How to improve performance on a network with multiple subnets?

Question

Network administration

Hello, I am writing a course paper on optimizing the operation of an enterprise network, I encountered the following problem:
In the first picture, the speed of copying a file using the smb protocol from one workstation to another will be approximately equal to the bandwidth of the switch interface.
In the second picture, the ip-packet from the first workstation will go to the router interface (100Mbps), and if the router does not drop it according to some rule, then only then the packet will be sent to the second workstation.
In this case, a router with a 100Mbps interface will be a bottleneck when sending packets from one network to another

. What should I do if I have about 100 workstations and I need to actively forward packets from one network to another?
update: Even if you install a router with a gigabit interface, this will not improve the situation much, while copying large files between networks, the speed will be reduced relative to the speed of copying within the same network.

Answer 1

In this case, you need not an L2 switch, but an L3 switch and route subnets on it, and not on the router. For simplicity, it is acceptable to use the /16 prefix on the switch.

Answer 2

As an option - to aggregate the channel between the router and the switch