How to allocate ip addresses in subnets?

Question

Computer networks

it is necessary to paint the ip addresses of subnets and devices, as well as a brief routing table for R1.
can anyone explain?

Answer 1

R1 network 192.168.1.0/25
R2 network 192.168.2.0/25 interface looking at R1 192.168.0.2
R3 network 192.168.3.0/24 (or 192.168.3.0/25 + 192.168.3.128/25 since object 2) interface looking on R1 192.168.0.3
R4 192.168.4.0/25 interface looking at R1 192.168.0.4
The routing table for R1 will be something like this.
Destination Gateway
default external access to the Internet if there is
192.168.2.0/25 192.168.0.2
192.168.3.0/24 192.168.0.3 192.168.4.0/25
192.168.0.4
assigning each of the interfaces its own address, then the routing table will have a network binding not to gateways but to interfaces.
There are many options here, you can generally take any networks from the ceiling if there is no data, then there is no fundamental difference what to use, at least run R1 in router mode and give each interface its own range, and R2, R3, R4 in switch mode.
For explanations in any routing textbook, I recommend the CCNA course.

Answer 2

Estimate the number of hosts (allow for possible growth) in each network - it will become clear which subnet mask to take.