it sounds more like your network is fragile rather than robust. A robust network would be able to handle the IPs changing, rather than needing them permanently set to some specific value.

the internet, in very large volume, disagrees. Am I not allowed to document the widely held common sentiment?

You are allowed to state your opinion, as am I. My issue with your opinion is that is grounded in false belief and a lack of knowledge, and rehashing it here reproduces those opinions in others.

So, like ipv4, but you lose the protection and privacy afforded by the NAT?

What protection? What privacy? Smoke and mirrors, mostly.

NAT is a firewall with extra steps. IPv6 reduces complexity. Privacy (illusion of it, anyway, just like in ipv4 NAT) is handled by private addresses.

…and if you really want to, NAT for ipv6 just works.

It's the illusion of a firewall too.

NAT changes the apparent destination address of a connection, it doesn't filter them. If a connection arrives with the destination address already set to one of your machines, NAT won't prevent it.

NAT is not a security device. A firewall, which will be part of any sane router's NAT implementation, is a security device. NAT is not a firewall, but is often part of one.

Any sane router also uses a firewall for IPv6. A correctly configured router will deny inbound traffic for both v4 and v6. You are not less secure on IPv6.

Misconfigured firewall is a gaping hole. Misconfigured NAT is not letting data from outside into your local network.

So firewall is actually worse than NAT.

Even a correctly-configured NAT will let connections in from outside, and a lot of people don't understand this.

Personally I'd count "your security thing doesn't actually do the thing it's supposed to do" as being pretty bad on the security scale. At least people understand firewalls.

> Even a correctly-configured NAT will let connections in from outside, and a lot of people don't understand this.

Yes, that's called port forwarding and it is normal thing. You actually want that.

It will let them in without a port forward in place. The port forward just rewrites the IP on an incoming connection, nothing more.

If you can reuse opened connection, but that will work with firewall too.

You don't need any tricks like that. Regular new connections will work.

No it won't because that's not how NAT is working.

It will, and if you test it then it does.

NAT doesn't apply to inbound connections if you don't have a matching port forward rule, so it kind of doesn't matter how NAT works here. This is pure routing, not NAT.

IPv4 requires a DHCP server. It requires assigning a range of addresses that's usually fairly small, and requires manual configuration as soon as you need more than 254 devices on a network. The range must never conflict with any VPN you use. And there's more. Compare to IPv6: Nothing. All of these just go away.

And concerning the NAT: That's just another word for firewall, which you still have in your router, which still needs to forward packages, and still can decide to block some of them.

The dhcp server is in the router, just like you need a router for slaac.

>IPv4 requires a DHCP server.

Windows[0]: Static IP configuration is as simple as typing an IP address into the pretty dialog box. No DHCP required.

Linux[1]: # ip addr <ip4 address> <subnet mask> <device> will set a static IP address

>It requires assigning a range of addresses that's usually fairly small, and requires manual configuration as soon as you need more than 254 devices on a network.

Is 65,536 (172.16.0.0/16) or 16 million addresses (10.0.0.0/8) "fairly small"? Are DHCP servers unable to parse networks that "big"?

>Compare to IPv6: Nothing. All of these just go away.

They most certainly do. But they're not "problems" with RFC1918 addressing and aren't "problems" at all with IPv4.

There are many issues with IPv4 and the sooner it dies, the better. But the ones you mention aren't issues at all.

If you're going to dunk on IPv4, then dunk on it for the actual reasons it needs to go, not made up "problems."