In network troubleshooting, what does 'ping' do?

In network troubleshooting, 'ping' serves the essential function of testing connectivity between two networked devices. When a ping command is executed, it sends Internet Control Message Protocol (ICMP) Echo Request messages to the target device, which then responds with ICMP Echo Reply messages. This interaction confirms that the target device is reachable over the network, and it provides information about the responsiveness and latency of the connection. Monitoring the round-trip time taken for the echo request and reply helps determine how quickly data can travel between the two devices, thereby offering insights into the health of the network connection.

The other options fail to accurately define the primary purpose of the ping command. Measures of internet connection speed, vulnerability scanning, and identifying IP addresses are aspects of network management and troubleshooting but are not functions performed by the ping command itself. The ping utility specifically focuses on connectivity tests rather than assessing speed, assessing security vulnerabilities, or resolving IP addresses.