The following image represents how a physical terminal (for example: VT100) was connected to a computer running Unix (for example: PDP-11):
Notice the components highlighted in blue, which shows that the terminal is connected to the computer through a serial port (the image says "UART" instead of "serial port"). So basically the terminal has a serial port that is connected though a wire to a serial port on the computer (the image also doesn't show a component for the terminal serial port).
You can change the baud rate for the serial port on the terminal side, also you can change the baud rate for the serial port on the computer side (see here).
Now the following image represents how a virtual terminal is implemented on a modern Linux/Unix machine:
Notice the components highlighted in blue, which shows that the terminal emulator is connected directly to the line discipline without using two "virtual serial ports".
Now my question is: is this image (the virtual terminal implementation) shows the entire components, or should a "virtual serial port" exist after the terminal emulator and another "virtual serial port" should exist before the line discipline?
If these two "virtual serial ports" do exist, can you also change their baud rate also?
I got these two images from here.