RTO mainly means Request Time Out

It occurs when we send request to the server and it does not give response. But it does not mean that we dont have internet connectivity sometimes RTO occurs because of delay by the responding server.

So RTO means not getting the response within a specified time frame by the server.

RTO occurs mainly due to traffic load congestion or due to disconnectivity of internet

RTO is like parameter which can make the evaluation of the called server to be available and if available will it respond to the specific time or not .

You can test it on command prompt

Just open command prompt and type:

Ex : ping www.google.com

If it response message appears Reply from and the associated IP

If it does not respond an RTO will occur