Diagnosing slow downloads

Hi folks. I'm currently downloading a game update for my Xbox. While the Xbox network speed test says the connection goes to 600Mbps, the game itself downloads at roughly 6Mbps.

There's a decent likelihood it's not the router's fault, but at the same time, this is showing me I don't know how I would diagnose the problem. What tools do I have to figure out what's going on? For instance, is there any way to tell if there is packet loss upstream or something like that?

your speed test probably doesn't use the same server as the one serving the game update.

if it's a very recent update, you're not the only person DLing it. hence the digital traffic jam.