Machines inside of your network can be partially concealed through IP masquerading (the version of Network Address Translation most used in Linux).

CNN: Analysis: Linux security

Google also saves searches tied to the network address of Mr. Brand's computer, which it makes anonymous after 18 months.

WSJ: Google Agonizes on Privacy as Advertising World Vaults Ahead

It outlined how the Cartoon Network functioned, the address of a call center and one of the service's pager numbers.

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