Comment by onionisafruit

5 days ago

Circa 1999 I was working for Cisco as a sysadmin. I got my CCNP through internal training and considered making a career of network administration, but ipv6 changed my mind. It seemed so much more difficult and unpleasant to deal with. I didn't want that to be my day to day work.

I think the same thing happens on a different scale with ISPs. They don't want to deal with it until they have to for largely the same reason.

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onionisafruit

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sgjohnson  5 days ago

> It seemed so much more difficult and unpleasant to deal with.

In my experience it’s much easier and much more pleasant do deal with. Every VLAN is a /64 exactly. Subnetting? Just increment on a nibble boundary. Every character can be split 16 ways. It’s trivial.

You don’t even need to use a subnet calculator for v6, because you can literally do that in your head.

Network of 2a06:a003:1234:5678::555a:bcd7/64? Easy - the first 4 octets.

Network of 10.254.158.58/27? Your cheapest shotgun and one shell please.

  • krupan  5 days ago

    "Hey Bob, what network is that machine on?"

    "Easy,2a06:a003:1234:5678"

    "2806:8003: and then what, I forgot the rest?"

  • tguvot  5 days ago

    remembering 10.254.158.58. Easy - the first 4 octets.

    remembering 2a06:a003:1234:5678::555a:bcd7/64. Your cheapest shotgun and one shell please.

    • sgjohnson  4 days ago

      If you have a /48 assigned, you’ll burn the prefix in your brain. Leaves 16 bits for the network address.

      e.g. you’ll get 2a06:a003:1234::/48 from the ISP - what you’ll really need to remember is the 2a06:a003:1234:xxxx::/64 part. And I use the VLAN id for the xxxx part. Trivial.

      1 reply →

UltraSane  5 days ago

At first I though so too but IPv6 is actually easier. instead of CIDR you always have 64 bits for network and 64 for host. You get a public /48 IPv6 prefix that allows for 16 bits of subnets and then the host addresses can just start at 1 if you really want. So addresses can be prefix_1_1 if you want. And the prefix is easy to memorize since it never changes.

I DO think using 64 bits for hosts was stupid but oh well.

  • muvlon  5 days ago

    That seems oddly rigid though. I need to known in advance which networks will definitely never need subnetting so I can assign them a /64.

    Why have so, so many address bits and then give us so few for subnetting? People shame ISPs endlessly for only giving out /56s instead of /48s, pointing at the RFCs and such. But we still have 64 entire bits left over there on the right! For what? SLAAC? Was DHCP being stateful really such a huge problem that it deserves sacrificing half of our address bits?

    • viraptor  5 days ago

      > That seems oddly rigid though.

      We're past that for a decade, but various services have not caught up yet https://datatracker.ietf.org/doc/html/rfc6177

               The actual intention has always been that there be no hard-
         coded boundaries within addresses, and that Classless Inter-
         Domain Routing (CIDR) continues to apply to all bits of the
         routing prefixes.