Hi, Leo. I don’t know if this is something you can answer or not, but I need
to know because I’m in quite a sticky situation. Does email coming from the
same IP address imply that even if it’s not the same computer it’s definitely
in the same country? It’s impossible for a friend of mine in one country to
have the same IP address as someone else in a completely different continent?
Right?
In this excerpt from
Answercast #14, I talk about how IP addresses identify the location of
computers and how it might not be exactly what you expect.
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Are country IP addresses always different?
No.
So, there are two different ways that this can happen.
- One, is a multi-country ISP.
There aren’t that many, but it’s possible. An ISP could certainly reuse IP
addresses and reassign them to different users as they login. That’s what DHCP
does: the dynamic protocol that assigns an IP address to you when you connect
your computer.
Typically, yes, they’re all in the same country. But I could certainly
envision an IP or ISP that services more than one country. Since we
don’t know what country you’re talking about, I can’t say for sure that this isn’t
the case.
You did say, “Definitely.” And I can’t say definitely.
- Two, is Proxy Servers
The other scenario is one that’s slightly more likely and that is proxy
servers.
If you send email through a proxy server of some sort (or if you use a web
mail service of some sort), then the IP address that is in the email could well
be that of the proxy service (or of the web mail service) and not the IP
address of the physical location of the computer from which the person is
sending email.
IP address location is not definite
So, there are scenarios there where the IP address associated with
the email:
- Not only isn’t necessarily in the right country
- But it’s not even associated with that user in any way; in any direct
way.
So, in absolute terms, No. We cannot infer that ‘absolutely’ the same IP
address means the same country. There’s definitely a lot more information
that’s needed before you can even come close to saying what’s really going on
here.
In general, sure, it’s likely: it’s common. It is most often the case that
the IP address does infer a specific country.
But, in absolute terms, there are ways around that, and ways that you cannot
count on being used, or not being used, to obfuscate exactly where somebody
resides.
