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Why IPv6 is so complicated

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Re: Why IPv6 is so complicated

#451

Post by tardedmeme »

bborud wrote: post #448
tardedmeme wrote: post #406

Earlier quoted context omitted.

What do you think should be done instead? If ipv4 but with longer addresses (which is called ipv6) is not to your satisfaction, what would be? You want to completely overhaul the internet like in ipv8 and you think ipv8 doesn't have the exact same problems and thousands more just because it's never been deployed and nobody's encountered them yet?

You appear to not understand my argument. IPv6 is over 30 years old. The world has not embraced it. It isn’t going to. It is time to call it and try to figure out something that will work. You do understand that one need not have a better idea to make that observation? The observation is self-evident and can exist in the world regardless of what we think about IPv6 or the feasibility of figuring out something people…

So now please get to step 2 of the argument: why do you think a world that did not embrace IPv6 (a false premise by the way, as 50% of internet traffic is IPv6) would embrace IPvBBORUD?

Re: Why IPv6 is so complicated

#452

Post by tardedmeme »

zadikian wrote: post #432
boredatoms wrote: post #419

Earlier quoted context omitted.

Everyone forgets you can NAT ipv6 just like you would v4

You can, but the recommendation is no NAT with v6. Most routers don't even support it.

That's also the ipv4 recommendation, which nobody follows because it doesn't work because there are too few addresses.

Re: Why IPv6 is so complicated

#453

Post by tardedmeme »

zadikian wrote: post #387
johncolanduoni wrote: post #370

Earlier quoted context omitted.

This already exists in two forms, and has for basically the entire history of production dual stack deployments. The first are IPv4 mapped addresses (of the form ::ffff:x.x.x.x) which instruct the local machine’s network stack to use a local IPv4 address to communicate to the server. This still requires each machine to have a routable IPv4 address (though not necessarily a public one - it can be used with a NAT44 rou…

I want something:x.x.x.x to get routed to me over v6 if I had x.x.x.x in v4, as the default and recommended way of contacting an ipv6 host, without needing additional config or middleboxes. Neither NAT64 or NAT46 do this really, and they're presented as alternatives rather than the native way. The closest was 6to4. rfc6343 goes into why that got deprecated. You'd either have "router 6to4" which required additional se…

How would this work if your upstream router doesn't support v6? All other networks send packets towards you, but your ISP ignores them because they are invalid packets. Then what?

Re: Why IPv6 is so complicated

#454

Post by tardedmeme »

zadikian wrote: post #444
hackthemack wrote: post #416

Earlier quoted context omitted.

Opening a dual stack ipv4 and ipv6 does allow the service to accept both ipv4 and ipv6 connections. But I do not think that is what zadikian is getting at? It does not address the network level identity and reachability. There is no default, globally routable mapping where owning a ipv4 automatically gives you an equivalent identity in ipv6 that others can reach without translation infrastructure. The transition mech…

Yeah we're talking about the same thing. So my v4 is 70.94.201.31. My ISP didn't also give me 2002:70.94.201.31 or whatever.

They're allowed to do that if they want to. Most find there's no practical reason to ensure the addresses are related. It wouldn't help them support v6 faster.

Re: Why IPv6 is so complicated

#455

Post by zadikian »

tardedmeme wrote: post #450
zadikian wrote: post #440

Earlier quoted context omitted.

Indeed doing it this way would keep the fragmentation, or at least delay fixing it. That's what these articles always overlook, the goal of ipv6 wasn't to just add more bits, it was also to defrag the routes. I think instead of 1.1.1.1::, you could do 4:1.1.1.1::, wait for v4 to be gone, then start building new topologies in the other /8s. Not sure how hard that is, but it seems easier than what they're trying to do…

Would it help at all? You can't just send IPv6 packets down the equivalent IPv4 path because that bext-hop router probably xoesn't understand IPv6 packets. In fact there could be no IPv6 path at all between you and the destination, so knowing where they are still wouldn't help you forward packets. If it understood them, it would have given you an IPv6 route anyway. Updating BGP to support IPv6 routes wasn't an actual…

There are lots of services I can't send v6 to, not because some router in the middle only understands v4 but because the service operator decided not to deal with v6.

