Port forwarding in a 3G connection

RouterOS Beginner Basics
1

Hi,

I have replaced wan connection in 751G into a 3G modem connection through ppp client. All works fine except the port forwarding. I cannot access the services like webfig remotely anymore. I tried two different sim card operators. Do I have to take something else into consideration in the configuration to make it work? Thanks.

2

3G operators give a static IP everytime but they give it to multiple clients hence I guess they drop port forwarding for those IP’s. Ask your 3G provider for a seperate static IP for your connection.
You can use Dydns like services instead.

3

Hi,

even if I use dyndns it doesn’t help, because I am not able to access the router through 78.30.122.10:80 from outside the network at all. Maybe the operator blocks all ports, unfortunately I don’t have any other USB soho router to test it with.

In the PPP configuration I have ‘Add Default Route’ enabled. I am wondering if this gives you a clue to set up the port forwarding correctly:

 #      DST-ADDRESS        PREF-SRC        GATEWAY            DISTANCE
 0 ADS  0.0.0.0/0                          10.112.112.141            1
 1 ADC  10.112.112.141/32  78.30.122.10    ppp-out1                  0
 2 ADC  192.168.1.0/24     192.168.1.1     bridge-local              0

Can anyone tell me how the forwarding should look like based on the above route? Thanks.

4

Many mobile networks block inbound traffic other than that for connections initiated by the mobile device - at least on their common APNs. They will usually have alternate APNs which allocate public IPs and do not block inbound traffic.

5

Based on what was said I assume that I will not be able to do port forwarding successfully unless I get a different APN from the network operator. Does this apply to IPsec connections also?

6

Who is your 3G provider and what package do you have?

Many 3G providers NAT their network so even though it may appear as though you have a public IP address, it may have been NAT’d and so not actually visible from the internet.

7

I decided to set up a 3G backup link - for the tests I used the cheapest packages available on the market and no business packages at all. This is probably why I didn’t get the expected results with port forwarding. The providers are Play and Aero2 from PL to name a few.

8

If the inbound traffic is blocked you could have the router VPN to you at a central location and enable management over the VPN interface.

9

I don’t have any experience with VPN yet, but when I’ll get there I will come back to the forum :slight_smile:. Thanks for all your advice.