The question mentions that this is not hardware specific, however different platforms have different switching latencies and switching modes.
Cut through
switching is the fastest but lets through fragments.
Fragment free
is the second fastest and makes sure that frames are at least 64 bytes meaning they are not runts which is one of the signs of collisions.
Store and forward
is the slowest but does not send frames onward that contain errors such as CRC errors.
Your questions contains nothing on distances. If there is a significant distance between switch 1
and switch 4
that would have to be accounted for. If they are right next to each other, each switch should not add much latency since they generally forward frames immediately without them getting stuck in large buffers.
Latency is subjective, for a high speed trading firm, 2ms could make a huge difference. For most of us 2ms is not enough to worry about.
I would not worry about latency in this case unless I had a very specific use case.