Port Forwarding/Firewall Query

[silas2]

I've got the BT 2Wire.com gateway router, and I'm mystified by the setup screen, when I want to add more than one firewall pinhole for a pc on my network, it complains that that pinhole is already assigned to another pc. But I don't understand that a pinhole in the firewall isn't the same as 'port-forwarding' is it? I might have multiple pcs behind the router all of which need the same hole in the firewall.

[markp]

Hi silas2,

When you open a port/pinhole, you can only only the 1port at a time, for example, if yo opned port 80  for web, the router opens this agains the IP the router receives from BT, and this port can only be assigned to 1 computer, otherwise the router would not know who to forward the request too.

If you need to open the same port number for more than one computer, you would need to have a range of public IP's as you would bee open the same port for each IP, so if you had the IP range 12.13.14.15 to 12.13.14.19, you would be able to open the same port for .15, .16, .17,.18 and the .19 IP the the range.

the other way would be to change which port on each device/computer to that instead of it being port 80 on each device, you use 80 on one, then 90 on another.

Regards

Markp

BT Business Forum Moderator

[silas2]

I'm still confused over the difference between port-forwarding and a firewall. I understand that if I had a public service like a mail-server behind the router, I would have to port-forward traffic for that to a single pc, but if, for example I wanted to allow Voip on 2 pc's behind the router, I would want them both to have the firewall allow communication on port 5060, for both computers, surely?

What am I misunderstanding?