IP Technical question

[Ian Batten]

Richard Clayton wrote:
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> In article <114b9bdc0901242359p3e2224d9j64f5d2502648435b@mail.gmail.com>
> , Stop Common Purpose <stop.common.purpose@googlemail.com> writes
> 
>>    As I understand it, an IP address may be assigned to hundreds of 
>>    individuals.
> 
> I assume you mean when NAT is used (or do you mean over time ?)
> 
>>    Is this correct?
> 
> It would be unusual to have quite so many machines behind a single
> NATted IP address.

When I used Vodafone GPRS heavily, they appeared to have their entire 
userbase behind two IP numbers: I had a special listener on my mail 
machine to bodge around the limitations of my phone, and I was able to 
use something like a /30 to limit access to it.

I've not had cause to look at O2 as closely, as my iPhone is a much 
better behaved IMAP client, but a swift look at the last week's logs 
reveals that the O2 3G network is scarcely more profligate with addresses:

> -bash-3.00$ cat /var/log/mail/cyrus.log* | grep 'igb.*User logged in' | egrep -v 'bethere|127.0.0.1' | awk '{print $10}' | sort | uniq -c
>    8 [82.132.136.177]
>   22 [82.132.136.178]
>   17 [82.132.136.180]
>   30 [82.132.136.181]
> -bash-3.00$ 
> 

And that's before, as other people have mentioned, we account for 
proxies.  We use a proxy for over a thousand users; I think last time I 
was there the entire Kawasaki operation of my employer was behind 
perhaps a couple of machines.

ian