What is Nmap designed to do in network security?

Nmap, short for Network Mapper, is a powerful open-source tool commonly used in the field of network security primarily designed for network discovery and security auditing. Its main functionality includes mapping out the network by discovering hosts and services on a computer network, thus allowing security professionals to visualize the network architecture.

By generating a network map, Nmap identifies active devices, their IP addresses, open ports, and the services running on those ports. This provides crucial information for assessing the security posture of the network, as it helps to identify potential vulnerabilities that could be exploited by attackers. This mapping capability is essential for planning security measures and performing audits.

The other options, while important aspects of network security, do not accurately describe Nmap's primary intended function. Encrypting sensitive data refers to protecting information from unauthorized access, which is not within Nmap’s capabilities. Monitoring network traffic involves analyzing data packets transmitted over the network, normally handled by other tools specialized in traffic analysis. Providing firewalls refers to setting up barriers to block unauthorized access while allowing legitimate traffic, which is again outside the scope of what Nmap is designed to do.