can neighbor tap my internet with splitter or something?

LinuxNub1

Junior Member
Dec 16, 2020
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is my cable modem tapped? usg ip takes me to my casa router

can a neighbor above me in condo tap my internet line which is called coaxcable i figure?? long story so wont explain why i think he would do such a thing! anyways can he tap our coax line? I called our ISP and they said that's impossible.. is it really? our place i'd say was built in 90's so it is very old place!

I call bs.. our ISP and by far the worse ISP I EVER dealt with in my entire life. i've had many diff internet providers. They do not ever answer phone calls even months before covid. Always have to leave a voicemail and wait a day or hours for a reply, and it's bad support. so now that's explained I'll talk about my ISP etc and usg setup

Normally when resetting modem and connecting it to a different computer instead directly into a router it changes ip as i recall! ! in my house you get a new " outside IP Address" I've reset modem let it sit for a while then directly connected modem to the pc and ip didn't change. I repeated it again but then with another computer.. IP didn't change... it did in the past, and also when I HAD COX Communications this always worked. I'm talking about my real outside ip not local lan ip. :p im a n00b but still know a bit

so my USG uses DHCP to work so that means we don't have a static ip correct? So I assume the real outside WAN IP should have changed. hasn't in over 8 months and around the time person moved in. I know even dhcp ip's can stick for months and months but normally it should change still. I'm aware every ISP operates differently though and I'm trying to keep that in mind.

I'm going to display the USG router setup below. BTW I called my ISP explained what I said above, and he said I'm probably not setting router up correctly, and that a neighbor above tapping coax cable through wall and or box is impossible.. i even said he cant use splitter etc? he said no!

I CALL BS. He said it doesn't sound correct my setup yet denies tapping is possible! So I'm puzzled. If my ISP literally came out and looked at the box could they tell if someone tapped it? even if they check outside and inside my room with coax wire coming through my wall? Since I know they can't just barge into upstairs neighbors room!

my USG router IP which I checked is in fact a IP addressed to my isp though but takes me to another router login only for local access which is a login for "my casa" , so maybe I'm just paranoid because of past incidents of being hacked in past at other place which was from someone hacking my pc via virus totally different situation

Im using a surfboard arris modem btw! I'd appreciate any advice plz!

USG pro


my casa login when I type 104. ip in top right into browser... i looked them up ip for my casa is affiliated with my isp just find it really odd. normal to be insecure? i know the unifi usg router has no ssl etc so if its legit i could see why its saying insecure also!


surfboard modem!


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SamirD

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Jun 12, 2019
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So a couple of things--is the IP your usg getting a public external IP? If so, you're completely safe from any internal hacking attempts.

If not, you're still safe as they would have to bypass your usg just like a hacker from the outside would.

I've lived in a complex where they had a site router that did an internal IP address assignment of public IPs and if you scanned the public IPs you could find other residents' routers (and in some place even computers!), but that would still be no different than scanning a public IP space, so from a security standpoint it was essentially the same.
 

VirtualLarry

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Aug 25, 2001
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I guess, in my mind, there's various degrees of "tapped" on you line.
1) Your local LAN, behind your router and on-site cablemodem. If this were true, they could directly scan and access your local IPs.
2) Someone connecting a second cable modem to your COAX line. This would not allow access to any of your data, or IPs behind your router and cable modem. To them, that's just "out there on the internet". In fact, most cable ISPs effectively function like that, and often, sometimes, depending on how they wire up various apts. and townhouses, COAX connections / cable outlets may be daisy-chained, or run from a common splitter that connects upstream to a cable plant.

I'm not quite sure what "my casa" is, in your case, or why a cable ISP would have some sort of apt-local head-end server or whatnot that the local CPE would connect to. I've seen/heard of Verizon FIOS using a whole-apt. ONT, and then using VDSL "modems", to uplink to the shared fiber ONT, but I haven't really heard much of cable companies doing something similar, although they could.

I guess, as far as the IP not changing goes, possibly your apt. complex does have some sort of remote-terminal / local head-end, and it has a "pool" of public IPs available to your apt. complex. Before your neighbor moved in, perhaps there were several free IP addresses, and when you shut off your cable modem and router, and power them back on, you would get randomly assigned one from the pool, but now that there are more neighbors claiming IPs, there's only one left for you.

Now, that said, I do have some vague knowledge, that it may be possible for someone to use a cablemodem to "fake" a head-end, and somehow gain access to the certificate stored in your CPE (cablemodem), and then "clone" that certificate, so they look like "your" cablemodem. