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UK ISPs Respond To the Dangers of Using Carrier Grade NAT Instead of IPv6
Mark.JUK writes "Several major Internet Service Providers in the United Kingdom, including BSkyB, Virgin Media, TalkTalk, AAISP and Fluidata, have warned that the adoption of Carrier Grade NAT (IPv4 address sharing) is likely to become increasingly common in the future. But the technology, which many view as a delaying tactic until IPv6 becomes more common place, is not without its problems and could cause a number of popular services to fail (e.g. XBox Live, PlayStation Network, FTP hosting etc.). The prospect of a new style of two tier internet could be just around the corner."
A few of the ISPs gave the usual marketing department answers, but three of them noted that they've been offering IPv6 for ages and CGNAT is only inevitable for folks that didn't prepare for what they knew was coming. Which, unfortunately, appears to be most of the major UK ISPs.
If, and only if, they do offer IPv6 services to their customers than I am pretty cool with this. Realistically IPv4 is done. There is no real other option for the ISPs than to move to this type of setup for backwards compatibility and push IPv6 for full compatibility.
Unlike the US, where if people get bad service, they get vocal and kick up a stink, the British have a tendency to just wear it. Expensive, shit service is par for the course here, and business and the 1% know it.
I've been following the IP6 thing here in the UK with interest. BT the major supplier seem to be uninterested in full IPV6 for all customers. I've seen statements that they are pursuing CGNAT for IPV6. If this is true it beggars belief. The only reason I can that makes any form of sense is the attempt to stop a proliferation of home based servers, suck as toasters, fridges, TV & PVRs etc.
They're probably looking to segment the market and screw as much money out of their customers as possible.
I didn't know Pink Floyd was talking about ISPs.
"Hanging on in quiet desperation is the English way. The pool is gone, v4 is over. Thought I'd more addresses to assign."
.. your country bought a shit load of IP address in the early day of teh Internet.
for the record:
Slovenia population: 2M
IP4 reserved IP: 2.5M
http://www.nirsoft.net/countryip/si.html
Love many, trust a few, do harm to none.
Even if an ISP implements IPv6 or dual stack for his residential customers, they will still face problems:
- IPv6-only customer will not be able to reach IPv4-only content (and I bet there will be lots of it for years)) without CGN (NAT64)
- not enough public IPv4 addresses for all customers mean that there has to be a form of NAT deployed centrally (CGN with NAT44) to provide them with IPv4 access (again, not all content is reachable by IPv6).
Of course public IPv4 addresses (going around CGN) will be still there, you will just need to pay more for them. Marketing departments are not going to miss such an occasion, after all they need a financial explanation to rollout of IPv6.
If you want to host a game server or FTP, you still can. Just pay a tad more for the privilege, right?
IPv6 by itself is not going to resolve everything and avoid CGN usage. Those ISPs who say "we deployed IPv6 and it fixes everything" forget about the problem underneath (trailing/legacy IPv4 content).
So you've got an ISP that uses ipv6 and you get your own address so every service on the internet is guaranteed to work (sort of). Then you've got an ISP where rumor gets around that you all share one IP and that might cause a gigantic list of problems, break a ton of services, prevent you from accessing millions of websites that IP-banned "you," etc. Guess which ones customers are going to go for. You need zero technical knowledge to tell someone that with one ISP a ton of stuff on the internet doesn't work and with the other it works just fine.
WTF!? He just one-hit killed me. That's some Carrier Grade bullshit right there.
At DeweyCheatam&Howe, we are committed to combining Carrier Grade customer service with Wall Street Grade executive profits.
Come on, dude, stop driving that Carrier Grade '60s clunker and get a real car!
She's my ex-girlfriend now, because that Carrier Grade whore was in our bedroom with some poolboy from down the block.
You can hold down the "B" button for continuous firing.
NAT64 is not the solution so many here make it out to be. The original sensible migration path was to use dual stack and get most services over to ipv6 before the v4 space ran out.
Everyone here knows the problems with less than 1:1 NAT in a pure v4 world. Slashdot'ers complain bitterly about it all the time. NAT64 brings all those problems and more.
Think about this. Suppose your v6 only mail relay needs to send mail to a v4 only relay. It looks up the MX for the domain, than looks up the name it gets in response. Oh there is only A record no AAAA. Okay no problem right?
