Which tool is used to monitor the target IT infrastructure to discover devices connected to the Internet along with their details such as the operating system used, IP address, protocols used, and geography?

• A. Censys
• B. Shodan
• C. Nmap
• D. ZoomEye

Answer: (A)

Inventorying internet-facing assets by collecting banners, certificates, and service metadata to map devices, their operating systems, IP addresses, protocols, and geographic location.

Censys does this by continuously crawling the Internet and building a searchable database of hosts and the services they expose. It aggregates details like open ports, protocols, and OS information inferred from banners and certificates, and it links each host to geolocation data. This makes it a natural fit for monitoring an external IT surface: you can search for devices by OS, port, protocol, or region and observe how the landscape changes over time. While other tools offer similar visibility—Shodan and ZoomEye provide internet-wide search capabilities, and Nmap performs direct scans on a target network—the emphasis here is on a platform built for ongoing, broad visibility and historical tracking of internet-connected devices, which is what Censys specializes in.