IPv6 support on Virgin media

[dgcarter]

Does anyone know whether (and if so when) Virgin plan to implement IPv6 on its network?

[Dagger2]

It's fun how everybody likes to argue "most people are fine with NATed v4, so we don't need v6", but the moment you extend that to "most people are fine with CGNATed v4, so we don't need public v4 addresses" they get super uppity about it.

We're out of v4, folks. CGNAT is gonna happen whether you like it or not, because there's simply no other way to continue to provide v4 service to people. That's what being "out" means. You might blame VM for doing it earlier than needed, but somebody has to go first. (In the UK that would be Hyperoptic, or any number of community and small scale ISPs -- VM aren't even close to being the first UK ISP to do CGNAT, although they'd be the biggest.)

If anything, we should be glad that VM are giving us v6 at all, so we can continue to host stuff. There are a lot of ISPs out there that do CGNATed v4 and no v6 whatsoever, which means you straight up can't host anything on them.

It's bad that VM are tying v6 deployment and CGNAT together unnecessarily, but unfortunately they've left v6 deployment so late that it starts to make sense to do that and just get all the network changes over and done with in a single project, rather than trying to get management approval for two separate network engineering projects.

[thelem]

Do we know how many customers are sharing an IP on the Liberty networks that already have CG-NAT? 29,000 seems an awful lot of people to share an IP. You only need to allocate the same IP to ten people to reduce your usage of IP addresses by nearly 90%.

CG-NAT is coming whether we like it or not. Individuals may be able to put it off by switching ISP, but that can't work for everyone (there aren't enough IPs).

As CG-NAT becomes more widespread the sites will have to respond to the problems you mention by stopping the practise of blocking by IP address.

[ravenstar68]

I've never been 100% happy with NAT.  I've always been acutely aware of it's shortcomings, and it's clear from reading the RFC that it was only intended to be a stop gap measure until the next IP standard came along.

In some ways NAT was too good at it's job, and we also had the magazines proclaiming how with NAT routers we no longer needed separate firewalls as the router did it all for us.  So small wonder that people who don't understand networking are happy to stay behind NAT.

Make no bones about it - we do need IPv6, and it's not about it being shiny and new, it's the fact that without it, the internet as a whole will become increasingly fractured.  The main concern for me is that the transition for end users be as smooth as possible.  For the most part they should not notice the transition period at all.

I can see I'm going to have to do some digging to see if anyone has a clue exactly what went wrong with IPv6 deployment in Ireland.  to see a drop from 60% back to 1% usage is alarming to say the least,  One wonders whether any lessons could be learned from it.

Tim

[Anonymous]

The Akamai IPv6 stats looks pretty suspect back in 2015. The APNIC graphs show the LG IPv6 roll out starting at the same point as the Akamai graph but it continues in a steady up and to the right manner:

https://stats.labs.apnic.net/ipv6/AS6830?c=IE&p=1&v=1&w=30&x=1

[shanematthews]

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@Morgaine wrote:

@shanematthews writes:

the internet will continue to function with IPv4, none of the big players will be affected for a long while to go.

But that's not actually what's happening, quite the opposite in fact.  It's the big players who are driving the change towards IPv6, while the small fry drag their feet and rationalize away their inertia with a variety of sometimes funny excuses.  The only reasonable one I've heard so far is "Our IPv6 firewall isn't ready yet", but that's not a card that can be played for too long, and it's not an excuse for not preparing one's IPv6 infrastructure internally.

It is easy to verify that it is the big players who are driving IPv6 deployment.  Google and Facebook carry an immense amount of traffic as network application endpoint providers, and their user base isn't narrowly techie or specialist but cuts across the entire world cross-section of Internet users so it's representative of both "big player" providers and their huge user bases.  LinkedIn has a more enterprise-themed audience, but is nevertheless a big player with a very large user base.  All of these companies also happen to publish useful statistics about their IPv6 usage:

• Google: "IPv6 connectivity among Google users" passed through 25% a few days ago, and this growth lies on a fast upward curve.

• Facebook: "Internet traffic over IPv6" recently reached 22.5% and is likewise steadily rising.

• LinkedIn: "In the U.S. we now pass 50% IPv6 usage on weekends across all devices", and around 40% for Germany.

That the big players are driving IPv6 adoption is also well described in the Internet Society's State of IPv6 Deployment 2018 publication, from which I've extracted a few snippets:

• Over 25% of all Internet-connected networks advertise IPv6 connectivity.

• Alexa Top Million Websites: 17% with working IPv6 (up from 13% in 2017)

• Alexa Top 1,000 Websites: 28% with working IPv6 (up from 23% in 2017)

And from the same Internet Society publication, three paragraphs which nail it:

Facebook reports that they are in the process of turning IPv4 off within their datacentres; IPv4 and IPv6 from outside comes to their load balancers, and behind them it is only IPv6. The effect has been operational improvements and innovation in their software. Other companies, including LinkedIn and Microsoft, have similarly stated an intention to turn IPv4 off within their networks.

