I did the following steps for accessing a http service that is hosted on my lan from outside the network.

  1. registered a hostname in no-ip.

  2. downloaded and installed duc

  3. did port forwarding setting on my router.(given the local ip of my machine and the port 80 with tcp as protocol)

  4. opened firewall for the port 80 which my http service is listening on. I am able to access the service from within my lan. When i tested port 80 with portchecktool i get connection timed out response

I suspect, that the port is blocked by my isp. But how to be sure about it? I even tried changing the port numbers of my service where it is listening and changed the firewall and port forwarding configurations respectively. but still there is no luck.

There was a setting for DMZ in my router, although I am not very sure about what it does, I provided the private ip of my host machine there. But still no luck.

Also, while trying to figure out the solution for this, I came across this link I dont want to pay any money to host my service. Can some one help me on how to fix this?

  • 1
    I suspect you are behind a enterprise grade NAT router... there is no way "around" it without getting a publicly routable static IP address from your ISP, which will likely cost an additional monthly fee of anywhere from $5-$50 USD per month. How to verify, contact your ISP. – acejavelin Jan 18 '18 at 19:20
  • What are the first two octets of the WAN address assigned by your ISP to the WAN interface of the router? – Ron Maupin Jan 18 '18 at 22:38

I suspect that the port is blocked by my ISP. But how to be sure about it?

As @acejavelin points out in the comments, the simplest way is to contact the ISP. They will typically give you the correct information regarding this kind of thing.

One issue (also pointed out by @acejavelin) is your ISP may have you behind carrier-grade NAT. If the WAN IP of the router is a private one (it starts with 10.x or 192.x), this is very likely the case.

Regardless of the situation, you may wish to try localtunnel (which requires Node.js). It has at least the potential of making the service available if it can't be done otherwise. A similar option is ngrok, though it has limits.

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