Networking Strategies

This section outlines some of the elements I use in my network to make my computing power more accessable and productive. It is currently under development. If you have any specific questions, please e-mail me.

Wireless Bridge   Dynamic DNS Names   VNC / Remote Desktop Connection               SSH and Secure Port Forwarding   Remote File Access Strategies   Jimbo's Network Specs

Wireless Bridge

Goal:

• Connect a network segment with up to 5 wired computers to another network segment wirelessly.

Example:

• A router is placed in the living room because that is where the cable modem is. A noisy storage server does not belong in the living room and requires at least a 100Mbps link to another machine to move files efficiently. The placement of the storage server would require wiring to be run inside the walls, which is too expensive. To solve this problem, we put the storage server and whatever computer needs to get at the files on a secondary router and link the two routers wirelessly.

Pros and Cons:

• Pro: makes physical placement of computers less important.
• Con: second router probably costs more than 2 PCI wireless-G cards
• Pro: computers on the secondary router can communicate between eachother at 100Mbps
• Con: computers on the secondary router share a 54Mbps connection to the main router and Internet
• Con: need to replace factory firmware on secondary router

Tools:

• (2) Wireless routers (we will deal specifically with Linksys WRT54G on this page)
• Internet connection
• At least one system to be connected by a wire
• At least one CAT5 cable (one for each system that needs a wire)

Steps:

1. Set up the main router. This is the router that will connect directly to the Internet, host DHCP and DNS services, and run the wireless network. It should be set up normally, no advanced configuration is needed on the main device.
2. Make sure your wireless network is set up properly. I generally recommend encryption on the wireless transmissions. I use WPA AES with a long key code.
3. Set up the secondary router. This is where things get tricky, and could dangerous for your hardware. You must replace the firmware on your router with a Linux based system called DD-WRT. DD-WRT will give you a lot more features than the standard Linksys firmware, but there is a small risk of ruining your router if the installation doesn't go well (i.e. you lose power, do things in the wrong order, etc.).
   • For newer routers (WRT54G v5 and later) you need to do extra work to get this done. The DD-WRT team is working on this now, so be sure to chek their website for the latest update on v5 and later support. For now, read the instructions found here. These are the directions I used, and I was up and running in about 20 minutes because I took my time.
   • Older routers can use the general directions found on the DD-WRT website
4. Configure the secondary (DD-WRT) router
   1. See the DD-WRT website if you can't figure out how to do any of these steps. I won't go too deep into them, as the configuration may change with newer versions of DD-WRT
   2. Connect to the secondary router with a cable, and make sure that you are not connected to your main router wirelessly.
   3. Log into the DD-WRT router config page (http://192.168.1.1 user: root pass: admin) and change its IP address to 192.168.1.2 so that it doesnt try to steal the address of your main router, and reconnect to it at http://192.168.1.2
   4. Then, shut off DHCP, DNS, and any other items that will confilct with the main router.
   5. Might as well set the WAN port onto the switch so you can use it for a 5th computer port. You wont be needing it because the main router is dealing with the Internet connection.
   6. Change root password if you want to
5. Create the wireless bridge
   1. On the wireless settings page of the secondary router, select "Wireless Client" mode, and fill in all the information about your main router's wireless network.
   2. Test the connection to the Internet, main router's config page, or a computer connected to the main router from a wired unit connected to the secondary router.

Notes:

• Remember that all the computers on the secondary network can talk to eachother at 100Mbps, but they share the 54Mbps link to the main router.
• Remember that your main router sees all computers on the secondary router as wireless connections, so if you set "no configuration access from wireless clients" on your main router, you will not be able to edit the configuration of the main router from any clients on the secondary router. Generally, this isn't a problem, but just something to be aware of.

Dynamic DNS Names

Goal:

• Create one address that points to your home network no mater how many times your IP changes.

Example:

• A person has a standard high-speed Internet connection which does not gaurantee that the connection's IP address will remain the same. This person wants to host some service (web site, VNC connection, FTP, game server, whatever), but cannot because he/she can't gaurantee an address for any time period. To solve this problem, we take a standard DNS name, such as phil.get-my-ip.org, to whatever IP address the connection is currently associated with. This is called Dynamic Domain Name Resolution or DDNS.

Pros and Cons:

• Pro: get to your network from anywhere in the world
• Pro: much cheaper then buying a static IP address
• Con: small security risk to your network if not handled properly

Tools:

• Free DynDNS account (there are other services, but this is the one I use and I have had no problems with them)

Steps:

1. Register for an account at the DynDNS website
2. Create a Dynamic DNS name, make it whatever you want so long as you will remember it
3. Set an IP to go with the name. It doesn't matter what it is just yet, we'll get to that.
4. Set up an automatic update so your DynDNS name always points to your home network. There are 2 ways to do this:
   1. Set up DynDNS's software. This is fairly simple, but requires your computer to always be powered on and connecting to the Internet through the connection you want to associate the DDNS name. The client runs on Windows or on Linux as an automatic service. I have used both, and have had no major problems with them. Both are lightweight and effective. The Linux version is a bit clunky to configure, but once configured it runs great and never needs to be touched again.
   2. Set up your router to update DynDNS automatically. If you have a newer Linksys router, you will find DDNS under the setup tab of your router configuration. Simply fill in your account information and it should update the DDNS name whenever the IP of your Internet connection changes. I am currently having issues with this method, but I believe I have traced the cause to outdated firmware.