Pong!
The round trip time is the time it takes for a IP packet to travel from our server to your computer.
We just tried to ping you, but something blocked our ping. Most likely it was your firewall or a proxy.
Since our ping packets never reached you, have can't report a round trip time,
and we have no statistics to show you.
However, we do not recommend that you turn off your firewall just to have some
statistics reported.
Here is IP address we tried to ping.
How ping works
- Our server generates an ICMP protocol data unit (PDU)
- The ICMP PDU is encapsulated in an IP datagram with the source (our server) and destination (your computer) IP address in the IP header.
At this point the datagram is referred to as an ICMP ECHO datagram. - Our server notes the local time on its clock as it transmits the ECHO datagram towards your computer.
- Your computer receives the ECHO datagram
- Your computer discards the ECHO datagram and constructs an ICMP ECHO REPLY datagram.
- The ECHO REPLY is sent back to our server, ususally on the same path the ECHO datagram went, but not necessarily.
- Our server receives the ECHO REPLY from your computer and again notes the time on its local clock.
It then computes the time difference between when the ECHO datagram was sent and when the ECHO REPLY was received. - This time difference is called the round trip time.