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Comment by throw0101a | Hacker News Reader

> The widespread deployment of NAT and VPNs has counter acted the market forces that were assumed to make IPv6 appealing.

Tell that to everyone who is behind CG-NAT and has issues with (e.g.) video games. Or all the (small(er)) ISPs that have to layout CapEx for translation boxes.

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Honestly the games issue might be out of day. Game devs have access to great services to punch through NAT at this point.

Tech finds a way…

Which has led to every game needing a central server running, forcing centralization where p2p used to work great. Also how Skype was able to scale on a budget, something now blocked, forcing you to raise money for more ideas than before. Running a matrix(?) node should be as simple as clicking install and it's just there, next time you're with your friends, nfc tap or whatever and your servers talk to each other directly forever going forward. But nope, there always is a gatekeeper now and they need money and that poisons everything.

I don’t think VOIP was a major factor in game centralization. The big one was selling cosmetics (easily unlock able server-side in community servers), and to some extent being able to police voice chat more. Major game publishers didn’t want to be in the news about the game with the most slurs or child grooming or what not.

Central servers are useful for more than just NAT hole-punching. They’re also great as a centralized database of records and statistics as well as a host for anti-cheating services and community standards enforcement.

Peer to Peer games with no central authority would be so rife with cheating that you’d only ever want to play with friends, not strangers. That sucks!

> Peer to Peer games with no central authority would be so rife with cheating that you’d only ever want to play with friends, not strangers. That sucks!

Back in the the day RtCW had a server anyone could run and you could give out the address:

* https://en.wikipedia.org/wiki/Return_to_Castle_Wolfenstein

There was a server that a ISP / cable company in the southern US ran that I participate in and it was a great community with many regulars.

P2P can be awesome with the right peers.

If you can run your own server then that's still a central server. That still lets a community of people work with a central authority. It's just a different authority from the game's publisher.

In that sense, Mastodon is a centralized service because it's on someone's computer. That's not really what people mean by central. They mean we're increasingly reliant on game companies for networking infrastructure.

Is that all IPV4s fault? I don't think so. But it complicates things

I think you're muddling things up more than they need to be. A peer-to-peer game is one in which players connect directly to each other but neither is the host and there is no dedicated server. Game state is maintained separately on each player's computer and kept in sync by the netcode. Since there is no single source of truth for the game-state, so players are free to cheat by modifying the game's code to lie on their behalf. There is also the side issue of bugs in the game code causing the game-states to become irreparably desynchronized.

All of these issues are solved by having a central server for both players to connect to. Whether that server is owned by the game's publisher or by an open-source community is irrelevant from a technology standpoint. However, the prevalence of IPv4 networks and stateful NAT firewalls is relevant because it privileges those central servers over true peer-to-peer connections.

I don't disagree with you, I just read your comment as deriding people who think hosting their own game servers is meaningful, because it's similar to a company server. Sounds like you didn't mean it that way.

Most people can't run their own server, because they aren't on a public IP!

Cool. You decided you don't care about that, but what if I do?

Don't put words into my mouth! I never said I didn't care about peer to peer networking and peer to peer gaming. I said it sucks if your only option to avoid cheating is to play with friends.

If you only care about gaming with friends, then peer to peer is an excellent way to do that (assuming the game doesn't have any synchronization issues, which some peer to peer games do).

So we acknowledge v4 and CG-NAT are a problem but don't want to use the already available solution because game developers took it upon themselves to DEFEAT NAT :)

That just reminded me of a peer protocol I worked on a long time ago that used other hosts to try to figure out which hosts were getting translated. Kind of like a reverse TOR. If that was detected, the better peering hosts would send them each other's local and public addresses so they could start sending UDP packets to each other, because the NAT devices wouldn't expect the TCP handshake first and so while the first few rounds didn't make it through, it caused the NAT device(s) to create the table entries for itself.

Was it Hamachi that was the old IPX-over-IP tunneling? I'm fairly sure it used similar tricks. IPX-over-IP is also done on DOSBOX, which incidentally made it possible to play Master of Orion 2 with friends in other continents.

I can spin up a NAT puncher today without having to depend on anybody. Can't say the same for IPv6.

> That just reminded me of a peer protocol I worked on a long time ago that used other hosts to try to figure out which hosts were getting translated. Kind of like a reverse TOR. If that was detected, the better peering hosts would send them each other's local and public addresses so they could start sending UDP packets to each other,

Sounds similar to STUN, really.

If that's the VOIP thing, yes, lots of people came to similar methods. That particular thing was for exchanging state, not VOIP or tunneling, so as long as participant groups overlapped it didn't really need a fixed server to be the middle which was handy for our purposes, although long network interruptions could make reconvergence take a while.

Does make me chuckle that so many people had to be working around NAT for so long and then people are like "NAT is way better than the thing that makes us not have to deal with the problem at all." Just had a bit of NAT PTSD remembering an unrelated, but livid argument between some network teams about how a tool defeating their NAT policies was malware. They had overlapping 10.x.y.z blocks, because of course they did :)

Nat hole punching works... most of the time. There are many edge cases and weird/broken networks which you just can't work around in standard ways. You get to see all kinds of broken setups if you work at VoIP providers. That's why everyone will use a central proxy server as the last resource - you'll mostly notice it only because of a higher ping.

Isn't CGnat due to IPv6 use on the mobiles? You could quit and say that's an IPv6 problem that didn't get solved in the IPv6 engineering

Why would CGNAT be deployed as a response to IPv6 on mobile? I don't understand the logic there. CGNAT is deployed due to a shortage of publicly routable IPv4 addresses. IPv6 was introduced due to having much larger publicly routable space.

Because the internet as a whole is ipv4. The mobiles are IPv6. The ipv4 internet does not care about any server running on any mobile device.

Thus, CG Nat was invented so that IPv6 could talk to IPv4 and get the information from it.

No, CGNAT (Carrier-Grade NAT - https://en.wikipedia.org/wiki/Carrier-grade_NAT) is an IPv4 only thing. https://www.rfc-editor.org/rfc/rfc6598 specifies they should use 100.64.0.0/10 for it, to avoid conflicting with the pre-existing private-use ranges. IPv6 removes the need for using CGNAT, as each home router is allocated a public IP (rather than a CGNAT IP) on its public link.

Oh so cgnat exists for ipv4 addresses to talk to IPv6 servers? Is that what you are telling me?

Because all of the www is in IPv6, and cgnat actually excuses for ipv4 cable users to use the bedrock internet servers and services?

Bullshit. Cgnat is a hack for ipv6 to talk to the ipv4 universe.

Because if there were magically enough iov4 addresses for mobiles, would cgnat exist? No, it wouldn't.

No, CGNAT has absolutely nothing to do with IPv6. CGNAT is nothing more than ISPs not providing a public IP to the gateway on your LAN (i.e. your router). To avoid conflicts with existing ranges, a new ranges for that purpose was allocated. There are different technologies to enable IPv4<->IPv6, none of which care about the existence of CGNAT.

No, NAT64 was invented so v6-only hosts could access v4-only resources. CGNAT was invented so v4 hosts can have a v4 address without having to purchase limited public address space.

IPv6 is used on mobile networks since there aren't enough IPv4 addresses. Some of these mobile networks are so big there aren't even enough private IPv4 addresses for their CG-NAT private side to fit, leaving the only clean solution being NAT64/DNS64.

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