Opening a Port through a Router

Hi,
I have a D-Link 624 Router connected to a DSL Modem. I run a Dell E521 Desktop (w/ Win XP (can't run Linux on it for graphics reasons)) and Toshiba Satellite L305D Laptop (w/ Win Vista, * Mint Linux (primary), and Puppy Studio) connected. I set the Router to allow 'Home Network' access for the Laptop to the Desktop files, but for various purposes we aren't allowing internet access to the Laptop.

I'm not very familiar with porting through a router, but I do understand that Ports can be opened through a Router for different purposes. I would like to allow access for Last.fm (or Pandora Radio) to the Laptop but don't know what steps to take, or if it is even possible under these circumstances.

I looked through some of the Forum Threads but didn't find any directly related to this issue. I would like to learn more about working with Ports. But if you can point me in the correct direction for guidance in the matter stated above, or have suggestions/answers, I would greatly appreciate it.

If you prefer, you can contact me directly at the follow email:<snip>


Thanks in advance.
JC

 

hi - generally setups like this allow all outbound ports by default and thus i think that the issue is probably not to do with a firewall blocking ports. Can you give details of the 2 networks you are running (i.e. the one that is on the LAN side of the Dlink and the network between the WAN side of the DLink and the ADSL Modem). It also could be down to how the ADSL Modem is NATing the traffic (how a Modem has one internet facing IP and multiple internal IPs on the LAN).

Post some more detail and i will help you out
Cheers

 

Hi and thanks for the response,

I have a Basic DSL package from AT&T (@700Mhz) from their modem into the D-Link router. The Desktop is connected directly through an ethernet cable to the router. I do have a separate ethernet cable for use on the Laptop, although I don't make it available at this time. The Wireless is set to allow connections to other machines (if there would ever be such) except this particular Laptop which we prefer to restrict internet access on.

I saw somewhere that a Static IP from your ISP is needed for Port Forwarding, without which it cannot be done. I currently have a Dynamic IP address. Going into the setup of the Router I am able to turn on/off the internet access, but the Port settings don't seem to do any thing. When I open the connection, then set the port on the Router and Last.fm connections it continues to work after I close the internet connection until the songs change. Other than the "ipconfig" command to read settings from the router/modem I'm not sure how to check whether the Port I assign is actually effective or not.

I'm not sure how much more information you need. I can get that if need be. Hope this isn't just a lot of bother. Thanks again,

JayC

 

Is there a model number on their modem (sorry for the delay in responding - thought i would get an email when a response was posted)

 

The Modem is a Westell ADSL2+ (Style MSTATEA). No other information except access codes.

I tried using Filter to allow a single port and various Port settings when blocking the internet, leaving the assigned port available. This didn't seem to work (not really sure what I'm doing, just going by what I've read on forums).

 

ok - so there should be 2 networks here - the network that the ADSL Modem Runs (the transit network) and the second that your D Link Runs (your internal LAN). They can't have the same subnet on both networks.

So with your D Link unplugged from the ADSL Modem plug your laptop in to it into a LAN interface on the Modem. from the command prompt do an ipconfig/all note the IP Address and Default Gateway.

If the IP is within the range of 192.168.0.1 to 192.168.0.254 then you will need to configure the LAN on the D Link with a range of something else (i.e. 192.168.1.x for instance - but i will come to that later)

Now check you can get on to the internet - if all ok then we need to configure the D Link.

If you start by doing a reset of the D Link and then plug your laptop into a LAN interface of the D Link and nothing else accept the power.

Then go to http://192.168.0.1 from you browser and use admin as the username and i think the default password is blank.

If the modem did have the IP in the range of 192.168.0.x then you will need to go into the LAN config on the D Link and configure the IP as 192.168.1.1 and the subnet as 255.255.255.0 - then check the DHCP is within the range 192.168.1.x to 192.168.1.y. At this point the D Link may kick you out - if that is the case then open a command prompt and do and Ipconfig/release followed by an ipconfig/renew once done you should have an IP in the range 192.168.1.x and now go to http://192.168.1.1 to log in to the D Link.

Then configure the WAN as Dynamic - this will mean that when you plug your WAN interface from you DLink into the LAN on the ADSL modem it will get an IP address from the DHCP server in the Modem (like your laptop did in the first test)

To check this click on the status tab along the top of the D Link menu and under WAN you should see that the WAN interface is shown with an address of 192.168.2.X (where X is a number from the DHCP range.)

Then you should beable to configure your wireless and all should be able to connect out to the internet at the same time....

Let me know how you get on

 

I really appreciate your help in this. I'll check this out and get back.

Thanks

 

My Modem's IP was preset to 192.168.1.x. The Router's IP was preset to 192.168.0.x. On setup, I was directed to 'bridged' the Router to the Modem. The WAN is set to Dynamic PPPoE. Any machine connected directly or wirelessly has an IP within the range of 192.168.0.100 - 192.168.0.199

If I understand you post correctly, you're suggesting connecting the two without bridging, is that right?

Getting Internet access on either machine isn't a problem. But I do not want internet on one particular Laptop. However, I would like a couple of ports open for certain applications. Under current condition I cannot access anything through any port on the IP that is 'blocked'. While an IP is blocked, is it possible to get access through a port?

I may well be asking for something I simply can't do. Thanks again for your assistance.

J