Basic Network Layout
This page is to assist people who are new to Cable Modems, Routers, Networking and Internet Connection Sharing or would just like to expand their knowledge in those areas.
You should know that in a domestic setting, (at home) sharing your Internet Connection with people that live in your home is perfectly legal. It is not usually legal to share it with people outside your home. An example would be for you to willingly provide Internet access to a neighbor either by a wired or wireless connection. If you use a wireless router it is your legal responsibility to secure it in a way that does not allow unauthorized access. On wireless routers, I usually activate MAC Address Filtering and configure it to deny access to all except those addresses listed. For most private homes, this would be adequate security. You can enable WEP, WPA, WPA2 or WES but you should know that these will slow your speed on the internet because your transmissions have to be encrypted and decrypted. Regardless of the security you choose, you should know that all information you submit over the internet by wired or wireless connections could possibly be compromised. Choose carefully who you send personal information too and make sure your on a secure connection. This is known by the beginning of the URL you are connected to. HTTP is NOT secure, HTTPS IS secure.
To setup a small network with internet access in your home I recommend using a Router and doing the following: The image above is intended to assist in the proper physical configuration.
All of that should have gone well. You should now be able to access your Router from any of the computers on the network by typing in the Routers IP address in your browser. If you can not access the Router, you need to look at the configuration of any software Firewalls on the computers to make sure that the Firewall is not blocking access. There are too many different configurations to offer any direction for this so check your Firewall help file to make sure it is properly configured. http://192.168.1.1 would be the default address for a Linksys Router and many others. It should ask for a username and password. On a Linksys the username is left blank and the default password is "admin". Now probe around in there to locate and change the password. On a wireless unit, locate the wireless section and change the default channel and the SSID. If there are other Routers in your neighborhood they can cause problems for each other if they are on the same channel. There is a freeware program called NetStumbler that can be installed on a wireless computer and will help identify used and unused channels in your area. It can be downloaded from the MajorGeeks website.
On a Wireless Router, I recommend setting up MAC filtering. You will need the MAC address of each computer that you want to allow to connect through the wireless portion of the Router. Before activating the MAC Filtering get your MAC address from the wireless computers after they have connected to the router by going to "Start" > "Run" then type "cmd" and hit enter. This will take you to the Command Prompt. At that prompt type "ipconfig /all" and hit enter. The wireless adapter should be identified and will have the MAC address listed as the Physical Address. The sequence will be alpha numeric in the following format 00:00:00:00:00:00 They need to be entered in the MAC address list and then check the spot to "Deny all except" and save the changes.
You should now be on the internet with basic security in place. You should also have a software Firewall and Anti-Virus on each computer. I don't recommend using the Windows XP built in Firewall. It provides almost no security compared to others like ZoneAlarm and BlackIce. I also recommend the use of Anti-Spyware software like AdAware or Spybot Search and Destroy. All of these software packages can be downloaded from the MajorGeeks website.
It's important to know that whenever you change the first device connected to the cat6 ethernet cable from the Cable Modem, usually the router, you need to go through the Startup Sequence again beginning with step 3 above. Even if you are just connecting your computer directly to the Cable Modem for diagnostic purposes you MUST do the restart procedure. The Modem remembers the MAC address of the first device connected to it so to clear that MAC address and allow a new device to be connected and configured there, a restart of the Cable Modem is required.
If you're having intermittent connection problems with your wireless machines you should be aware of the following: