Trace network traffic paths using Network Utility on Mac
Messages you send across the internet usually pass through other computers on the way to their final destination.
Use Network Utility to follow the path a message takes as it travels through the network from computer to computer.
On your Mac, open the Network Utility app , located in the /System/Library/CoreServices/Applications folder.
Type the domain name or IP address of the final destination and click the Trace button.
For help interpreting the results or to see how you can use the underlying traceroute command to fine-tune your troubleshooting, open Terminal (in Applications > Utilities), then type man traceroute at the command line.