I'm getting totally hopeless setting up my router :(

Question

My dad and I are trying to get a A/V for about a month now without any success at all.
I have already previously sent a post on this forum and Ed have helped me a very, very long way. Thanks to him so much!!
The good thing is we could have a A/V together. Ed lives in Florida and I live in Switzerland.
So I have told my dad to set everything up the same as mine and it didn't work in-between us.
Ed tried to A/V with my dad and it worked fine. He then tried to do a 3 ways A/V and it worked very fine.
But when he quits the session to try to make a bridge between my dad and I, everything gets disconnected on both sides.
So we can both A/V with someone else but not in-between us. It is so wired because we have exactly the same settings, modem and camera.
I have controlled all that today with my dad computer aside mine.
Everything is set exactly the same way on both computers and both routers.
Of course when we try to A/V while on the same router through the same WAN it works.
By that i mean using the same router (either mine or his) through my airport express here at my home...
But as soon as he went back to his home and we tried to A/V it didn't work again. The message error "I" did not respond while I just did is on again.
I just don't understand anymore...I do not know what to do anymore. I'm totally hopeless
If someone understand a clue of our problem please feel free to tell me what to do.
Thank you so very much in advance
Seb
We both have:
Machine Name: PowerBook G4 17"
Machine Model: PowerBook5,7
CPU Type: PowerPC G4 (1.2)
Number Of CPUs: 1
CPU Speed: 1.67 GHz
L2 Cache (per CPU): 512 KB
Memory: 1 GB
Bus Speed: 167 MHz
Boot ROM Version: 4.9.1f1
Serial Number: W852807QSQ5
Sudden Motion Sensor:
State: Enabled
Built-in Ethernet:
IPv4: Configuration Method: DHCP
Running both Mac OSX version 10.4.2 Tiger
We both have an isight camera
Airport Express on both side
ISP is Bluewin ADSL (www.bluewin.ch)
Going through a router/modem called:
Netopia caiman 3346
On both side
The port forwarding is set on both side as below:
Service Name
*AIMTCP_1
Protocol
TCP
Global Port Range
5220 - 5220
Base Host Port
5220
Service Name
*AIMTCP_2
Protocol
TCP
Global Port Range
5222 - 5222
Base Host Port
5222
Service Name
*AIMTCP_3
Protocol
TCP
Global Port Range
5223 - 5223
Base Host Port
5223
Service Name
*AIM_1
Protocol
TCP
Global Port Range
5190 - 5190
Base Host Port
5190
Service Name
*AIM_2
Protocol
UDP
Global Port Range
5190 - 5190
Base Host Port
5190
Service Name
*AIM_3
Protocol
UDP
Global Port Range
5298 - 5298
Base Host Port
5298
Service Name
*AIM_4
Protocol
TCP
Global Port Range
5298 - 5298
Base Host Port
5298
Service Name
*ichat 1
Protocol
UDP
Global Port Range
5060 - 5060
Base Host Port
5060
Service Name
*ichat 2
Protocol
UDP
Global Port Range
16384 - 16403
Base Host Port
16384
Service Name
*ichat 3
Protocol
UDP
Global Port Range
5220 - 5220
Base Host Port
5220
Service Name
*ichat 4
Protocol
UDP
Global Port Range
5222 - 5222
Base Host Port
5222
Service Name
*Ichat 6
Protocol
UDP
Global Port Range
5353 - 5353
Base Host Port
5353
Service Name
*ichat 7
Protocol
UDP
Global Port Range
5678 - 5678
Base Host Port
5678
Service Name
*ichat 8
Protocol
UDP
Global Port Range
5297 - 5297
Base Host Port
5297
IP passthrough is disable on both side

Answer 1

Sebastien,
You may be well beyond this idea but I know that I had a similar situation. I could av chat with everyone except my wife at home. After configuring all the router stuff, it would still only work sometimes. Then I found out that every time our iMac at home would go to sleep or be turned off, it would be assigned a new IP by our router when it woke up or got turned on. This is especially true if you have other devices on your home network. As was just stated above, the ports you turn on are pointed at a specific IP address and if the address is changing all the time, you are no longer necessarily getting those ports open for the computer you are trying to use. You can check your IP address under system preferences>network. Since our router at home doesn't seem to be able to reserve a specific address for a device, I just don't allow the iMac to sleep anymore. If we do have to turn it off, I just reset everything with only the iMac plugged in and then it gets the right address assignment. Hope it works out for you. I have been successful in chatting with my wife first time every time for almost two weeks now after discovering the "sleep-IP address change" issue.
Richard