473
CGNAT version 2 (sh.itjust.works)
submitted 1 week ago by [email protected] to c/[email protected]
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[-] [email protected] 143 points 1 week ago

Would you rather

  • Convert to IPv6?
  • Pay 10,000,000 per year?

The choice is yours!

[-] [email protected] 62 points 1 week ago

that's 5 cents per customer per year

[-] [email protected] 37 points 1 week ago* (last edited 1 week ago)

My reading comprehension is weak. I thought each customer should pay them $ 10M a year.

[-] [email protected] 30 points 1 week ago

Still better than switching

[-] [email protected] 5 points 1 week ago

Nice. A reason to increase the subscription with 5$ more.

[-] [email protected] 132 points 1 week ago

Every day I regret becoming a network engineer more and more

You have a clusterfuck of a clusterfuck because corpocunts make more money from keeping everyone on shit old stacks

The network engineer to communist/anarchist pipeline is real

[-] [email protected] 25 points 1 week ago

My goal is to be a network engineer...hmmmm

[-] [email protected] 19 points 1 week ago

Sounds like your goal is to be an anarchist, welcome.

[-] [email protected] 127 points 1 week ago* (last edited 1 week ago)

I would love a horror game set in a massive building with nothing but networking equipment. With the goal being to fix and patch old parts of the system finding more and more awful things that have happened to the previous employees.

[-] [email protected] 73 points 1 week ago
[-] [email protected] 38 points 1 week ago

Wow, there really is a game for everything.

[-] [email protected] 24 points 1 week ago

Well damn. I might just be sold based on the trailer alone.

[-] [email protected] 13 points 1 week ago

Nooooooo, that's gonna be a time sink.

[-] [email protected] 25 points 1 week ago

Not exactly what you’re looking for but this came across my radar recently https://store.steampowered.com/app/2939600/Tower_Networking_Inc/

[-] [email protected] 1 points 3 days ago

I now have several hours in this game. If you enjoy setting up networks and working with the equipment, this is a great simulation for it still being a super early version. And if you’re wanting to test the waters, a great way to test if it might be your thing.

Side note: Not for the OCD-inclined.

[-] [email protected] 9 points 1 week ago

I knew of Tunnet, but this looks cool. I wonder if it’s at all helpful for getting to grips with some networking intuition, I always feel behind when it comes to anything networking related.

[-] [email protected] 8 points 1 week ago

Good news, they have these, and you even get paid to do it!

Not nearly enough mind you.

[-] [email protected] 7 points 1 week ago

And the horror is the employees that turned into monsters that just want to get their computer fixed and chase you. And to placate the monsters you have to fix their problem. Each employee has a different problem. But if you mess up you just anger more employees.

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[-] [email protected] 105 points 1 week ago

oh and if any single one of those 200M customers gets caught pirating a single mp3, all 200M will go to jail forever

[-] [email protected] 46 points 1 week ago

A random one will. For each time somebody gets caught.

Or, at least this seems to be how NAT works today.

[-] [email protected] 55 points 1 week ago

Every day we move further away from God.

[-] [email protected] 50 points 1 week ago

I don't know who pulled that cabling, but they need to be hung with it.

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[-] [email protected] 42 points 1 week ago

Is that what spaghettification looks like?

[-] [email protected] 14 points 1 week ago

As far as I know, yeah, there could easily be a black hole hiding there somewhere.

[-] [email protected] 8 points 1 week ago

My report script is spaghettification

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[-] [email protected] 33 points 1 week ago

Funny how many here took this to be real, judging from the reactions. To me it's an obvious joke.

Question to you guys: How do you suppose 200 million customers will share the less than 65'536 ports that are available on that one address?

[-] [email protected] 21 points 1 week ago
[-] [email protected] 18 points 1 week ago

As @[email protected] says, you can use the same public port for many different destination address, vendors may call it something like "port overloading".

More importantly, you can install a large pool of public address on your CGNAT. For instance if you install a /20 pool, work with a 100 users / public address multiplexing, you can have 400,000 users on that CGNAT. 100 users / address is a comfortable ratio that will not affect most users. 1000 users / address would be pushing it, but I'm sure some ISP will try it.

If you search for "CGNAT datasheet" for products you can deploy today, the first couple of results:

[-] [email protected] 10 points 1 week ago

As @[email protected] says, you can use the same public port for many different destination address, vendors may call it something like “port overloading”.

I just responded to him on that point, while you were typing to me. I didn't know this existed, thanks for pointing it out!

