are the network admins forced to give to the authorities users real ip
Yes.
Firstly, it is theoretically the duty of all citizens to help the authorities resolve cases of criminal behaviour. To know that you have useful information and to deliberately withhold it is an offence in its own right in most jurisdictions.
Secondly, where there are also legal instruments - including subpoenas - which can force the release of even business/company/client confidential material to a court or to the authorities.
PM
