The ping, technically correctly the roundtrip delay, can be explained as a time range during which a data packet sent from your end device (desktop PC, laptop, cell phone) travels via the Internet to the measuring server of the CTU-NetTest tool and back. Ping (delay in the data networks) is being stated in ms (milliseconds). High values of the roundtrip delay can prevent using services in real time (e.g. TV or VoIP) and are also often one of the reasons why the actually achieved download and upload speeds decrease. In general, full utilisation on the IAS provider’s network causes increase of the ping value and vice versa. During measurement of the roundtrip delay via ping, protocol of ICMP network layer is being used.