System Security: For the sake of ensuring the safe operation of the enterprise system, the Nseer Open Source ERP will supplies a special module of management of security control in order to guarantee the safe operation of thousands of modules within the whole ERP system. The management of security control of this application layer is more important, especially for those internet-based systems (Nseer suggests the enterprises to adopt the security solving plan of Virtual Private Network (VPN) form the third party to ensure the safe operation on the Internet. The basic functions of the system security of Nseer Open Source ERP: the management of the users of developing staff, maintenance staff, users, license for developing and maintenance staff and users, visit inquiry, data backup and recovery and others.