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IPv6 Watch

ipv6.watch

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Re: IPv6 Watch

#31

Post by gorgoiler »

Scene_Cast2 wrote: post #18
fintler wrote: post #15

A basic understanding of what an IPv6 world will look like really didn't click for me until I read the IPv6 Address Planning book by Tom Coffeen. Before that, I really just saw it as IPv4 with longer addresses. Once you dig into the details, you come to the realization that it's a nearly complete reinvention of IPv4. Network planning looks quite different (especially when it comes to subnets) when you plan them with…

Could you give a brief overview of your current understanding? I'm curious as to why /60 would be too limited, and how it's different from IPv4.

[not OP, but hey…] There’s no need for DHCP with IPv6. Clients choose the last 64 bits of an address randomly. The address space is huge — zero probability of a duplicate address.

The first 64 bits therefore identify the network. If your ISP routes a /60 to you then you get to split that into 16x /64s.

That’s probably fine, but the IETF recommendation is to dish out a /56 to small sites and give them a /48 if they ask for it. ISPs usually have multiple /32s at their disposal.

It’s not about number of available addresses or networks. The joy of IPv6 is the addresses are so wide you can bring back hierarchical addressing. No internal routing chicanery is needed.

If your site has 64 buildings then a /56 lets you assign a /62 to each, with 4x VLANs in each building eg for printers, guest net, phones, lighting, admin, with even a subnet for each business function in the building.

Re: IPv6 Watch

#33

Post by amarshall »

quantico wrote: post #7

It feels ironic to post this on a site which itself does not support IPv6.

It does support IPv6, though.

    $ dig +short ipv6.watch aaaa
    2a01:4f8:1c1c:4b9f::

    $ curl -6Is https://ipv6.watch/ | head -1
    HTTP/1.1 200 OK
Unless you mean HN? Feels strange to me to make that comparison.

Re: IPv6 Watch

#34

Post by berniemadoff69 »

the 'funny' factor is totally unnecessary.. "yes" "no" or "somewhat" would have been much better and straightforward if you wanted to convey some information about the ipv6 status of these sites.

Re: IPv6 Watch

#35

Post by fulafel »

lovecg wrote: post #4

There’s probably a good reason for it, but I’ve never understood why IPv6 couldn’t be fully backwards compatible. Then there would be no need to migrate - everyone would be already on IPv6 by definition.

You can't fit the bigger address into the v4 address field, on the wire or in API/ABI. Also, conflating them would bring massive confusiin when v6 and v4 hosts can't reach the same addresses.

Re: IPv6 Watch

#36

Post by lovecg »

bejelentkezni wrote: post #12
lovecg wrote: post #4

There’s probably a good reason for it, but I’ve never understood why IPv6 couldn’t be fully backwards compatible. Then there would be no need to migrate - everyone would be already on IPv6 by definition.

If I recall correctly, ipv6 addresses beginning with 0::0:ffff are mapped 1-to-1 with ipv4 addresses.

I’m mostly still annoyed about the colon. Come on, ip:port is a pretty widely used convention people! The number of parsing bugs I had to fix with the migration…

Re: IPv6 Watch

#38

Post by adkadskhj »

fintler wrote: post #15

A basic understanding of what an IPv6 world will look like really didn't click for me until I read the IPv6 Address Planning book by Tom Coffeen. Before that, I really just saw it as IPv4 with longer addresses. Once you dig into the details, you come to the realization that it's a nearly complete reinvention of IPv4. Network planning looks quite different (especially when it comes to subnets) when you plan them with…

How useful would that book (IPv6 Address Planning) be to someone not working specifically in networking/ops? I like developing applications and i manage, of course, my home network.

I'd love a book that gives me everything i need to know about IPv6. From justifications, to things to know when working with it, implementing it, using it in my local network, etc.

I don't perhaps need or care to learn it at a super low level, but i do want a complete understanding of it for my specific use cases. Applications and home networks, i imagine. For a novice in networks, to be clear.

Thoughts?

Re: IPv6 Watch

#39

Post by t0mbstone »

obedm wrote: post #5

Can someone explain to me what does IPv6 offer that's IPv4 doesn't? Apart from way more addresses. A good article would suffice.

It simplifies aspects of address configuration, network renumbering, and router announcements when changing network connectivity providers.

It simplifies processing of packets in routers by placing the responsibility for packet fragmentation into the end points.

The IPv6 subnet size is standardized by fixing the size of the host identifier portion of an address to 64 bits.

Re: IPv6 Watch

#40

Post by duskwuff »

whoknowswhat11 wrote: post #20
duskwuff wrote: post #16

Earlier quoted context omitted.

How does an IPv4-only host send a packet to an IPv6-only host?

They could have at least let ipv6 only folks talk to ipv4 more easily. Something like 464XLAT maybe built in out the gate more? You go ipv6 until next hop is IPv4. If you are in IPv4 mapped address space translate to IPv4 there and continue.

> They could have at least let ipv6 only folks talk to ipv4 more easily.

And how do the IPv4 hosts talk back?

464XLAT is one solution, but it requires infrastructure to be in place to perform the protocol translation. The protocol alone isn't enough to allow interoperation.

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