On 12/4/11 8:22 AM, Hadriel Kaplan wrote:
So you tell me how safe picking a specific RFC 1918 address space is. There are ~100,000 enterprises with over 100 employees just in the US, and ~20,000 with over 500 employees in the US. Obviously my company is a tech company so it's probably not "normal", but still it seems obvious enterprises use random 10.x.x.x and 172.16/12.
AFAICT, it *isn't* safe to use these addresses if and only if these enterprises *also* use equipment that can't deal with 1918 addresses on their external interface. For example, your machine taking a 10.2xx.xxx.xxx address isn't a problem in and of itself because the NAT in front of you is translating. The issue only arises if the Carrier Grade NAT in front of you is on the other side of equipment that *can't* handle that portion of address space on the outside.
Now, I don't know if that means it *is* safe. I don't know how many enterprises talk to CGNs and wouldn't be able to deal with a particular block of 1918 addresses on the outside. That's the question I'd really like an answer to but haven't seen yet.
pr -- Pete Resnick<http://www.qualcomm.com/~presnick/> Qualcomm Incorporated - Direct phone: (858)651-4478, Fax: (858)651-1102 _______________________________________________ Ietf mailing list Ietf@xxxxxxxx https://www.ietf.org/mailman/listinfo/ietf