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Ioannis
- 5th January 2008, 10:35
I am trying to connect a PIC controller with RS232-to-Ethernet adapter to the internet so I could read data from a remote PC.

The set up is as follows:

1. PIC with Serial com.
2. Serial to Ethernet adapter
3. Local Network with 8 port Switch and a DSL Router with 4 ports. My switch is connected to one port of the router.
4. Local PCs
5. Dynamic IP DSL Internet connection.

On the local ethernet everything is OK, naturally. I see all PC's and of course the PIC.
But I cannot acces the PIC over the Internet. I know that dynamic IP prevents this, but have tried with www.dyndns.com to create a virtual domain with no luck.

All I managed was to access my DSL modem from the remote PC which was the expected thing as I can understand.

How can I overcome the DSL router and see what is behind it on my local net?

Thanks,
Ioannis

paulwoody
- 5th January 2008, 14:55
Have you enabled Port Forwarding on your Router?

Angus Anderson
- 5th January 2008, 14:56
Hi Ioannis-

My ISP allows me to register a static sub-domain address, which gets around the problem of a dynamic IP address

Quote from my ISP (www.Axxess.co.za):

"No static IP address? No problem! vIP DNS will make your computer(s) accessible anytime, anywhere by associating a static sub domain to your dynamically changing IP address"

Suggest that u check with yr ISP to see whether they can do the same. Greece must be more with it than South Africa!

regards

Angus Anderson

rhino
- 5th January 2008, 17:41
Paulwoody is right. You need to set up port forwarding on your router so when a request comes in, it gets routed to the proper IP address on your LAN. I use dynDNS so I can see my parallax PINK module from anywhere on the net. Works great.

Ioannis
- 5th January 2008, 18:17
Thanks for the replys. I did not knew about port forwarding. Do all modem/routers have this option?

Mine is a DSL-584T D-Link type. I will search for this.

Thanks again.

Ioannis

Ioannis
- 5th January 2008, 18:32
OK. I think I got in part. Look at the attached gif. I don't know what to set at Gateway. Has this something to do with the Device itself?

Ioannis

rhino
- 5th January 2008, 18:33
I'm not sure if all have that option, but I would think Dlink would. I'm using a Dlink router. A quick look at the tech spec for this says" Packet filtering based on port, source IP address,
destination IP address, MAC address (ICMP/TCP/UDP)". Which sounds like it to me. On mine, you set up the port forwarding in the web page in the router for all of the settings.

rhino
- 5th January 2008, 18:41
I think the screen your in is for a Static Route. I take back what I said earlier.... I'm using a NetGear router. Here's what mine looks like.

Darrel Taylor
- 5th January 2008, 19:49
Althought this page was made for an internet file sharing program,
the part about port forwarding in the d-link should be the same.

http://portforward.com/english/routers/port_forwarding/Dlink/DSL-584T/Azureus.htm
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Ioannis
- 6th January 2008, 09:46
OK Darrel. That is what was needed! I will try and see how it goes.

Thanks to all.

Ioannis

Ioannis
- 7th January 2008, 10:22
Unfortunately I cannot connect to the local net. Is it possible that the Firewall on the DSL router prevent access from outside?

I cannot see anything else that might get in the way.

Note that I have installed and keep running the DynDNS Updater and have checked that the current IP is updated on DynDNS. Still, no one outside my local net cannot see that IP.

Ioannis

mister_e
- 7th January 2008, 14:33
Router are just pain in the.. to work with. Some brands are just more annoying than others. You might need to set few things in Windows as well. Nice start point is to have a sucessfull communication using VNC server or PC anywhere. Once you have it, better your chances are.

I'll suggest you to go on their websites (Symantec and RealVNC) and look at their FAQ.

rhino
- 7th January 2008, 15:13
One thing you can try as a test, and I say test because it is not a good idea to keep it this way, is to see if your router has a Demiliterized Zone setting. This will point at the IP address of the device on your lan and leave it wide open to the net. This way you can work your way backwards. I'm sure like Steve says, there are probably some other settings in your router that need to be set up. If I can do it, any trained chimp can.

Ioannis
- 7th January 2008, 17:11
At last! It works OK now.

I understood the problem from the beggining, only I did not know how to set the parameters.

Thanks to Paul for addressing exactly the point I was looking for to setup.

Steve: Yes, routers and modems are really myriads of parameters to set, nobody knows exactly what all this things do, and usually each device has different terminology from others making things even worse.

Rhino: I prefer not to do so even for a second!

Well, you may wonder what fix the problem? Time! Just time. I had to wait a couple of hours for DynDNS to make my settings active...

Ioannis

mister_e
- 7th January 2008, 20:43
hum, interesting, thanks for the update!

καλή τύχη!

Ioannis
- 7th January 2008, 21:16
Thanks Steve. It was really good luck on the matter, as I had a friend on the outside to have a look at the address I gave him. At first there was no response. After a couple of hours, my phone rang and, surprise, my friend told me that he had access to the link!

Pure luck the hole story!

Ioannis