Carrier Grade NAT

Mikael Abrahamsson swmike at
Tue Jul 29 15:23:48 UTC 2014

On Tue, 29 Jul 2014, Colton Conor wrote:

> How do you keep track of copyright violations in a CGNAT solution if 
> multiple customers are sharing the same public IP address?

You ask them to provide port numbers. If they can't, then you can't 
identify a single subscriber.

If law enforcement comes along without port numbers then you give them a 
list of subscribers behind that IP at the time. Use port block allocation 
and keep track of the blocks to reduce logging load.

Mikael Abrahamsson    email: swmike at

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