> Basically my ISP router would receive data at full speed, while internally I would have a lot of dropped packets. This is not how this works. The other end o

> Basically my ISP router would receive data at full speed, while internally I would have a lot of dropped packets. This is not how this works. The other end of your zoom call doesn't go "hey the person I'm talking to is on a 700mbits line, so that's how much data I'll send." By that logic you could extend this to the network of your isp, which is probably 10 or 100gbits, so you should have a lot of packet loss where the transition from 10gbits to 700mbits happens. And it's not even clear how the other peer could even know how fast your internet connection is, or the internal network of your ISP. That is what congestion control is for. Your peer can't know your modem's connection speed nor your LAN's speed. Software will simply observe how fast it can send data before packet loss starts to happen. This obviously requires that the there is some sort of feedback by the peer you're talking to. If you're using TCP, the OS will do that for you for free. With UDP, you have to implement that logic yourself in your application. And that's why it doesn't matter where the bottleneck is, it could very well be somewhere "in the middle" between two ISPs.