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The world in which IPv6 was a good design

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Re: The world in which IPv6 was a good design

#81

Post by azernik »

hueving wrote: post #51

>They have to be special, because an IP node has to be able to transmit them before it has an IP address, which is of course impossible, so it just fills the IP headers with essentially nonsense Not nonsense! The global IP broadcast is specified as 255.255.255.255 and is used by other protocols. The source IP address for the initial discovery is indeed 0.0.0.0, which is not intuitive, but the rest of the DHCP exchang…

In fact, most residential ISP modems run DHCP over whatever their L2 technology is - cable or DSL.

Re: The world in which IPv6 was a good design

#82

Post by azernik »

beagle3 wrote: post #73
beagle3 wrote: post #70

I am very glad IPv6 didn't catch on. The world in which it was designed was not a world in which everyone (NSA, Google, Facebook) was trying to document and correlate every tiny thing you do, whether it is related to them or not. If IPv6 eventually becomes widespread, I hope it comes with ISPs that will let you replace your prefix, and phones/hardware that will randomize your suffix - otherwise, the internet becomes…

Would a down voter care to explain why I am so wrong in their opinion?

Because a) statements in your comment are false, b) some proposals in your comment have already been implemented, and c) the ones that haven't are bad ideas.

IPv6 has caught on (I'm commenting from an IPv6-only connection right now, on a residential US ISP).

Most clients do perform RFC4941 suffix randomization.

Replacing the prefix destroys one of the most useful features of IP addresses and in particular the larger IPv6 address space - routability (the property that getting to two addresses that share a prefix usually uses the same next-hop router).

Re: The world in which IPv6 was a good design

#83

Post by keeperofdakeys »

anilgulecha wrote: post #68

One big UX mistake of IPv6: it was not made backward compatible with IPv4. (v6)0.0.192.168.1.10 == 192.168.1.10(v4). This simple design when planning and rolling it out would have meant incrementally updating the networking stack to also support v6. Now it turns out v4 and v6 are completely different, and no one has a big enough reason to make the change until everyone else makes the change. Hard chicken-egg problem.

With the way IP Routing works, every router on the path makes a routing decision. So two people on the "new IPv4" would be unable to talk to each other if even one router on their path doesn't understand the new format. Not to mention that to be fully compatible, you'd need a way for a person with the address "0.1.192.168.1.10" to talk to an IPv4 only client on 192.168.1.10.

Then there are switches and routers that make assumptions about incoming packets, so we can't do strange bit hacks with IPv4 packets. http://seclists.org/nanog/2016/Dec/29

Switching to a new protocol is the only real choice at this point.

Re: The world in which IPv6 was a good design

#84

Post by Ded7xSEoPKYNsDd »

anilgulecha wrote: post #68

One big UX mistake of IPv6: it was not made backward compatible with IPv4. (v6)0.0.192.168.1.10 == 192.168.1.10(v4). This simple design when planning and rolling it out would have meant incrementally updating the networking stack to also support v6. Now it turns out v4 and v6 are completely different, and no one has a big enough reason to make the change until everyone else makes the change. Hard chicken-egg problem.

There is a straight-forward mapping of the IPv4 address space into IPv6 (you can do ping6 "::ffff:127.0.0.1"), and for new development that is also by far the easiest way to support both protocols: the application does everything in IPv6, and without writing a single line of code, the OS takes care of transparently using IPv4 when needed.

There is no mapping back from IPv6 to IPv4 (so IPv6 is backwards compatible, but not forwards compatible), but it can't be because the whole point is to have a larger address space.

Re: The world in which IPv6 was a good design

#85

Post by dom0 »

azernik wrote: post #81
hueving wrote: post #51

>They have to be special, because an IP node has to be able to transmit them before it has an IP address, which is of course impossible, so it just fills the IP headers with essentially nonsense Not nonsense! The global IP broadcast is specified as 255.255.255.255 and is used by other protocols. The source IP address for the initial discovery is indeed 0.0.0.0, which is not intuitive, but the rest of the DHCP exchang…

In fact, most residential ISP modems run DHCP over whatever their L2 technology is - cable or DSL.

DSL usually uses PPPoA (or PPPoE in a MPoA tunnel like below) over a subset of ATM (=DSL). PPP itself transports IP and provides configuration.

When modem and router are separate, the modem only provides an MPoA tunnel to provide Ethernet access to the DSL link, while the router connects to the AC via PPPoE over said tunnel.

Re: The world in which IPv6 was a good design

#86

Post by pmlnr »

Animats wrote: post #18

What he's really arguing for is a circuit-switched network, so that connections can be persistent over moves. He just needs a unique connection ID. One amusing possibility would be to do this at the HTTPS layer. With HTTPS Everywhere, most HTTP connections now have a unique connection ID at the crypto layer - the session key. If you could move an HTTP connection from one IP address to another on the fly, it could be…

Yeah, because we only ever use HTTPS protocol. No IMAP, no SMTP, nothing like that, ever.

Re: The world in which IPv6 was a good design

#87

Post by mSparks43 »

okket wrote: post #75
anilgulecha wrote: post #68

One big UX mistake of IPv6: it was not made backward compatible with IPv4. (v6)0.0.192.168.1.10 == 192.168.1.10(v4). This simple design when planning and rolling it out would have meant incrementally updating the networking stack to also support v6. Now it turns out v4 and v6 are completely different, and no one has a big enough reason to make the change until everyone else makes the change. Hard chicken-egg problem.

Backwards compatibility can not work. You can not answer an IPv6 packet with IPv4. There is no room in the header for the much bigger source/return address. You can try to do hacks like NAT (like you probably do in your home IPv4 network, which breaks/stops any peer-2-peer protocol). The IPv6 version is called DNS64/NAT64, and it breaks even more things, e.g. DNSSEC. Because it not only requires network address trans…

IPv4 + NAT is much more sane than IPv6 IMHO.

Seriously, it should not be the default that every single device on your network is visible to the great wide world. Therein be demons. Especially not all these internet of things devices that any script kiddy can make surrender all its secrets.

Plus, have you ever actually even tried a setup of an IPv6 local network?

You try typing 2001:0db8:85a3:0000:0000:8a2e:0370:7334 into the address bar 50 times in a week to tweek router settings and see how enamoured you are with the protocol.

Furthermore, you know whats easier to type in?

rrcc5uuudhh4oz3c.onion

Re: The world in which IPv6 was a good design

#88

Post by bahjoite »

runeks wrote: post #22
Animats wrote: post #18

What he's really arguing for is a circuit-switched network, so that connections can be persistent over moves. He just needs a unique connection ID. One amusing possibility would be to do this at the HTTPS layer. With HTTPS Everywhere, most HTTP connections now have a unique connection ID at the crypto layer - the session key. If you could move an HTTP connection from one IP address to another on the fly, it could be…

> One amusing possibility would be to do this at the HTTPS layer. With HTTPS Everywhere, most HTTP connections now have a unique connection ID at the crypto layer - the session key. As a network-ignoramus, who likes cryptography, I’ve long dreamt of a networking protocol where endpoints are defined, primarily, by a public key. All messages would be encrypted with the destination public key, and signed by the source p…

Something like GNUnet's CADET subsystem?

https://gnunet.org/cadet-subsystem

Re: The world in which IPv6 was a good design

#89

Post by Hikikomori »

dom0 wrote: post #85
azernik wrote: post #81

Earlier quoted context omitted.

In fact, most residential ISP modems run DHCP over whatever their L2 technology is - cable or DSL.

DSL usually uses PPPoA (or PPPoE in a MPoA tunnel like below) over a subset of ATM (=DSL). PPP itself transports IP and provides configuration. When modem and router are separate, the modem only provides an MPoA tunnel to provide Ethernet access to the DSL link, while the router connects to the AC via PPPoE over said tunnel.

Another common option is RFC 1483 bridging (IPoEoATM) where DHCP is typically used for address assignment.
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