Depending upon who you ask, the IDS may be a simple audit trail process, or a filter process using a traffic control system, like screening routers, packet filters, firewalls, etc. Some people use IDS to mean a logging utility. This paper studies improving Internet security with Network Security combined authentication and intrusion detection (NS-IDS) secure data transmission in such MANETs. Security is deployed to work with intrusion detection systems (IDSs) to alleviate the shortcomings of uni-modal biometric systems. Since each device in the network has measurement and estimation limitations, more than one device needs to be chosen, and observations can be fused to increase observation accuracy using for the system decides whether user authentication (or IDS input) is required and which (or IDSs) should be chosen, depending on the security posture. The decisions are made Network in fully secured manner by each authentication device and IDS. Simulation results are presented to show the effectiveness of the proposed scheme.