Re: Why IPv6 is so complicated

#456

Post by zadikian »

tardedmeme wrote: post #453
zadikian wrote: post #387

Earlier quoted context omitted.

I want something:x.x.x.x to get routed to me over v6 if I had x.x.x.x in v4, as the default and recommended way of contacting an ipv6 host, without needing additional config or middleboxes. Neither NAT64 or NAT46 do this really, and they're presented as alternatives rather than the native way. The closest was 6to4. rfc6343 goes into why that got deprecated. You'd either have "router 6to4" which required additional se…

How would this work if your upstream router doesn't support v6? All other networks send packets towards you, but your ISP ignores them because they are invalid packets. Then what?

It requires the router to support v6. If you want, could do an approach kinda like "happy eyeballs" where you try both.

Re: Why IPv6 is so complicated

#457

Post by johncolanduoni »

hackthemack wrote: post #416
johncolanduoni wrote: post #395

Earlier quoted context omitted.

You can do this quite easily on all the major OSes by opening a single dual-stack socket. On most Linux distributions that is the default, and then mapped addresses will work fine if the machine has a v4 address or a 464XLAT configuration. This has been the case for about 20 years.

Opening a dual stack ipv4 and ipv6 does allow the service to accept both ipv4 and ipv6 connections. But I do not think that is what zadikian is getting at? It does not address the network level identity and reachability. There is no default, globally routable mapping where owning a ipv4 automatically gives you an equivalent identity in ipv6 that others can reach without translation infrastructure. The transition mech…

I’m not clear on who is supposed to do the translating that isn’t doing it today, or why the mapped IPv4 addresses don’t qualify. Virtually all ISPs either give you an IPv4 address or do the translation for you, and the software you write doesn’t have to care exactly how it’s set up for the most part (there’s some subtlety about stuff like MTUs, but if you’re just doing unencapsulated TCP it usually doesn’t matter). It can just use whatever comes back from DNS (including using the official mapped addresses if only an IPv4 record exists) and expect the network stack to figure it out.

None of this stuff works perfectly, but it’s powering almost every mobile internet connection in the world so I don’t understand what is missing.

Re: Why IPv6 is so complicated

#458

Post by zadikian »

tardedmeme wrote: post #454
zadikian wrote: post #444

Earlier quoted context omitted.

Yeah we're talking about the same thing. So my v4 is 70.94.201.31. My ISP didn't also give me 2002:70.94.201.31 or whatever.

They're allowed to do that if they want to. Most find there's no practical reason to ensure the addresses are related. It wouldn't help them support v6 faster.

Do they own such an address, as in, a packet sent by someone on another ISP to that address will actually reach my ISP's router over v6? Not talking about translations that use v4. If they do, I've never seen them actually give it to me.

Re: Why IPv6 is so complicated

#459

Post by [deleted] »

hackthemack wrote: post #416
johncolanduoni wrote: post #395

Earlier quoted context omitted.

You can do this quite easily on all the major OSes by opening a single dual-stack socket. On most Linux distributions that is the default, and then mapped addresses will work fine if the machine has a v4 address or a 464XLAT configuration. This has been the case for about 20 years.

Opening a dual stack ipv4 and ipv6 does allow the service to accept both ipv4 and ipv6 connections. But I do not think that is what zadikian is getting at? It does not address the network level identity and reachability. There is no default, globally routable mapping where owning a ipv4 automatically gives you an equivalent identity in ipv6 that others can reach without translation infrastructure. The transition mech…

[deleted]

Re: Why IPv6 is so complicated

#460

Post by yencabulator »

torginus wrote: post #409
torginus wrote: post #367

My personal opinion of having worked with all layers of networking for my job without developing a comprehensive understanding, is this: We as consumers see and use the highest level, which is often https or friends, and due to the layered nature of the OSI stack, as often happens in software, if a layer is lacking in something, it gets fixed 1 or 2 layers up. If then said thing is then implemented on the layer its s…

I wish people actually put some thought into responding as opposed to just hitting the downvote button

You are being downvoted because nothing you said seems to have anything to do with IPv6. It seems you think as long as it's not your problem, it's solved?
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