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Your point (and reply) about memorization was good. Yes, I'm not constantly remembering "210.40.138.43" but enough tech people need to remember some of these things - for debugging, support, etc - that IPv6 is painful. Asking someone to verify an IPv4 in a dialog setting is doable - an IPv6 is not.

I've maintained for 2 decades that simply adding another 2 slots for 0-255 would have opened up a greatly usable amount. Every current v4 - 210.40.134.34 - would also be 0.0.210.40.134.34, but we'd have another 65000 groupings of 4 billion addresses to allocate as needed, and a transition would have been far easier (smaller space, less processing, easier to think about, etc).

I use copy and paste for both IPv4 and IPv6 addresses.

I understand where you are coming from by adding a few more bytes to the address scheme but one of the things IPv6 was designed for was massive address aggregation which means really short routing tables. Your 192.192.168.168.0.0 (say) scheme does not go far enough. Also, your scheme needs to be efficient in the world of bits and bytes and I don't think it is. Your scheme would probably need to be 64 bit to start with and not 48 bit because silicon, etc doesn't work like that.

However that simple routing scheme was blown out of the water by private addressing - ie get your own ISP independent address range. When you change ISP you end up with another prefix and hence all your addresses change. All addresses. So you buy your own range (about £3000 set up and £3000 per year from memory. You also need an ISP(s) to route it and if more than one then a BGP peering arrangement.

Another wrong in the name of IPv6: 64 bit IPv6 prefixes from an ISP means you can only have one subnet. No way to put your dodgy IoT stuff on its own VLAN.

Sorry I'm not sure i understand:

> Another wrong in the name of IPv6: 64 bit IPv6 prefixes from an ISP means you can only have one subnet. No way to put your dodgy IoT stuff on its own VLAN.

Can't your router handle carving up a subnet just fine?

A lot of self-assigned IPv6 networks just tack on the device's 64-bit MAC address on to the end of some 64-bit network prefix. So if you're going with self-assignment of IPv6 addresses then you will have difficulty if your assigned prefix is already 64-bits, since you can't really use any of the 64-bit suffix bits for your own network.

The mechanism is called StateLess Address Auto-Configuration (SLAAC) [0]. It removes the need for DHCP, and the determinism is very convenient. There are of course privacy downsides for deterministic addresses that are globally routable, and that's where SLAAC privacy extensions come in [1].

[0] https://en.wikipedia.org/wiki/IPv6#Stateless_address_autocon...

[1] https://en.wikipedia.org/wiki/IPv6#SLAAC_privacy_extensions

More precisely, disabling the autonomous addressing flag in the router advertisement packet allows you to completely control the addresses which will then only be handled by DHCPv6, which allows you to slice a /64. But that means no v6 temporary addresses for anonymisation, which might be exactly what you want in a managed network/corporate scenario which requires liability tracing.

What are you using at layer 2 that has 64-bit MAC addresses?

The recommendation is to assign a /56 to end users from an ISP. That would give you plenty of subnets to work with.

/56 == 256 /64s Each /64 == 18,446,744,073,709,551,616 addresses

Sadly, plenty of ISPs use DS-Lite with a single /64 issued.

(I'm looking at you UPC/Virgin Media/Liberty Global)

Vodafone cable in germany does the same..

I have a pretty good ISP - I get a /56 but the original idea was /48 for everyone. I only have 256 subnets available. With /48 I would have say 256 x 256 subnets which would be ideal for my family. With /56 I have very little elbow room.

Each subnet (/64) is 18,446,744,073,709,551,616 addresses - which is nice.

That only helps in making the addresses seem more familiar but does not solve any of the other problems IPv6 solved. You would still need two separate protocols anyway because there is no backwards compatible way to route that.

NATs break end to end. This might be acceptable in a HTTP(s) only world though.

Of course, some people aren't only using the Internet for browsing.

The Internet of things will end up needing unique endpoints, and NAT does not play will with those either.

India has a lot of people, and quite a few of them will be IPv6 only (or behind a very degraded carrier grade NAT). If you are talking to customers/clients/vendors there, assume you need IPv6.

Memorising IP addresses isn't done in any larger scale network, you use DNS.

NATs work well at about the scale of a single household, beyond that, they keep making things worse.

> NATs break end to end. This might be acceptable in a HTTP(s) only world though.

I was always curious about this argument -- do you mean that NAT elimination will allow any two arbitrary devices to communicate with each other?

I would think that even in IPv6 world, the firewalls would still be a necessity. Most ISP would continue shipping routers with stateful firewall enabled by default (to prevent internet exploits), so any peer-to-peer software would still have to deal with UPnP/STUN/TURN. Sure, the STUN protocol will be simplified a bit because it would not need to worry about IP changing, but it would still be way more complex than just a simple connect() call.

