How to upgrade the old Internet cafes in a 100-megabit intranet to a new gigabit network, and what equipment is needed? ...

As far as I know, the Super Category 5 cable also supports Gigabit. The landlord can use a super-category 5 line to do the experiment. It is used to connect two machines with Gigabit network cards. Of course, this line is interconnected by two machines, so it is necessary to make a cross line (a 568A standard and a 568B standard) to test the file transmission speed. Of course, your line should be longer, which is more convincing. Eighty meters should be enough. If the measured average transmission rate is 100MB/s, I think this is enough to show that Gigabit is supported, so your network only needs to replace the switch and the network card of the machine.