I have a server in USA. I'm from Canada. Some of my users around the world are reporting download speeds of 10KB-30KB/s, even some users who are in USA. Downloading from my place gives me around 500KB/s. The server is a file download server. It has plenty of CPU, RAM and the hard disk is fast enough. I have a 100MBps port to the internet which is never completely used. I'm on cogent. I was not aware of this problem until users started fleeing away.
How do I do to find the problem? Is a traceroute from the users' computer helpful to find the bottleneck?