Application that detects bandwidth-using software/hardware?

[Bulleh]

Hello guys,

I noticed my internet connection got quite unstable lately (slow as well, for the most time), so I'm trying to find out whether it's something connection-leeching (like software, spyware my scanner can't detect, who knows, or maybe another device using bandwidth) or just the internet provider that's screwing up with my signal. I remember my brother using some sort of application that can analyze your internet connection and show everything that uses upload or download traffic. Anyone knows a program like this?
would be appreciated, tnx :)

[editline]01:43AM[/editline]

Didn't know the right keywords when I tried to google it, found them during writing this text though :>

[drummerundrcovr]

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