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Comment by tzs | Hacker News Reader

Comcast started rolling out IPv6 across their network a long time ago. They hit 100% support on their broadband network in 2014. They run a lot of the own stuff on IPv6, such as on-demand video on their set-top boxes. I think any home modem/router that they support that did not support IPv6 hit EOL long ago and was replaced.

There may be some class A owners who are trying to hold back IPv6 so they can make money off their class A, but Comcast isn't one of them.

Apple has long had IPv6 support in their operating systems, so I don't think they have been trying to hold it back either.

Ford, Softbank, Daimler, and Prudential? It is not immediately obvious to me if they could do anything to hold it back even if they wanted to.

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Comcast ran out of RFC1918 addressing to manage all the devices on their network (think cable modems/set top boxes/routers/everything) and had a massively segmented network setup.

They rolled out IPv6 because it flattened that network again, and instead of worrying about being in the right segment for reachability everything now gets a globally unique IP address. It massively simplified their internal management.

> Apple has long had IPv6 support in their operating systems, so I don't think they have been trying to hold it back either.

And Microsoft has supported IPv6 since Windows 2000: https://news.microsoft.com/2000/03/15/microsoft-announces-ip....

I understand that LTE networks are exclusively IPv6, ditto "5G".

My frustration with IPv6 is that my home ISP (Wave Broadband's DOCSIS service) is still IPv4 and they still have no plans to roll-out IPv6 even though Wave's WaveG service has been IPv6 for as long as I can remember. I understand the cause of this is because Wave's network is incredibly hetereogenous because Wave's business-model was to expand by buying-up smaller regional cablecos but to retain their infrastructure (and talent) compared to Comcast's approach of asset-stripping (bad for employees, but good for customers...).

I want IPv6 so I can stop having to faff around with NAT. I'd love to be able to RDP-in directly to my desktop at home without having to pay companies like TeamViewer and Splashtop.

----

Update: I found Wave's peering page's IPv6 status page and it remains unchanged since 2011 (and possibly since 2008). Wow.

Compare:

https://web.archive.org/web/20110102140910/http://as11404.ne...

Live:

http://as11404.net/ipv6.html

> I want IPv6 so I can stop having to faff around with NAT.

What makes you think your ISP will give you more than one IP even when they are no longer in short supply? If it's something that has value to you, it's something they will want to be paid for.

IPv6's has a fixed subnet size of 64-bits[1]. A router needs its own subnet, ergo everyone gets their own 64-bit address range. ISPs cannot give each customer a single IPv6 address because that would require each customer to have a single device connected directly to their router with no router in the CPE - basically like how dial-up used to work. There's no demand for a service like that.

[1] See https://www.ripe.net/about-us/press-centre/understanding-ip-... . I note that there is a lot of misinformation and badly-informed blog posts in the top search results for "ipv6 subnet size" like this one, ugh: https://www.crucial.com.au/blog/2011/04/15/ipv6-subnet-cheat... - which is wrong because IPv6 simply doesn't have 128-bit-sized subnet option (whereas you can have a 32-bit sized subnet in IPv4, which is how most residential ISPs/CPEs are configured).

RIPE just has a rule about only having ISPs hand out those /64s there is nothing to prevent someone internally to then split that /64 into smaller chunks to hand out to internal clients. Thats the would point of a subnet!

I'm not sure if that's well-supported by IPv6 though. Documents I've read do agree that it's possible to have smaller subnets in IPv6 (e.g. https://docs.netgate.com/pfsense/en/latest/network/ipv6/subn... and https://serverfault.com/questions/426183/how-does-ipv6-subne... ) but that the pain and hassle required to do-so isn't worth it.

Wait, so does that mean that every customer would have 18.45 QUINTILLION addresses to use?

God, I knew the IPv6 space was insanely large, but Jesus h, man.

2001:: is a 16 bit prefix in which every single customer could get a /48, i.e. you could allocate 65k subnets of 18.45 quint addresses on your network and give one of those to everyone with an ipv4 address and not run out, and that's still only 1/65536th of the total address space.

128 bits is a lot.

(the /64 as the physical subnet allows using hardware MAC addresses and RNG temporary/private addresses instead of needing DHCP/etc).

It is not true that an ISP cannot give each customer just a single IPv6 address. The Linux box I use as a router gets a single (i.e., /128) address from Spectrum Cable on its upstream interface, and it has to explicitly ask for a separate /64 prefix to advertise on the local interface (this is called prefix delegation, PD).

So it's certainly possible for an ISP to give a customer just one IPv6 address. I'm not sure, but I think there is no rule that prefixes obtained with PD must be /64's. They could in principle give you a /126 or /127 to limit you to just a few hosts on your LAN, and charge to give you anything better. This would break stateless autoconfiguration but it would still work with DHCPv6.

Your best workaround is still www.tunnelbroker.com, HE's free IPv6 tunnel service.

Thank you for correcting my misunderstanding of IPv6! :)

> The Linux box I use as a router gets a single (i.e., /128) address from Spectrum Cable on its upstream interface, and it has to explicitly ask for a separate /64 prefix to advertise on the local interface

Ask for a /56! Spectrum in Los Angeles hands out /56s, and I understand many other residential IPv6 ISPs do as well. You get your own 8 bits worth of subnets on top of /64 for easy SLAAC address assignment. This works "for free" not only because the IPv6 address space is large enough to do this, but more importantly because IPv6 does NOT have any fixed subnet sizes - routing is hierarchical and subnet assignment is transparent. /64 is just the size used by SLAAC address auto-configuration, another bit of IPv6 magic.

Phil,

Thank you so very much for NOS, which was my very first introduction to IP over packet and what initially got me interested in amateur radio (going on 30 years ago!) and is, in part, what led to me initially getting licensed and drawn into the world of networking at a young age.

73,

N9WWV

P.S. Welcome to HN!

I'm not sure why you're getting downvoted, but I think it's yet another confirmation that this place has gone full Reddit.

Performative cynicism + speaking hypothetically about past events = I'd downvote it twice if I could. In reality very very few ISPs are giving one IPv6 address per customer. ISPs are greedy but they're not wantonly cruel.

> "In reality very very few ISPs are giving one IPv6 address per customer"

In actual reality, global IPv6 adoption is at ~33% [0, 1], so I'd say this is, at best, a premature and naive presumption. ISPs actively engage in rent-seeking, and resource scarcity is another contributing factor. In-short, there's nothing in OPs comment that warrants the downvotes.

[0] - https://www.google.com/intl/en/ipv6/statistics.html [1] - https://www.akamai.com/uk/en/resources/our-thinking/state-of...

wmf does have a point though. When it comes to ISPs and telecom companies, I'm pretty cynical. It's a well earned cynicism though.

Do you know about Hurricane Electric's free IPv6 tunnel broker? www.tunnelbroker.com. I have used it for a very long time, and it has been very stable and reliable. The only technical requirement is that you have control of a globally routable IPv4 address where you can set up a tunnel endpoint. I.e., "carrier grade NAT" (a contradiction in terms) won't suffice.

I still use HE's tunnel even though Spectrum Cable has provided good native IPv6 service for several years. Ping times over HE are just as good as native Spectrum, probably because everybody peers at the same place in Los Angeles.

The only problem with HE is that Netflix is clamping down on VPNs, and they consider a HE tunnel to be a VPN. So my home router advertises the native Spectrum prefix with a higher priority than the HE prefix.

My own frustration with IPv6 is that virtually no public hotspots support it. My Verizon phone does, so I often use it as a hotspot even when public WiFi is available.

> Do you know about Hurricane Electric's free IPv6 tunnel broker?

I was aware of it, but I could swear that I heard news a couple of years ago that they shut it down due to decreased demand, but thank you for letting me know it's still running. I'll see if I can use it!

Unfortunately, streaming sites like Netflix block access from HE tunnels, because they could be used to skirt around region controls (like VPNs).

My ISP (RCN in Chicago) doesn't support IPv6 either. I tried HE, but ran into the above issue. Now I'm seriously considering getting an IPv6 block directly from ARIN (and paying the few hundred a year fees) to use with HE tunnels, to work around the Netflix block.

Would love to find a cheaper solution though.

SixXS is the one that shut down: https://www.sixxs.net/main/

My friend/co-worker signed up for Wave thinking that it supported IPv6, their websites and marketing is so incredibly fragmented...

We were working on some IPv6 projects that require IPv6 connectivity, and he didn't want to faff about with a tunnel or something along those lines, so he cancelled his Wave account and switched to Comcast.

Wave lost a customer due to not supporting IPv6... it's high time that ISP's started getting on-board.

What are has both Comcast and Wave available? Most cities only allow a single cableco at a time - or was this an apartment complex?

Deploying IPv6 is nice, but it doesn't impact the value of IPv4 at all.

Any internet service you want to be widely available will need to be dual-stack as long as we are alive.

If (eventually) each service needs an IPv4 address, that implies that there isn't a shortage and thus the value of addresses would be near zero.

Maybe not. Google says their traffic is now at 30% IPv6, and climbing at 5%/year.[1]

Worldwide, Google is undercounting, because they are blocked in China. Google claims that China is 0.27% IPv6, but actually China is around 55%, according to APNIC. Policy goal in China is all IPv6 by 2025.

[1] https://www.google.com/intl/en/ipv6/statistics.html

So it's taken 25 years to get to ~30% adoption. And a few years ago APNIC reported [0] that the rate was going down - I haven't found an updated report.

In 2005 the US government mandated that all their computers be v6 connected by 2008. [1] This year they updated the mandate to 80% by 2025. [2]

I learned networking in college in 1996 and I remember v6 coming up but so far I've never had to use it and chances are that I'll be able to retire still getting away with only working with v4.

[0] https://blog.apnic.net/2018/05/21/what-drives-ipv6-deploymen... [1] https://georgewbush-whitehouse.archives.gov/omb/memoranda/fy... [2] https://www.cio.gov/assets/resources/internet-protocol-versi...

Considering that World IPv6 Launch was 2012-06-06 and nothing really happened before, it makes more sense to say that it has taken 8 years to get to ~30% adoption.

I don't think you get to roll back the odometer and start counting again just because nobody adopted a technology from the start. That's not to say that adoption won't take off at some point - a lot of technologies experience exponential growth after a slow start. But the longer it takes to get started, the bigger the risk that something better will come along.

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