Note that the situation maybe better in some cases -- like for India or for cell phone networks -- but there would still be enough people behind the firewall to make arbitrary incoming connections unreliable.

Related: the privacy extensions seem to be a pretty bad idea. I have no idea how would I set up a firewall to say "allow incoming traffic to my main laptop, port 22222" if it's IP address always changes. Ideas like "disable privacy extensions" and "filter by MAC" have their own significant downsides.

NAT elimination will indeed allow arbitrary devices to communicate with each other. Whether they do so will depend on the end users.

Stateful packet filters will still be necessary, but those would be end user configurable.

Keep in mind that you are thinking about a NAT you control. If your ISP is NATing you as well, you would have a very different impression.

I'm a techie too but I think:

- If you go around memorising addresses then you are doing IT wrong in general. So many things depend on DNS (not just A records) that punching in IPs by default is a bad habit. Browsers will keep on enforcing SSL/TLS more and more until the point where typing in an IP address into the URL bar will be as painful as using the web GUI for say an elderly HP switch is right now.

- In general latency is not affected by header lengths these days. In some cases, networks are prioritising IPv6 for the opposite affect. In other cases ISPs have dropped their entire IPv6 support without noticing for quite some time. sigh

- The addressing scheme in use should have nothing to do with your privacy. Yes NAT does accidentally hide you a little bit. However I can fingerprint your browser instead, for example. I'll trade easy SIP n RTP over NAT any day.

Now, for my gripes:

- Try doing multi WAN effectively over IPv6 without PI and a routing algorithm, or NAT - Try changing ISP (new addressing everywhere)

The second gripe I currently work around with RFC 4193 - Unique Local IPv6 Unicast Addresses, the first one I whine about and will probably use NPT (wholesale NAT for IPv6)

> - If you go around memorising addresses then you are doing IT wrong in general. So many things depend on DNS (not just A records) that punching in IPs by default is a bad habit. Browsers will keep on enforcing SSL/TLS more and more until the point where typing in an IP address into the URL bar will be as painful as using the web GUI for say an elderly HP switch is right now.

Most of the things I do with memorised addresses have nothing to do with the browser or HTTP. (Mind you, though, the moment a browser won't let me access a bare IP, I'm switching away from that browser.)

> - In general latency is not affected by header lengths these days. In some cases, networks are prioritising IPv6 for the opposite affect. In other cases ISPs have dropped their entire IPv6 support without noticing for quite some time. sigh

I wondered if this may be the case; I may need to rerun some tests.

> - The addressing scheme in use should have nothing to do with your privacy. Yes NAT does accidentally hide you a little bit. However I can fingerprint your browser instead, for example. I'll trade easy SIP n RTP over NAT any day.

A website I navigate to may, but how will the carrier fingerprint my browser?

All in all, it seems like we are talking about very different threat models to privacy/security. You are worried about the likes of Google and Facebook profiling you, whereas I am worried about the likes of $intellectualpropertymonopolist sending me a $20k bill for identifying me in a torrent, or experiencing a nasty surprise at $nationalborder (or at home, [1]!) for something I said on an internet forum.

(This does not seem like an abstract or overblown threat to me; I've seen 2 out of the 3 things above happen to friends and even one schoolmate more than 2 times.)

[1] https://www.theguardian.com/uk/2012/nov/12/teenager-arrested...

Most of the things I do with memorised addresses have nothing to do with the browser or HTTP. (Mind you, though, the moment a browser won't let me access a bare IP, I'm switching away from that browser.)

Me too. Wireshark, nmap and co are in regular use in my job. All browsers are playing nanny, more and more apart from the likes of Links (which I also use quite often). A lack of https is already flagged and I suspect that things will get worse in this regard. Links2 has saved my bacon many times in the past so you may enjoy it 8)

You are worried about the likes of Google and Facebook profiling you

No mate. I'm CREST accredited: I'm not worried about G and F profiling me - I know they do. However I also know that my choice of addressing scheme does not affect my privacy whatsoever. A carrier can use metadata to derive loads of facts about your usage even if you are connecting to the oher end over say https. NAT will save you from some silly firewall screw ups but not much else. A VPN can help but is no silver bullet either. If I really put my mind to it I could probably make myself near enough anonymous with enough use of proxies, VPNs and TOR but I'm not too sure about that!

I too am from the UK and have seen silly overreactions such as your [1] link. However, this is the world we have nowadays and in our case we have a horrific level of CCTV pointed at us as well as some pretty impressive levels of IP traffic mining. We also have the rather unpleasant RIP Act and a few others to belie our supposed liberal way of life in the UK. You do have to be careful what you say nowadays, within reason.

