The question above for the most part, been reading up on it. Also want to it for learning purposes.
That’s already happened, which is why some ISPs use CGNAT. CGNAT is “carrier-grade NAT” which means the internet provider does NAT on their network.
Only having CGNAT with no IPv6 is a pain since you can’t do any port forwarding. It’s double-NAT which slows things down a bit (you use NAT on your network, then your ISP uses NAT on their network).
Some cloud providers also have IPv6-only servers for cheaper. IPv4 address are still available but the price to acquire them is significantly higher than it used to be.
Ah, I never encountered that. I see. Is it mostly in remote areas?
I’m all for IPv6, it’s just that there’s always something extra you have to do to set it up.
It’s really common in cellular connections as well as smaller regional ISPs. I work for a rural fiber co-op with about 50,000 members/customers and we do CGNAT for all our members by default because we only have about 36,000 IPs allocated to us. We also have full ipv6 support as well with every customer getting a /56.
To get a big enough block for all our enterprise/business/residential customers to do 1:1 NAT for ipv4 would probably require an entire /16 which costs somewhere in the neighborhood of 2 million dollars last I checked. And even then we would eventually run out because we are constantly expanding to cover rural areas that have been ignored for decades by the big ISPs. Right now if a member needs a static or routable we just charge 10$ a month, and we have enough in reserve for all our members to operating like this likely until the entire internet abandons ipv4.
Why do some ISPs charge a monthly fee and others a one off fee? I paid one off with my ISP several years ago for my static IPv4.
Honestly I don’t have a good answer for that. The ones who charge a one time fee are honestly being pretty generous (depending on the price you paid) considering there are yearly dues to ARIN/RIPE/APNIC/etc for IP allocations depending on their aggregate block size as well as the fact that IPs are generally very valuable right now, and go up in value depending on the block size.
If they have a legacy registration they also don’t have to pay those dues, though the downside is they don’t get the newer features like RPKI without signing a LRSA/RSA (and therefor paying those dues) and getting their routes certified. Usually doesn’t cause an issue as not many peers drop unvalidated BGP prefixes on IPv4.
That being said, if your ISP has been in the game for decades, they probably have owned their blocks for decades and got them for pennies on the dollar when ARIN and other registries were handing out IP addresses like candy. I know the last /24 my company had to buy cost us somewhere in the neighborhood of $14,000 when it was all said and done, and that was just for 256 IPs.
Eventually IPv4 addresses will become so prohibitively expensive, that is what will eventually push mass IPv6 adoption on the ASN side of things.
Thank you that was really informative. I paid <$50 for my IP address in 2015. My ISP has been around since 1990 so I suppose they may have been one of the lucky companies. Not sure if they do RPKI, first I’m learning of it. Maybe they’re cross subsidizing from other areas of the business. Their monthly fibre fee isn’t the most competitive but the service is reliable and haven’t had anything to complain about.
They are a little behind in speeds though. They only offer 900mbps asymmetrical max, while you can get 2, 4 and 8gbit in my area from other providers. I don’t need that kind of speed so I’m happy for now.
$50 one time is a great price. We charge our members $10 a month if they request a static. We’re also a not for profit coop, so all that money gets either dumped back into network infrastructure and expansion plans, or capital credits for our members.
Living in the APNIC region, we are kinda notorious for being the first region to run out of IPv4 addresses.
The top 3 mobile ISPs in my country here have been doing CGNAT since at least 2014. Cable ISPs are limiting public IPv4 according to plans since at least 2017, i.e. if the download speed of your plan is below 200Mbps , you get CGNATed.
We are severely out of IPv4 addresses.
You’ve very likely already encountered it if you have a device with a SIM card! Most any mobile provider routes via a CGNAT - it’s exceedingly rare for phones to have public IPs.
Not sure which country you’re in, but CGNAT is pretty common in some European countries. ARIN had a larger stockpile of IPv4 addresses than APNIC and RIPE, so CGNAT is less common in the USA and Canada. The US is also generally further ahead in terms of IPv6 rollout compared to other countries. One of the largest ISPs, Comcast, has been IPv6-enabled for over 10 years.
