Why would you do that though when there are perfectly fine internal address ranges available?
If you drive around with a WiFi stumbler running, you'll run into networks with names like "UTAH DATA CENTER" and "SIPRnet", etc for the same reason.
Made me wanna climb out of my FBI Surveillance Van and have a word with them.
In that case there's never any chance it'll be needed by people using the public internet there, and never any chance it'll be used suddenly by a deployed internal service somewhere else from an outside vendor.
The default should reserve a single ip range and simply fail (with a nice message) if more are needed.
Classic merger "solution".
Company A uses 10/8 Company B uses 10/8, company A buys company B and orders new subsidiary B to renumber into 11/8 "All you have to do is change every first octet to 11"
If your ISP doesn't provide it, get one that does. They should allocate you a /56 by default per connection, if not something larger like a /48 if you have multiple locations.
Subnet the /48 for each connection, subnet each /56 into /64 subnets. reserve one of the /56's for site-to-site if needed.
Done.
How would you "simply add two top octets"? The address fields in the IPv4 header are a fixed size of 32 bits. Every time this is discussed, someone comes up with this suggestion to "just make the addresses longer and change nothing else", but there's no way to make the addresses longer without changing something else. And that's before considering compatibility with older hosts or routers; how would an old host talk to a new host, or two new hosts talk one to another with an old router in the path? In the end, what you'd have would be two separate networks, with some hosts being in both networks, which is exactly what we have with IPv4 and IPv6.
Yeah, it works well enough until it doesn't: I love when VoIP calls have one-way audio or when I have to map ports because the traversal method used by this P2P app is not working. When run at the ISP level it's even more fun: remember when wikipedia blocked the whole Qatar?
Screw DNS. Screw the recommendation to stay away from IP's. If it's important enough to be on the network, it's important enough to have a static IP.
And by "stupid addressing scheme" do you mean it's too big, or what? You can ignore all that stuff with mac addresses and make all your addresses go like prefix:subnet::1 prefix:subnet::2 prefix:subnet::3 if you want to.
Every networking problem in the world can be solved with more NAT or more encapsulation :)
https://www.cisco.com/c/en/us/support/docs/ip/network-addres...
In both cases RFC1918 was used throughout their global network and while not fully used, had become highly fragmented over time.
They didn't actually need the addresses to be routable from the public internet (that was the whole point of the VPN). I think the requirement was really a way of making sure they were unique. I'm sure they had several partners who used 10/8 internally.
In my work we use 10.0.0.0/8 but of course some people use the same at home even though 192.168/16 is way more common. In general I find 172.16/12 the least common in the field.
It just looks nicer to me which shows the power of Apple and how easily I am influenced.
And many are surprised to find that there are 172.* that are routable.
Still gives you fun issues though.