Well, my assumption was always that in a scenario such as: ISP makes me share my public-facing IP with 15 randos -> I get on a torrent for Sony Corporate Secrets [full pack] [2018].zip -> Sony's legal department connects a honeypot and harvests all IPs it sees on it and sends out subpoenae to identify everyone who is in a friendly jurisdiction, the circumstance that I'm NATted by my provider will actually do nontrivial work in reducing the probability that I am ultimately identified in a legally actionable way (especially if it were to take Sony a while to process its data). Is this not accurate?

Your ISP would usually have port mapping logs.

GDPR in theory means that we should be able to tell exactly what data ISPs have about us.

But surely you can visit a McDonald's car park, run tor-browser and download whatever that Sony thing was without being traced.

>- If you go around memorising addresses then you are doing IT wrong in general.

Because I'll surely have an TLD for my local nginx and for my home router...

You can buy a DNS domain for a few quid per year or you can use a dynamic DNS service such as freeDNS for err free.

If you go around exposing services on the internet then you should know how to do it properly. If you can get a name on it then you can put a SSL certificate on it (cheers Lets Encrypt).

If you have a SSL cert on it then you can be fairly sure you are talking to your gear and not a MitM if you take other precautions.

I absolutely do have a LE SSL cert for my home router and all my home web sites. pfSense has a ACME and dynamic DNS client for many services and HA Proxy built in. What more could you want!

With IPv4 you don't HAVE to buy a domain for your local network. You can do just fine with IP addresses. With IPv6, you probably will need to just to make it sane. That adds a whole new step, and a complex one that most people (general public) won't know how to do.

To be fair, most of the general public doesn't know what an ip address is.

I'm in the group that you're speaking of—I have a personal server set up that I can log into remotely, but the prospect of setting up a domain and TLS is very daunting. But, I don't think people like me are all that common.

Just use home.arpa from https://tools.ietf.org/html/rfc8375 with a custom DNS server or host file. Or one of the many dynamic DNS systems.

Sure, because a custom DNS server is easy to set up.

It's actually pretty easy. I was able to set one up when I was a teenager, almost 25 years ago, in the early days of the commercial Internet. It is even simpler now.

Yes, it is.

Depends on your skill set. If you're ok with *nix, then PowerDNS is pretty simple to work with:

https://github.com/PowerDNS/pdns

It's also fairly complete, used in production by some pretty big ISPs.

For a light weight approach instead, Dnsmasq is good:

http://www.thekelleys.org.uk/dnsmasq/doc.html

It's what most home routers (and lots of other stuff) embed. :)

Ok, fair enough. It’s fairly simple to set up.

It’s just a bit of a pain to maintain if the only thing you care about is connecting to server nr 192.168.0.x

I could certainly do it, but there’s 5 services in my house I’d care to connect to, and remembering 1-5 is just as easy as giving them all names. The marginal gains are very low.

Oh, I very much agree. For very small local networks in a flat address space, manually remembering stuff works ok.

Personally I tend to throw the more stable IP addresses in /etc/hosts, as that's simple too. :)

Ever heard of dnsmasq? Comes with many home routers. Puts a dns entry for each host that gets it's ip address via dhcp, plus your static mappings.

.local?

Using .local in DNS is a violation of RFC6762. You really ought not to do this.

It's also too long for something you type a lot. I use .hm.

This is easily solved with mDNS/Avahi. I had the same gripe years ago, now my hosts advertise their own records or even on behalf of others without running a NS.

> If you go around memorising addresses then you are doing IT wrong in general. So many things depend on DNS (not just A records) that punching in IPs by default is a bad habit.

If you are debugging network connectivity, then I have a tough time believing it’s possible without typing in a few network addresses.

> - If you go around memorising addresses then you are doing IT wrong in general. So many things depend on DNS (not just A records) that punching in IPs by default is a bad habit. Browsers will keep on enforcing SSL/TLS more and more until the point where typing in an IP address into the URL bar will be as painful as using the web GUI for say an elderly HP switch is right now.

This heavily reminded me of the good old Night Watch essay[1]. You can punch DNS names into the address bar on a browser, because someone out there traded normal sleep schedules for the tremendous opportunity to think about BGP trees, netmasks, and other exciting arcana.

[1] https://www.usenix.org/system/files/1311_05-08_mickens.pdf

> Why do people keep treating "you get your own unique IP address when browsing" as if it were an advantage?

The original tenet of the internet pretty much hinged on the idea that every person with a computer can host/self-publish information as well as consume other people's information in a distributed way. They will not have to depend on a centralized publishing authority.

