Secure EC2 Instance Traffic Monitoring and Inspection

Answer: A.

Option A is CORRECT because a host-based intrusion detection system can be used to monitor and inspect packets for security threats.

Option B is incorrect because AWS Shield is used for DDoS protection and would not assist with packet inspection.

Option C is incorrect because VPC Flow logs let you capture and log data about network traffic, but it cannot conduct packet inspection.

Option D is incorrect because the logging solution is not available for Network Access control lists.

For more information on AWS Security best practices, please refer to the below URL:

Out of the given options, the most suitable option for monitoring and inspecting traffic packets for security threats for EC2 instances in AWS is to use VPC Flow Logs.

Here's an explanation of each of the options and why VPC Flow Logs are the most appropriate:

A. Use a host-based intrusion detection system: A host-based intrusion detection system (HIDS) monitors and analyzes activity on individual hosts or devices, such as EC2 instances. While HIDS can provide valuable security information, it may not be scalable for larger environments with multiple instances. Additionally, it requires installation of agents on each instance which may add to the management overhead.

B. Use AWS Shield: AWS Shield is a managed Distributed Denial of Service (DDoS) protection service. While it helps to protect against DDoS attacks, it does not provide the level of monitoring and inspection required to identify other types of security threats.

C. Use VPC Flow logs: VPC Flow Logs is a feature that enables logging of network traffic to, from, and within Amazon VPC. It can be used to capture information about IP traffic going to and from network interfaces in an EC2 instance, including source and destination IP addresses, ports, protocols, and packets dropped due to security group or network ACLs. This information can then be used to detect potential security threats, such as malicious traffic or network intrusion attempts.

D. Use Network Access control lists (NACLs) logging: NACLs are used to control traffic at the subnet level in AWS. While NACLs can be used to filter traffic based on IP address, protocol, and port number, logging is not sufficient for detecting security threats.

Therefore, VPC Flow Logs is the most suitable option for monitoring and inspecting traffic packets for security threats for EC2 instances in AWS.