Can you give a summary? ISPs would have to assign a /32 prefix to every connection before we'd be in the same boat as IPv4, but my ISP gives out /64 prefixes (and so uses a 4-billionth as much of the address space as IPv4 does).
Didn't have time to listen to the whole thing yet, but from what I gathered it's two things: the lower 64bits of the 128bit addresses doesn't count (due to privacy), and that carrier-grade NAT might go much further than what some people think.
If all you want to do is to watch YouTube and check out Instagram, and Google and Facebook have servers in a rack "nearby" (in the network sense) ala what Netflix does, then you don't need a globally unique IP to talk to them.
> If all you want to do is to watch YouTube and check out Instagram, and Google and Facebook have servers in a rack "nearby" (in the network sense) ala what Netflix does, then you don't need a globally unique IP to talk to them.
A "consume only" internet sounds like a second rate dystopia, doesn't it? (Where does the next YouTube/Instagram/Google/Facebook come from when the hurdle is they need to install lots of middle boxes to small, more siloed networks?) Not to mention the name "internet" itself comes from the global joining of a lot of individual networks. A re-balkanized "internet" with a lot of mostly disparate networks that don't really talk directly to one another hardly deserves the name "internet" at that point. (From that perspective CGNAT is an attempt to murder the internet from the inside.)
> the lower 64bits of the 128bit addresses doesn't count (due to privacy)
That's not how that works? For privacy a device is picking a 64-bit random number, sure, but that's still 64-bits of random numbers for a lot of devices to roll before collisions. It's not like it is just one device per lower 64-bits of address space. (Sure, maybe for "privacy" to avoid easy/obvious port scanning you superstitiously avoid "unlucky numbers" like ::1 or ::ffff:ffff:ffff:ffff, but that's still a lot more random numbers to roll than anything "the lower 64bits doesn't count" implies.)
(ETA: And of course, that assumes you are using privacy-focused SLAAC. There's still the power to micromanage a prefix with DHCPv6 and allocate every single one of those lower 64-bits if you really must.)
> For privacy a device is picking a 64-bit random number, sure, but that's still 64-bits of random numbers for a lot of devices to roll before collisions.
I don't have billions of devices in my home network, yet they eat 2^64 worth of addresses cause my ISP hands me a /64.
Which is fine. There are 330 million /64s available... per person on the planet. Your home network using one single /64 out of that isn't even a blip.
(Actually, if that's all you can get then it's not fine. Your ISP should be handing you, perhaps not by default but certainly on request, at least a /56 so you can have multiple networks.)
On a personal note, I used an ISP with CGNAT for a very short while, and it was despicable. It completely, utterly breaks any possibility of peer-to-peer stuff, in million little ways like UPnP being insufficient to make online gaming work as expected. It was just awful.
If we're going to talk about "need", then you don't even need a computer. You could walk over to the rack and watch the yougram on its management console.
But there are advantages to having a computer. Similarly, there are advantages to doing your networking right, and that means globally-unique IPs.
I listened to it some more, and he goes into this more specifically.
He says that because things has to work behind NAT these days ("or it won't get deployed"), then the effective address space of IPv4 is much larger.
For one it includes the source/destination ports, but in addition those ports can be time-multiplexed, so you get more effective bits out of that. He suggests the effective address space of IPv4 is closer to 52 bits.
On the flip side, in IPv6 the recommendation is for ISPs to hand out /48's. Add a few hosts inside there, and you got an effective address space that's roughly the same as the effective IPv4+NAT address space.
I don't believe that's correct because IPv6 could have time-multiplexed ports, too, which would vastly extend the IPv6 space if the podcaster wants to compare apples to apples.
Yeah I'm note sure I entirely agree with his arguments around the address space.
His other points seem stronger, like how IPv6 is a mess for backbone router hardware due to variable length headers, how to get IPv6 working really well requires you to control the entire network and how it might not matter much since we're moving towards a naming-oriented network. Overall interesting podcast IMHO.
