Can´t connect to SAP BPC Netweaver with Public IP

Hi experts.

When login to SAP BPC web admin, everything is ok with both private and public ip addresses. When login to SAP GUI with private IP address everything is ok too. But, when trying to login to SAP GUI with public IP address, it asks for client, user, password and language, but the "Login not possible (error in license check)" error message comes out.

Regards.