You in a small town where there is no computer or electronics store, but you need a local area network set up fast. Being a McGuyver type, you have a basic knowledge of electronics. There are four old computers, seven modems, plenty of wire, and old electronics you can borrow parts from.You always have a soldering iron solder and wire cutters with you. What do you do?

You will make some modified telephone wire to all the modems to work with each other. You will need to make them long enough to go between the server modems to the client machine. You have two diagrams to choose from to power the lines between the modems.

Screenshot from 2013-09-22 17:31:51

Source for the schematics!

With the wiring done, now we can talk about setting up the computers. External modems are easier to setup but involve lots of cabling. We will try to do this with internal modems. There are three kinds of modems which are winmodems, null modems, and true modems. Winmodems have less electronics and depend more on software and use of the computer itself to function. True modems have more electronics. but do not depend on the cpu per se and are easier to program. Null modems are just special rs232 cables for short distances with the right serial or rs232 interfaces (no regular modems and phone line are necessary). Now to go look in the parts box to see what we have.

Let’s see now for four computers, we will need seven modems. Huh? One computer will have four modems. One for the dial up internet connection (it can plug directly into the wall phone plug without the battery or other power source) and three others to connect to three of the remaining pc’s. Of course each pc will have a modem to connect to the pc with four modems which we will call the server, You call call this a star network configuration.

How will they all talk to each other? Actually the server will act as both a server and a hub/concentrator (telephone pbx sort of) for our configuration.The three other computers will become the clients or nodes. But we need a special way for the machines to talk between each other. We will use what is know as slip (serial line internet protocol).
———————————- Coming soon. ——————————————————–