[strenholme]

“There is only one 10.0.0.0/8”

Also:

- There are 16 172.{16-31}.0.0/16s (I used 172.23 because Docker uses one of these)

- There are 256 192.168.{0-255}.0/8s

And that’s just what RFC1918 gives us. There are other private subnets defined in newer RFCs.

I like IPv6 but it caused issues with browsers accepting my Letsencrypt certs on my website, so my website is now IPv4 only.

“Announcing that address block using BGP gives you a permanent block of routable addresses that follows you from ISP to ISP.”

Enough people have done this that BGP networking has become a real mess at the ISP level. Can BGP really handle every person in the world doing this?

[gerdesj]

Class B or the 12 block is 172.16.0.0/12. So: 10/8, 172.16/12, 192.168/16.

[db48x]

Yes, I know that there are other private subnets in IPv4. My comparison was specifically between IPv6 ULAs and 10.0.0.0/8 specifically because of the size. You won’t have to renumber your networks when you grow in size because 2⁷² addresses is enough for just about any organization.

> Can BGP really handle every person in the world doing this?

Eh, probably not. I did say that it wasn’t for everyone. You have to fill out a form, and then they announce to the world that you did it. And if you configure your BGP announcements wrong you’ll get laughed at by everyone who watches those things. Most people can’t handle it.

On the other hand, the VP of Network Operations at the ISP I used once promised that they’ll honor BGP announcements even from residential customers. I guess once it’s automated that it doesn’t cost them anything extra. Could be a fun hobby.

And if enough people do it then we can simply improve BGP. Anything we invent we can improve, right?