Microsoft is taking steps to turn IPv4 off, running IPv6-only within the company. Their description of their heavily translated IPv4 network includes phrases like “potentially fragile”, “operationally challenging”, and with regard to dual stack operations, “complex”. The summary of their logic is both telling and compelling:

“Hopefully, migrating to IPv6 (dual-stack) is uncontroversial at this stage. For us, moving to IPv6-only as soon as possible solves our problems with IPv4 depletion and address oversubscription. It also moves us to a simpler world of network operations where we can concentrate on innovation and providing network services, instead of wasting energy battling with such a fundamental resource as addressing.”

It doesn't leave any doubt about where the big players stand.  They're blasting ahead with IPv6 at warp speed, and internally towards IPv6-only.

Morgaine.

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I think you misread what i said, i said they wouldn't be affected for a long time to come, yes they will push for it but sticking to IPv4 won't cause the big players any actual issues, their services will continue to work and customers will continue to to be able to access them, while the allocation of blocks may have come to a halt there are still more than enough IPv4's available to ISP's to allow them to continue to function just fine

[shanematthews]

@shanematthews writes:

the internet will continue to function with IPv4, none of the big players will be affected for a long while to go.

[shanematthews]

Facebook reports that they are in the process of turning IPv4 off within their datacentres; IPv4 and IPv6 from outside comes to their load balancers, and behind them it is only IPv6. The effect has been operational improvements and innovation in their software. Other companies, including LinkedIn and Microsoft, have similarly stated an intention to turn IPv4 off within their networks.

Microsoft is taking steps to turn IPv4 off, running IPv6-only within the company. Their description of their heavily translated IPv4 network includes phrases like “potentially fragile”, “operationally challenging”, and with regard to dual stack operations, “complex”. The summary of their logic is both telling and compelling:

“Hopefully, migrating to IPv6 (dual-stack) is uncontroversial at this stage. For us, moving to IPv6-only as soon as possible solves our problems with IPv4 depletion and address oversubscription. It also moves us to a simpler world of network operations where we can concentrate on innovation and providing network services, instead of wasting energy battling with such a fundamental resource as addressing.”

[Dagger2]

Google's stats showed no substantial bump in 2015 either; they spent the second half of 2015 growing gradually from 2.5% to 3.5%. I think that bump in Akamai's stats is a measurement artefact. I've seen similar things happen when v4 fails but v6 continues to work, meaning that v6 is a larger percentage of the remaining traffic, although not normally for 6 whole months.

but sticking to IPv4 won't cause the big players any actual issues

You're not paying enough attention to the big players (which is understandable, since they tend to be pretty private about most of their operations); they've been hitting issues due to v4 exhaustion for years and years now. So far they've been able to manage by throwing time and money at the problem, and/or by degrading the service they offer to users, but who ultimately pays for that?

[jonathanm]

As far as I remember mobile network providers are using GC-NAT (at the APN) to serve all of their customers so I imagine scaling has been long solved in one way or another.

However, I'm also guessing that some of the issues that have been mentioned also perhaps aren't so prevalent as I doubt there are a significant number of people that would choose to regularly game or provide hosting, etc. over a mobile network connection in preference to a fixed line broadband connection.

IPv6 solves the problem for mobile provider (or users) as they could then, in theory, provide a unique v6 address per connected device, compared to NAT'd v4.

[Anonymous]

Lol

 Fixed broadband providers like VM have an two orders of magnitude more data flowing through their networks. VM have almost 1Tbps of interconnect bandwidth through LINX for example.

Scaling is really non trivial at this scale.

[fyonn]

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@Dagger2 wrote:

It's fun how everybody likes to argue "most people are fine with NATed v4, so we don't need v6", but the moment you extend that to "most people are fine with CGNATed v4, so we don't need public v4 addresses" they get super uppity about it.

We're out of v4, folks. CGNAT is gonna happen whether you like it or not, because there's simply no other way to continue to provide v4 service to people. That's what being "out" means. 

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has anyone on this thread indicated that we don't need v6? I think the entire point of the thread was the very opposite 🙂

and Virgin have been telling us for the entire 7 years that I've been on this thread that they have more than enough ipv4 addresses for their customers. that was one of their justifications for not bothering with ipv6 up until recently. So to then decide to remove those addresses would rankle somewhat.

[impromptu]

The DS-Lite with public IPv4 address is an interesting one - it actually makes the problem a lot simpler.  Instead of needing a stateful CGNAT (that remembers the port and maps it to a client IP), the edge router just needs to (de)encapsulate the v4 packet in its v6 wrapper and send it on its way.  That's stateless, so can be done much more efficiently - could be done at line rate with suitable hardware. At this point the ISP network is v6 only, but customers have full v4 routing so it shouldn't break any apps.  Unlike DNS64 and friends it's completely transparent to the end user.

It doesn't solve the v4 exhaustion problem, but that could be done opportunistically (eg new customers don't get a public v4, or put lower tier customers on private v4, or some other criteria).