Task:: Create a network Topology Setup in such a way so that System A can ping to two Systems System B and System C but both these systems should not be pinging each other without using any security rule e.g firewall etc .

We have initial environment as shown in pictures

System A

System B

System C

We manually assign the ips to System A , B and C as 192.168.1.1 ,192.168.1.2, 192.168.1.3 as shown in below pictures . We can clearly see the routing table of each Systems as shown below

For System A

For System B

For System C

We have to create the rules in the routing tables in every systems to achieve the given task situation

Adding a rule in the routing table of system A.

Adding a rule in the routing table of system B.

Adding a rule in the routing table of system C.

After all setup we can see System A can ping System B and System C

We can see System B and C can ping to System A

We can check even System B can’t ping to System C and vice versa

Conclusion :

System A is pinging system B and system C successfully. Whereas system B & system C unable to ping each other.

By setting the netmask as 255.255.255.252 for system A, it can ping 4 IPs in its range. We changed the IPs such that system B & system C come under the network of system A, but system B & system C do not belong to the same network as their netmask is set to 255.255.255.254 their network contains only 2 IPs.