What programs are there for designing and immediately testing a LAN?

Question

Software and Internet Services

I want to find a program for designing a future / existing local network and so that you can immediately check the speed of data transfer, packets, commands from cmd (for example, ping xxx.xxx.x.x), in general, various commands)
The meaning is this: you need a network design program for the future, testing it virtually in order to eventually realize it physically

Answer 1

how do you imagine the speed test?)
And so, GNS3 analogues. Who knows what?