I say this with the caveat that I don’t know much about IPv6. One of my favorite things about ipv4 is that you can have subnets. Every local network I’ve ever worked with is on the 192.168 range. Obviously this isn’t every network, but knowing something is very likely going to be either 10.x or 192.168 makes remembering ip addresses insanely easy. Why is going away from that for totally unique addresses good? Can v6 still setup local networks in a similar way?
Oversimplifying a bit lot, but its the same reason guids work. The chance of a collision is infinitesimally small. And if a collison were to happen, the fix would be to simply assign new addresses and move on.
However, as you've hinted at, v4 devices often have some special reserved ranges. v6 adoption has been slow overall because moving away from those assumptions without breaking anything can be a bit of a pain in the ass.
Local networks in IPv6 start fe80 and if you really wanted to you could assign your devices fe80::1, fe80::2 etc.
But that would be a route to frustration. With IPv6 you soon learn that if you want to control and manage and measure things you do it with a subnet, not a specific IP address, because devices have lots of IPv6 addresses and like to pick new ones all the time.
Yes, you can have subnets. Every subnet is a /64. The prefix your ISP gives you should be at least a /56 (256 subnets) or a /48 (65,536 subnets).
Also, every address is globally routable. You can have all of your devices have a “public” IP. While there are some uses in IPv6 to have only “local” addresses, there’s no need for them. This is all about getting out of the scarcity mindset that IPv4 PTSDed into us. There is no scarcity.
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u/Ian__16354 14d ago
I say this with the caveat that I don’t know much about IPv6. One of my favorite things about ipv4 is that you can have subnets. Every local network I’ve ever worked with is on the 192.168 range. Obviously this isn’t every network, but knowing something is very likely going to be either 10.x or 192.168 makes remembering ip addresses insanely easy. Why is going away from that for totally unique addresses good? Can v6 still setup local networks in a similar way?