any body know of a website or software that will let you design a network?

[Charlie_M1]

for instance: in class i need to design a network that has this: 4 Class C networks (192.168.n.0)
Each network will have no more than 30 hosts
Assume the four networks have 4, 7, 3, 5 hosts respectively
Assume each network has its own networked printer
1 Class B backbone (172.16.n.0) (fast Ethernet)
All PCs will need to communicate
Only PCs in its own network can print to their printer
Design to be upgradeable:

So any software or websites where i build this with diagrams?

[see0emily0play]

I did research over the summer on wireless sensor networks, and we used a program called ns2 to simulate different networks.

Here's a link with information and how to download:

http://www.isi.edu/nsnam/ns/

I should let you know, while this program is extensive, it can be really frustrating to use. It's not very user-friendly, but if you can get by that, it's invaluable.