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Comment by 9dev | Hacker News Reader

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?

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> 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.

> 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?

> 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).

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.

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