Public IP static at modem but dynamic at router?!

[antekit2000]

So a few days ago I came up with the idea of hosting my own web server for my files. I've installed everything on my computer, but, while looking for my IP address, I noticed something strange: all the sites for checking IP had different answers. After some testing, I noticed that when I connect my PC directly to my (Motorola SB501) modem, there is only one IP told by all the sites, but when connecting to my (Tenda 11N) wifi router, the issue persists. Therefore, I believe this is not an issue with DHCP/Static IP, as the IP is static when connected to the modem, but I believe there is something with the router or its configs. And by the way, resetting the router to factory settings did not help!

 

[kanewolf]

Unless you are paying your ISP for a static IP, don't assume your public IP address won't change. You need to use a dynamic DNS service to associate your public IP address with a URL that won't change. Then forwarding port 80 (or 8080 or some other port) from your Tenda to your PC should be all that is required. You REALLY shouldn't worry about the IP number, because you probably aren't guaranteed a static IP. Use DDNS service to manage it.

 

[antekit2000]

Unless you are paying your ISP for a static IP, don't assume your public IP address won't change. You need to use a dynamic DNS service to associate your public IP address with a URL that won't change. Then forwarding port 80 (or 8080 or some other port) from your Tenda to your PC should be all that is required. You REALLY shouldn't worry about the IP number, because you probably aren't guaranteed a static IP. Use DDNS service to manage it.

I know I'm not 100% guaranteed a static IP, and I do use a DDNS service. But I don't think it's normal to have different IPs at: google, whatismyip.com, iplocation.net etc (the last 3 digits are always different). And again, this doesn't happen when connecting directly to the modem, meaning the ISP is not a problem...

And btw, the router is mine, it wasn't given to me by the ISP.

 

[kanewolf]

What does your DDNS resolve to? That is the only thing that matters.

 

[failboat]

So a few days ago I came up with the idea of hosting my own web server for my files. I've installed everything on my computer, but, while looking for my IP address, I noticed something strange: all the sites for checking IP had different answers. After some testing, I noticed that when I connect my PC directly to my (Motorola SB501) modem, there is only one IP told by all the sites, but when connecting to my (Tenda 11N) wifi router, the issue persists. Therefore, I believe this is not an issue with DHCP/Static IP, as the IP is static when connected to the modem, but I believe there is something with the router or its configs. And by the way, resetting the router to factory settings did not help!

A Dynamic IP changes, but usually not often. It's fully in the ISPs hands.

The reason you are seeing one IP is due to how NAT works. Which will be important to understand since you will need to use portforwarding.

https://computer.howstuffworks.com/nat.htm