We will just set up our DNS server to generate synthetic AAAA records when only an A rec exists and prefix the A record with the ipv6 network address spaced allocated for NAT'ing to the ipv4 space. Sounds good but now you have to give up DNSSEC or deal with even more complexity.
Oh that remote mail server wants to a reverse lookup? How does a v4 only host deal with ipv6 PTR record? it probably doesn't. In any case the source ip points back at an address being used by the NAT gateway; but that's dynamic so the DNS server is going to have aware of the NAT device and probably be capable of generating synthetic PTR records on the fly.
NAT64 is probably fine for the base case of contacting some webserver via http(s). It really falls down pretty fast when you think about other protocols, and typical SOPs on legacy systems that make all kids of assumptions about ipv4 addressing. Its not just smtp either think about all the stuff both older UNIX and Windows systems do by source subnet. Which by definition are the ones you have the NAT64 gateway in the first place. As for WWW access a traditional layer 7 proxy server for use when only an A record exists is likely a better choice.
This feet dragging that's gone will mean that largish deployments of things like NAT64 are likely to be required; and that's unfortunate; because it takes what would have been a somewhat complex transition and turned it into something that is going to be a costly train wreck with difficult and confusing brokenness all over the place.
Repeal the 17th Amendment TODAY! Also Please Read http://www.gnu.org/philosophy/right-to-read.html
the big providers in the US, and many of the rest, are IPv6 enabled in the core. but edge equipment at the subscriber is not up to the task, so NAT IPv4 is how it's done here. virtually all of the DSL modems are MD'd (manufacturer discontinued) IPv4, so it makes sense.
if this is supposed to be a new economy, how come they still want my old fashioned money?
CGN has already happened in countries that were late on the Internet bandwagon and got too few IPs.
I am currently an unfortunate subscriber going through CGN, and let me tell you, the time I spent debugging connectivity issues is mindblowing.
For those who don't understand the extent of the problem, CGN is also called NAT444:
Your internal network has an IPv4 subnet, say 10.17.0.x. Then your router is allocated an IPv4 from your ISP. You think that's your IP, but it isn't. Your ISP itself is running NAT internally, and ultimately your data is being sent through the wire to the wider Internet with yet another IP.
So you have 3 networks: IPv4 IPv4 IPv4
Practically speaking, nothing that acts as a server will work. i.e. none of the modern multiplayer networking stacks work reliably, for example. When testing your PS3 networking, it will say (correctly) that you are screwed because you have a "Type 3 NAT", which is Sony speak for NAT444.
As you wrote - each of ISPs mentioned in the article says in one way or the other that CGN is a neccessity.
Most also say they have no immediate plans to deploy CGN as sufficient IPv4 address space is available within their allocations.
Every last one of them have already or are in process of deploying IPv6.
Problem with IPv6 is that the business case is weak.
Q. Hello, I am Interested in Internet service, do you offer IPv6?
A. No, there is no business case for us to do so.
Q. Thanks for your time....click.
For me this is already reality today. Every RFP without exception we have participated in last 3 years either required or asked about IPv6.
ISPs have to spend money upgrading to IPv6 without offering anything new to get more income from subscribers.
CGN and "pay more for a public IPv4" is, sadly, one of such cases that is likely to go forward
This was never about providing anything "new" it is about getting to *continue* to provide the same level of service.
CGN costs more not only in terms of hardware it costs in customer support and administrative resources required to manage the system vs dumb packet punters.
As an ISP the less CGN you need the less you spend. The more IPv6 you deploy the less CGN you need.
This article was totally lacking in any useful facts about why CGN (Carrier Grade NAT) won't work just fine. As you can see today, lots of games and things like Skype manage just fine to talk to other devices that are also behind a NAT. One of the many ways they do it is ICE (http://tools.ietf.org/html/rfc5245). Most applications today are designed to work behind NATs, that is because most people are behind NATs. Sure, I wish I could wave a magic want and have everyone using v6 but articles like this that have no factual information on what the problem is or why don't help.
This is exactly what a lot of people fail to see. The free market is like Portland cement: stop stirring it for too long and it loses its fluidity and sets into cartels. And say what you will about the EU, they're doing a relatively good job at continuously prodding the big market players for the good of the consumer. Especially compared to the US, where a lot of providers of common services (like cell and internet) overprice and underdeliver.