More importantly, you can install a large pool of public address on your CGNAT. For instance if you install a /20 pool, work with a 100 users / public address multiplexing, you can have 400,000 users on that CGNAT. 100 users / address is a comfortable ratio that will not affect most users. 1000 users / address would be pushing it, but I’m sure some ISP will try it.

Sure, yeah, I have seen a few threads on NANOG about the NAT address ratios people are using. I also think I remember someone saying he was forced to use 1000 and it kind of worked as long as he pulled the heaviest users out of the pool. But if I recall correctly he was also saying he made IPv6 available in parallel to reduce the CGNAT load.

But the point that made this post ridiculous and an obvious joke is that it said "one address" :-)

[-] [email protected] 5 points 1 week ago

Well the "one address" bit sure :) but given the scale supported by CGNAT systems today, I don't think being able to support an entire country behind a single cluster is that far off. At which point the difficulty becomes "is the 100.64.0.0/10 block big enough"? Or maybe they're using DS-lite for the hauling from private network to the NAT.

[-] [email protected] 17 points 1 week ago

Easily doubled by assigning the TCP and UDP ports to different users!

[-] [email protected] 9 points 1 week ago

A TCP session is a unique combination of client IP, client port, server IP, and server port.

So you can use the same IP and port as long as the destination is a different IP or port.

This means that in principle you could use the same IP and port to connect to every IP address on the Internet using 65536 concurrent sessions. 😆

This wouldn't help going to popular destinations, since they have a lot of people going to the same IP address and port, but for many (most?) of them you probably have some sort of CDN servers in your data centers anyway.

[-] [email protected] 4 points 1 week ago

A TCP session is a unique combination of client IP, client port, server IP, and server port. So you can use the same IP and port as long as the destination is a different IP or port.

Fair point! I wasn't aware of any NAT working that way, but they could exist, I agree. It does blow up the session table a bit, but we are taking about a hell of a large theoretical system here anyway, so it's not impossible.

This wouldn’t help going to popular destinations, since they have a lot of people going to the same IP address and port, but for many (most?) of them you probably have some sort of CDN servers in your data centers anyway.

Actually we have recently seen a few content providers not upgrading their cache servers and instead preferring to fall back to our PNIs (which to be fair are plenty fast and have good enough latencies). On the other hand others made new ones available recently. Seems there isn't a universal best strategy the industry is converging on at the moment.

[-] [email protected] 8 points 1 week ago

By creating new protocols that then become new quasi-standards that every system has to integrate because "everybody else does it too"?

(and yeah this one is a joke - ridiculing something that really exists by exaggerating it)

[-] [email protected] 23 points 1 week ago

I know this is humor, but for the record this wouldn't work. Each simultaneous TCP connection needs a unique four-tuple (source address, source port, destination address, destination port). If a lot the people behind the NAT try to connect to the same place (destination address and port) at the same time (something popular like Google, YouTube or Netflix), and their source address is the same, the source port needs to be different for each connection. So after at most 65535 connections within a short time the NAT would run out of ports and no one behind the same NAT would be able to open new connections to the same place until the NAT mapping expiries.

So you could have at most tens of thousands of people behind the same NAT, maybe even fewer to make it reliable.

[-] [email protected] 11 points 1 week ago

Don't forget the tech giants are all IPv6 enabled. Google Netflix Apple xhamster Facebook Microsoft are all reachable over v6.

[-] [email protected] 10 points 1 week ago

I think one of these tech giants sounds wrong? It's Meta not Facebook

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[-] [email protected] 8 points 1 week ago* (last edited 1 week ago)

OK, bad examples. On the other hand e.g. X, GitHub, Pornhub, PSN, Steam or Discord do not support IPv6.

[-] [email protected] 1 points 6 days ago

Really discord. Didint discord start existing when ipv6 was becoming more and more normalised unlike the rest of those examples.

[-] [email protected] 5 points 1 week ago

Guess I should start using xhamster over PH for tech puritism reasons

[-] [email protected] 17 points 1 week ago

i just want fiber at my address

[-] [email protected] 15 points 1 week ago

Literal spaghetti

[-] [email protected] 6 points 1 week ago

Shit is that my computer's rear end? I haven't looked in there for years! There could be intelligent rats back there pretending to be AI.

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[-] [email protected] 4 points 1 week ago

Is the news real? :o

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this post was submitted on 03 Aug 2025
473 points (99.8% liked)

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