Lots of people would think what the address 127.0.0.1 is when first seeing this address. In fact, 127.0.0.1 is a loopback address which refers to the local machine. It is generally used for local testing. When typing ping 127.0.0.1 on local command console, it will send network packets to local IP/TCP layer to test whether IP/TCP works properly or not. To those who are used to use localhost, it is actually mapped to 127.0.0.1 by default. There are hosts files in the system which store this mapping. Hence normally these two can be interchanged.# localhost name resolution is handled within ...