SUMMARY
Enterprise network (EN) supports thousands of users, and interconnects many networks. EN integrates different operating systems and hosts hundreds of servers that provide several services such as web applications, databases, E-mail, and others. Security threats represent a serious problem to EN. They try to damage enterprise confidentiality, integrity, and availability. Security provides protection against attacks, hacking, and data theft. In this paper, we propose a security model (SMEN) of EN. The proposed model provides security at different layers. It integrates both hardware and software security solutions. We perform a defense evaluation for the proposed model The results show that SMEN was able to detect and prevent all attacks and malwares that were induced by the framework Metasploit. Performance evaluation shows that applying proposed model has a little negative effect on bandwidth utilization and hence on network performance.