An Intrusion Detection System (IDS) is a software or hardware system that monitors network traffic for malicious activity and alerts the administrator of any potential threats. An Intrusion Prevention System (IPS) is a software or hardware system that not only detects but also blocks or mitigates the malicious activity. Both IDS and IPS are essential for securing a web application in a cloud environment1.
A web proxy server is a server that acts as an intermediary between the client and the web server. It can provide caching, filtering, and authentication services, but it does not offer IDS/IPS functionality. Therefore, option A is incorrect.
Load balancing using SSI (Server Side Includes) is a technique that distributes the workload among multiple web servers by inserting dynamic content into web pages. It can improve the performance and availability of a web application, but it does not provide IDS/IPS protection. Therefore, option B is incorrect.
Implementing IDS/IPS agents on each instance running in that virtual private network is a valid solution for providing IPS protection for traffic coming from the internet. The agents can monitor and inspect the network traffic on each instance and block or report any suspicious activity to a central management console. This can prevent attacks from reaching the web application or spreading to other instances in the same network. Therefore, option C is correct.
Implementing dynamic routing is a technique that allows routers to select the best path for forwarding packets based on network conditions. It can enhance the reliability and efficiency of a network, but it does not offer IDS/IPS functionality. Therefore, option D is incorrect.