Glossary
What is Ping?
Measures network response time using ICMP packets. No response alone does not show that a website is down.
Ping uses replies to ICMP Echo requests to examine network round-trip time. Read the number of replies, packet loss and variation in delay together. A server-side measurement reflects the path from the application server to the target, rather than the connection from your own device.
Example
In an example check sending four Echo requests, received replies can be used to calculate delay and packet loss. No actual measured values are presented here.
Common issue
Some networks block or limit ICMP, so missing ping replies do not prove that a site is offline. Receiving ping replies also does not prove the web or mail service is working.