Is it just me or did we actually start regressing in terms of moving things off IPv4? A couple of years ago I had a working IPv6 connection at home with a static /64 delegation. I had full IPv6 connectivity at work. Since I had IPv6 connectivity on my laptop ~90% of the time I actually moved a lot of my own private services to be IPv6 only, since that helped a lot with the usual background of port scans and other random annoyances.<p>Now I'm forced to move these things back to IPv4. My home ISP has first moved off static delegations in favor of dynamic ones via DHCPv6, and then broke IPv6 routing completely [1] and after a few weeks of me complaining still seemingly has no interest in fixing it. The place I work for now has no IPv6 connectivity and has no plans for it in the future. Many people I talk with don't believe that IPv6 is the future and I commonly hear that they have forcibly disabled it on their computers due to this or that random problem.<p>[1] <a href="https://www.tablix.org/~avian/blog/archives/2020/05/on_missing_ipv6_router_advertisements/" rel="nofollow">https://www.tablix.org/~avian/blog/archives/2020/05/on_missi...</a>
DHCPv6 is broken. Addresses are assigned not based on MAC addresses like in DHCPv4, but based on UUIDs. Whether the UUID is per host, hardware, boot or phase of the moon or just random is essentially random, making it totally useless for any kind of managed network. One might as well just go with the simpler alternative of using SLAAC. Any admin claiming DHCPv6 is somehow better for a managed network than the "anarchy" of SLAAC is deluding themselves.<p>There are patches and extensions doing MAC address based assignments, but those are only sparsely supported in network hardware and software.<p>For the configuration tasks that DHCP also is used for beyond address assignment, there are better alternatives like anycast, zeroconf and SLAAC extensions. The only thing that would make DHCP useful again in 2020 would be strong cryptographic authentication for devices, maybe tied in with 802.1x and MAC layer encryption.<p>Therefore I think android is just ahead of the curve in getting rid of DHCPv6.
> Android still has a broken IPv6 implementation in 2020. By design. They are not going to fix it. There are a couple of valid arguments from Google and Lorenzo Colitti, but they are pretty weak.<p>Any care to substantiate, why they are weak?<p>I'm going to substantiate, why their argument is strong:<p>1) With DHCPv6, the network operator can force your device to obtain only single IP address. With SLAAC, you can invent your own, any amount you want, it just has to be within the same subnet; the /64, smallest subnet, is pretty huge.<p>2) For tethering with IPv6, you need multiple IP addresses. You cannot do NAT as you do with IPv4.<p>Therefore, with IPv6, telcos could disable the tethering function of the phones / charge extras, just by suitably configuring their network. It is obvious, that the major supplier of mobile OS won't allow doing that. Hence, no DHCPv6.
I mean, there are two sets of standards. Google picked one, the author picked the other. The other 2000 words of the article seems to be a rant about how Google makes money off of ads.
It's a bit much to call something "broken" because it won't support the configuration you want, particularly when that configuration itself could reasonably be called "broken".<p>It sounds like DHCPv6 means giving up most of the benefits of IPv6. In which case better to migrate right than migrate twice.
> "Initially, Microsoft operating systems did support SLAAC but not RDNSS, Android did not want to support DHCPv6. That meant that you couldn’t support these two operating systems on the same subnet."<p>This is incorrect. You can run SLAAC (with or without RDNSS) and stateless DHCPv6 on the same subnet.<p>Even more, running DHCPv6 correctly actually <i>requires</i> sending RAs with the O or M bit set, so you're almost doing SLAAC anyway (setting M disables SLAAC, O does not.)<p>Sensible (= stateless) DHCPv6 is an addition to SLAAC/RDNSS to allow pushing additional config. It is not a replacement.
Just another in the long list of things that’s remained broken in android for many years.<p>If you’re worried about novice users getting stuck make defaults but don’t <i>break</i> things.
> You could, of course, run both SLAAC and DHCPv6 simultaneously, but why?<p>Because it’s what you supposed to do by design?<p>Here’s a good thread on the IETF IPv6 working group mailing list about it:<p><a href="https://mailarchive.ietf.org/arch/msg/ipv6/mqa0qZvlFF8lQWjdZi8UrY7wmLk/" rel="nofollow">https://mailarchive.ietf.org/arch/msg/ipv6/mqa0qZvlFF8lQWjdZ...</a>
Should we care about enterprises?<p>It looks like the setup they want will be pretty crap for home users if that got implemented by ISPs.<p>You won't be able to tether if ISPs / Mobile networks decide to use the DHCP to give you a single IP.<p>This stance of Google's benefits consumers. Howv many consumers are there of mobile phones and broadband are there in the world compared to workers in a corporate LAN?<p>I feel like the question that needs to be asked sometimes is:<p>Will this enterprise feature negatively affect normal home users.<p>Imagine your mobile phone network gave you 1 IPv6 address rather than a subnet.<p>That is bad. But Google standing firm on not implementing the ability to do so, has meant that they gotta implement prefix delegation.
Ok IPV6 is one of those ideas that was obsolete by the time it was deployed. 12 bytes? Why not 16? Why not a UUID for each node? No management; no guessing who's is who's. Heck, use a new one for every connection.