What is a DMZ?

Introduction

Demilitarized Zone (DMZ) allows one IP Address (computer) to be exposed to the Internet. Some applications require multiple TCP/IP ports to be open. It is recommended that you set your computer with a static IP if you want to use DMZ. Linksys describes it as "...The DMZ Host setting allows one local user to be exposed to the Internet to use a special-purpose service such as Internet gaming or Video-conferencing".

I have found one router - the ZyXel 314 Prestige which has on board support for CUseeMe, Netmeeting, and other multimedia applications (games). The ZyXel router is the only router on the market that I know of that explicitly states support for CU-SeeMe.

Some of the information below has been provided by others and I have no guarantee that the CU-SeeMe functionally will be equal on all reflector versions.

What if your router doesn't have a DMZ?

NAT in your router can't be disabled? Bummer! So, do you throw it away and buy another one? Nope! You can add a second network card ($10 USD) and a small 4 port ($35 USD) hub! Make sure the hub doesn't have NAT (NAT can be masqueraded as 'marketing' names like 'Family Guard')!!! See details below.

From: CCrane"...I have 2 network adapters installed in my PC that I use for CU-SeeMe. One is plugged into a hub on the outside (external) of my Local Area Network and the other is plugged into a switch inside (internal) the Local Area Network. When I want to use CU-SeeMe, I disable the internal LAN card and enable the external LAN card. This allows others on the internal LAN to use the internet while I 'Dance Naked on the refs'."

This type of configuration would allow multiple PC's to be on the internet unencumbered by NAT, thereby allowing them to use CU-SeeMe. Remember to install software type firewalls on the PC's in the DMZ!

Linksys router settings

To setup the DMZ in the Linksys model BEFSR41 select the DMZ tab. This tab appears after clicking the Advanced tab.

To expose one computer, enter the computer’s IP address (the xxx part of 192.168.1.xxx goes in the box) and click the Apply button. Inactivate DMZ by entering a zero (0)....". Once this is done the PC's network interface card should be re-configured to allow routing thru BEFSR41. See Stoney's Net Meeting Page here for detail with pictures on how to finish the Linksys configuration.

From chat on a reflector

ASCIIrider: Hoople, I set my PC's NIC IP to the internet IP I was connected
to.... only problem is.. with a dynamic IP, if the router reconnects, I have
to change it.

SMC Barricade Broadband Router

NOTE: step 1 is the WAN IP of the router.

I have Cable Modem & SMC Barricade Broadband Router and I have got cornell cuseeme v1.0a to work on Windows XP with very little knowledge and lots of trial and error here's how i did it ....

1. From the router's system status page I made a note of my WAN IP Address, Subnet mask and the two DNS servers addresses.
2. In a DOS box run ipconfig & I made a note of my local IP address, subnet mask & default gateway.
3. Go to your network properties -> TCP/IP -> properties.
4. Select "Use the Following IP address" and enter your IP & subnet obtained in step 1.
5. Enter the default gateway obtained in step 2.
6. Enter the the two DNS server address obtained in step 1.
7. Select advanced and Add IP address.
8. Enter your IP & subnet mask from step 2.

OK to everything and that was it Cornell CU-SeeMe working under Windows XP with a router & nat. I found the only reflectors i had problems connecting to were WP2.1 (Apart from CUseeme World 13 & 14 which both worked ok), White Pine 3.5.07 & Cornell.

Again I hope all this make sense and is of help.

cheers

scott

NOTE: Only White Pine 4.0.2 (and above) MPCS reflectors (CUseeme World 13 & 14) worked for him ---- the other 98% of the reflectors DIDN'T!!!!

Comments? Send them to Hoople <hoople_ny@hotmail.com>