I think v6 could have enabled this

> Why do people keep treating "you get your own unique IP address when browsing" as if it were an advantage? The way I see it, NAT and IP address reuse (especially together with some European countries' laws stipulating the address->identity mapping must be deleted within some time period) are the currently most widely rolled out privacy technology. ...

Although IPv6 doesn't have NAT, per se, it does have Network Prefix Translation (NPTv6). And some VPN services (FrootVPN and Perfect Privacy, for example) have already implemented that.

I have no real first hand knowledge of this, but I have wondered if part of the reluctance of ipv6 is the fact that many of the "powers that be" use ip addresses to identify and group traffic and other activity from multiple devices. They also use ip addresses to block scrapers (both Google and Amazon do this heavily).

With ipv6, an IP address can be completely disposable. You could scrape Google search results all day long and use a different address for each call.

Heck, you could completely proxy search results in real time and create your own search engine, secretly using Google as your backend while injecting your own ads.

Wouldn't you be bound to a specific subnet dedicated to you? Or how does it work? Can you really just propagate to the world at any time "I am now baba:fefe:..."? Don't backbone routing tables get crazy mad verbose that way?

I know next to nothing about ipv6, I'm afraid.

It would be a random address from a given subnet, yes. Basically the privacy, tracking and banning implications of this are more or less the same as they are with v4+NAT, with the v4 public IP mapping to the v6 subnet.

Note that there's still no way to map a subnet to a person, just like there's no way to map a public v4 address to a person.

Huh, are you implying that with IPv6, the ISP can place multiple unrelated people in the same subnet but not coordinate with them regarding what address from the subnet they use? How does this work from a routing perspective? What if two people pick the same address?

On the other hand, if the ISP ultimately does hand out the address in the subnet (and the end user can merely ask it for a new one), the ISP can retain a record of this, which together with the server-side data can be used to unambiguously deduce who accessed what, whereas the equivalent information in v4+NAT is insufficient without also logging everyone's connection metadata. It would therefore be more appropriate to say the privacy, tracking and banning implications are the same as dynamic IPv4 without NAT, where you can likewise request a new address from your provider at any time.

Normally what happens is: you request a prefix from the ISP (call it a /56, which is 256 subnets of /64 size each), then you pick one /64 from the prefix and use it for your network. Your computers then assign themselves randomly-selected addresses from the /64.

The prefix might be 2001:db8:1:2300::/56, the first network 2001:db8:1:2301::/64, and the machines on that network 2001:db8:1:2301:random:numbers:go:here.

The ISP knows who has which prefix, because they handed them out, but the allocation of IPs inside that prefix is handled entirely by the end-user network. The ISP isn't involved in it, so they have no idea which IP is which computer.

With NAT the LAN-side IPs are hidden from the ISP. In v6 the ISP can see the LAN part of the address, but without any way to identify which machine is using which IP that doesn't give them any extra information. All they get is the prefix and a random number. Computers typically change the random number on a regular basis too so you can't even do any long-term analysis on it.

Oh, I see where the misunderstanding is. In cases like the one addressed in Belgium, the ISP actually assigns the same outward-facing IP address to multiple unrelated customers, and NAT is performed on the ISP side. Somebody who has merely recorded the IP address that made a request therefore has no legal way of determining that it came from you or someone close to you, rather than a number of complete strangers who were assigned the same address, unless the ISP maintains a record of what connections were mapped. As far as I know, in the US this is mostly common for mobile providers. If we are just talking about a NAT in your home LAN, this won't help you for privacy/security: law enforcement and whoever else still know that the IP address is yours.

That would normally be called CGNAT. Yes, that does change things somewhat... except what's actually going to happen is that people will record the port number and the time as well as the IP, and the ISP is going to record every single connection you make in a big database, and then bill you for the privilege of doing it. Law enforcement will still be able to identify you, now your ISP has a record of everything you've done, and you're still dealing with the headaches of NAT all the time. Doesn't really seem worth it to me.

As far as I know, several court cases in Germany have confirmed[1] that the mapping of dynamically assigned IP to customer identity may only be stored for 7 days. I imagine the same upper bound, or an even tighter one, applies to the records you are talking about.

[1] https://www.e-recht24.de/news/datenschutz/10387-datenschutz-... (in German)

ISPs use port logs for the same reasons as address logs so I imagine a court would treat them the same.

Around here I'd expect something more like a 7 year minimum to be more likely...

Limiting the timeframe does improve the costs and the privacy impact, but the ISP will still need to build and run all of the logging infrastructure, and the end result is that you'll still be identifiable.

If you try to do this at scale you'll find you won't get transit anywhere. Any AS will drop routes from you when Google looks their way. If you think you can ignore them, they'll just threaten upstream. You'll be cut off in hours.

It works the same way on v4 and v6.