Network performance and security are playing a very important role in current Internet environment. Most network security systems have been focusing on edge systems such as servers, firewalls, and intrusion detection systems. Another target could be attacked is “network routing protocols”. Network routing protocols are used to create and maintain routing information in order to forward packets. Once routing protocols are under attacks, routing information could be modified into incorrect situation or altered as very large size and thus adversely affects the packet forwarding and router function. In this paper, we examine the performance and security issues of various existing routing protocols including RIP, OSPF, and EIGRP. An experimental network environment is built to implement various routing activities which are monitored and analyzed via logging and snmp trap analysis systems. Various routing performance metrics are evaluated and analyzed via the logged and trapped information. Finite state automata are designed to trace the routing behavior and detect malicious routing table updates.