Router connections showing on extender

Spike
Spike Member Posts: 4
Photogenic First Comment
I just started using Fing. Most everything runs on an extender due to the layout, so Fing shows it using the extender network. Oddly, at least to me, devices connected to the primary router, but not the extender, show in the device list. This includes a TV that is connected via internet to the router and the set top box, which also connects via internet to the router. I don't have a problem with this but I like to have a good understanding of what software is doing when I use it. Is there a good explanation for why I'm seeing those devices?

Answers

  • jjvoliver
    jjvoliver Member Posts: 16
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    If you're using your ISP provided modem/router as your main router, and Fing is also connected to it, everything in that network will show in Fing, regardless of if it's connected to the modem/router or a range extender.
    Now, if you have a separate router, and your Fing box is connected to it, instead of the modem/router provided by your ISP, then the devices plugged directly to the modem/router should not be showing in Fing at all.
  • Spike
    Spike Member Posts: 4
    Photogenic First Comment
    Thanks! I'm fine with that, but why does it happen? Where I live, most connections are fibre and it's difficult to find modems for it. (On the other hand, we don't pay rental fees for equipment.) So I do have an integrated modem/router from my provider, but from an academic point of view, I'd like to understand.
  • jjvoliver
    jjvoliver Member Posts: 16
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    OK, I'll try to make it as simple as I possibly can.
    If we look at this form a simple network stand point, we all have a modem provided by our ISP, which is our door to the outside.
    Some of these are just a gateway to the internet (which is not your case), and others (the vast majority and your case) also have router functions (regardless of if it's copper, fiber, satellite, coaxial cable, etc).
    In the first case, a router is not an option, but rather mandatory, otherwise you would have no way to provide your network devices with an IP address.
    In the second case, you have the option of just using that one gateway device to handle all your connected devices (assign IP addresses and any other function that the modem/router permits, and these are usually pretty limited).
    In your case, your modem/router provides all your network devices (including your FingBox and your range extender) with an IP form a pool of addresses of which 254 are usable (meaning that, in theory, you can have a total of 254 devices connected to that network). Our FingBoxes depend on these addresses and the MAC addresses of the devices connected to gather information about our network and the devices that conform it. 
    Now, in my case, which is only somewhat different than yours, even though my ISP provided gateway has the router function, I have that disabled, and added my own router to the network, which effectively turns the second case into the first case.
    As such, all the ISP provided services such as IP Phone and cable boxes will not show in my FingBox, but everything else will.
    The reason being that every single device in my home, including my FingBox, are in the IP address pool of my router, so the Fing Box sees it all, but the cable box is connected directly to my modem (which no longer performs router functions), just like my router, effectively separating it from all my personally owned devices.
    So, basically you network would look something like this (where your FingBox sees absolutely everything):

    While mine looks like this (where my FingBox does not see anything beyond the router):


    I hope this helps you understand a little bit better.
    As a matter of fact, if it wasn't for the fact that I don't like my ISP to have any more control over my network than absolutely necessary for my internet to work, I would even say that your setup is better for the Fing use, because you can tell what is happening with every single device in your house, even if the device is a TV Box.
  • Spike
    Spike Member Posts: 4
    Photogenic First Comment
    OK, thanks. I think my situation, though, is more like the second. I have a range extender that all my devices except the set top box and the TV run through. So in effect, I have a router in between. So I'm still a bit confused, but that's OK, I'm sure you're busy and thanks for the help.
  • jjvoliver
    jjvoliver Member Posts: 16
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    It's no bother. I get helped a lot, so it would be extremely ungrateful of me to not do the same if I can.
    Here's the thing, if you have your extender set as AP (access point) or Bridge, which is basically the same, you don't really have a router, because your modem/router is still the one assigning the IP addresses.
    If that is not the case, could you let me know what make and model are your modem and your range extender, please?
    That way I can see if there is something I may be missing (which is easily the case, hehe).
  • Spike
    Spike Member Posts: 4
    Photogenic First Comment
    It's not set as an AP. Also, I did not clone the router settings, I set it up with its own names for both frequencies. It's the TP-Link RE650. BTW, its network map doesn't show the clients that are not directly connected to it. Now I don't run DHCP on it, maybe that is why Fing sees the other devices that are not connected to the extender?
  • jjvoliver
    jjvoliver Member Posts: 16
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    That could very well be the issue. One device has to provide the IP addresses to the devices, if it's the modem/router, chances are the extender is set up as AP by default.
  • jjvoliver
    jjvoliver Member Posts: 16
    10 Comments First Anniversary 5 Likes Name Dropper
    OK, looking into it, the case with the range extender is that you cannot have the range extender assign IP addresses:

    Regardless of if you have it set up as AP (which basically makes it a wireless extension of your router all the same, only it would take the internet from the modem via wire and pass it on wireless), or Range Extender mode (in which case it's the same, only it takes the internet from your modem/router via WiFi, and leaves the LAN port open in case you want to plug something to it), the IP range and addresses is provided by your modem/router.
    So with this setup, your Fing Box will always see everything in the network.
    If you want to separate your devices from your Modem, you will need an actual router for that, which will give you the option of providing your devices in your house with a different IP range.
    SpikeTerri