Now currently I’m not in the workforce, but in the past from my work experience, apprenticeship and temp roles, I’ve always seen ipv4 and not ipv6!
Hell, my ISP seems to exclusively use ipv4 (unless behind nats they’re using ipv6)
Do you think a lot of people stick with the earlier iteration because they have been so familiar with it for a long time?
When you look at a ipv6, it looks menacing with a long string of letters and numbers compared to the more simpler often.
I am aware the IP bucket has gone dry and they gotta bring in a new IP cow with a even bigger bucket, but what do you think? Do you yourself or your firm use ipv4 or 6?
Noobie question, wouldn’t the ISP decide what your outgoing IPv6 address is? Like they do with IPv4? I mean no matter how many times I restart my router, my public IP remains the same so I always thought it was assigned by them.
They assign a prefix. For IPv4 this is usually a /32, or 1 single address, though it’s possible to assign larger ranges. I’ve seen businesses with a /28 on IPv4 for example.
The end device picks what IP addresses within the prefix are used for what. For instance, the server rack may use three IP addresses, the office one, and maybe the IoT network also gets one.
With IPv6 you should be getting a /56 or a /48. In other words, they pick the first 48 to 56 bits of your IP addresses, basically leaving 80 to 72 bytes for the end device to distribute amongst itself. You could give the first device address one and start counting up if you wanted to, but that’d come with the annoying edge case of needing to track what numbers are already in use. If you like a false sense of control, DHCPv6 is what manages this.
SLAAC (the “everything works by default” approach) requires a /64 (64 bits of local address space), so if you want to do routing (say, attach a wireless access point or a second router) and you don’t want to do IPv4 hacks that hide IP addresses from each other, you need a few networks. That’s why you get 8 to 16 bits of network space, so you can assign 256 to 65536 networks yourself in case you have weird requirements.
If your ISP assigns you 2003:123:def:abc::/48, then you can pick whether you want to assign 2003:123:def:abc::beef:cafe or any random address that starts with the ISP prefix. You have enough space to give every connection of every device on every WiFi network its own IP address every second of the day, but usually addresses are rotated only once per day.
The ISP picking the address range does come with a huge downside, and that’s that you can’t really use internal IP addresses anymore. To fix that, you can set up a so-called ULA. That’s basically a service anywhere on the network that shouts “hey, if you can’t, you can pick any address from fdef:abc:abc:abc::/96”. By default, devices will pick two addresses (one based on the MAC address and a temporary one), and you can use the one based on the MAC address to plug into your local DNS server.
That way, even if you switch ISPs to one that only does IPv4, you can still use a Pi-Hole at fdef:abc:abc:abc::123:456:789 as your DNS server. These ULAs are completely local, so they can’t be reached from the internet.
Though, just to be sure, you should generate a random ULA prefix (there’s an algorithm in the standard, but there are sites to do it for you) just in case you have bad luck and connect to someone else’s wifi who also thought it’d be funny to use fdef:cafe:babe:b00b::/96 as the local prefix. Completely optional, but best practice.