Mobile Ad-Hoc Networks (MANETs) consist of a collection of wireless mobile nodes which dynamically exchange data among themselves without the reliance on a fixed base station. MANET is more vulnerable to different types of attacks and security threats because of its characteristics of mobility and dynamic nature. Intrusion means any set of action that attempts to compromise the integrity, confidentiality, availability of resources. We are implementing EAACK secure acknowledge based IDS to remove the drawbacks of Watchdog. By using the schemes of EAACK we propose a cooperative, dynamic hierarchical intrusion detection architecture that addresses these challenges while finding specific and conventional attacks in MANET. The structural design is organized as a dynamic hierarchy in which data is acquired at the leaves and is incrementally aggregated, reduced, and analyzed as it flows upward toward the root. To maintain communications effectiveness, the hierarchy is automatically reconfigured as desired using clustering techniques in which cluster heads are selected based on topology and other criteria.