any one can help me ?

[easa0562]

You are to design a computer network for a retail company which has been assigned an IP class full network of 201.20.20.0; the company to have several locations in City2, City3 and City4; the company headquarters in City1.
In City2 the company has two branches, three in City3 and one in City4. The company is growing and more branches are to be open in the next 5 years.
Each branch shall have a maximum of 10 stations.
You are to design the network for the company by including all the necessary hardware (routers, switches, hubs, modems, cables, etc..).
Draw the topology of the network.
Assign IP addresses to all interfaces on the routers.
You need to assign IP addresses for the stations.

[JorgeM]

Your first task is to take care of subnettting the network ID of 201.20.20.0. If you do not know how to calculate this manually, there are a lot of online subnet calculators.

Just to get you going, if you apply a /28 (255.255.255.240) mask, you will be left with 16 subnets with a max of 14 hosts per subnet. You cannot apply a /29, because this will limit you to a max of 6 hosts per subnets. The /29 gives you the following 16 subnet IDs:

201.20.20.0
201.20.20.16
201.20.20.32
201.20.20.48
201.20.20.64
201.20.20.80
201.20.20.96
201.20.20.112
201.20.20.128
201.20.20.144
201.20.20.160
201.20.20.176
201.20.20.192
201.20.20.208
201.20.20.224
201.20.20.240

You will need to pick the topology for the WAN (most likely a partial or full mesh for redundancy) and a star topology for each local area network.

Using the information in this response, you should be able to go back and start working on a design and IP scheme for all of your devices.