by Dave Dockery
I would like to Cyber Mentor a willing victim... I mean mentee. I quickly step them through the process of invoking and configuring Microsoft NetMeeting. I find out their IP address, and I initiate a NetMeeting call to them. However, I cannot complete the call. Their firewall blocks me. In its zealousness to protect them, it has blocked me, a guy wearing a white hat, from helping them. In order for me to be successful, I'm going to need to find a way to tunnel through their firewall.
What if I could prepare my firewall to accept their call? What if I had them initiate a NetMeeting call instead of me? If they initiate a NetMeeting call to a particular IP address, then their firewall will pass through any responses from that same IP address. That is the secret of Cyber Mentoring.
Fortunately, you don't need to thoroughly and completely understand the previous paragraph in order to make Cyber Mentoring work, but that is the secret. All we have to do to make this work, is to figure out a way for the cyber mentor's computer to recognize a NetMeeting call and to pass it on to the Windows operating system. In most cases, "port-forwarding" 2 addresses on the router will suffice. You want your router to forward NetMeeting calls on ports 522 and 1503 to the LAN address of your computer. (More information on IP addressing appears at the bottom of this document.)
At the Tampa Bay Computer Society, we have successfully configured different routers to work with NetMeeting. Here's a brief overview of the techniques used for several of them.
Browse to http://192.168.1.1
Default Login:
Go to: Advanced --> Forwarding
click on graphics above to see larger version
Note: On later LinkSys routers, Cisco changed the router interface. Port Forwarding is now accomplished from the Applications tab instead of the Advanced tab.
D-Link says, "Unlike most TCP/IP applications, NetMeeting uses DYNAMIC PORTS instead of STATIC PORTS. That means that each NetMeeting connection is somewhat different than the last. For instance, the HTTP web site application uses port 80. NetMeeting can use any of over 60,000 different ports.
All broadband routers using (only) standard NAT and all internet sharing programs like Microsoft ICS that use (only) standard NAT will NOT work with NetMeeting or other h.323 software packages.
The solution is to put the router in DMZ."
Browse to http://192.168.0.1
Default Login:
Go to: Advanced --> DMZ Button --> Enable --> Type in LAN address
FAQ: How do I use NetMeeting with my D-Link Router?
http://support.dlink.com/faq/view.asp?prod_id=1214
With the router powered on, press and hold the reset button for exactly 7 seconds, this will restore the router to factory default.
Note: By default the password on the router is left blank, and the default IP address is 192.168.2.1
Browse to http://192.168.0.1
Default Login:
Go to IE --> Tools --> Internet Options --> Connections --> LAN Settings
Uncheck "Use a proxy server..."
LAN / WAN Addressing
When your computer is behind a router, you actually have 2 addresses associated with it:
LAN Address: Your LAN address is assigned to your computer by YOUR router. It will most likely be 192.168.0.100 (although it's very possible that the last number can be 101 or some other variation). The 192.168 at the start indicates that you are dealing with a number originating at your end. One way to find out what address is currently assigned to you is to open NetMeeting and then go to Help followed by About. Your LAN address will appear near the bottom of the screen.
WAN Address: Your WAN address is your Internet address. Its numbers will vary widely. A visit to Your IP will display your WAN address. When giving out your address to a mentee so that they may contact you, this is the one that they will need.
Note: A feller named Robin Keir has written a wonderful little utility called IP2 that you may download for free, and it ferrets out and displays both your addresses. You will find it at:
http://keir.net/ip2.html
There you have it. This page should get you well on your way. You may address any questions or comments to me and I'll do my best to help get you up and running.
Doc (Dave Dockery)
President, Tampa Bay Computer Society