Quic kind of has 3 windows: Per stream and per connection flow control windows, which kind of indicate how much data the peer may send on a given connection be

Quic kind of has 3 windows: Per stream and per connection flow control windows, which kind of indicate how much data the peer may send on a given connection before it gets a window update. Those windows also indicate how much the server is willing to store in its receive buffers, since the updates are likely sent when those buffers are drained. A congestion window, which indicates how many low-level packets and data in them can be in-flight without being acknowledged. Those also account for retransmissions, and packets which do not necessarily contain stream data.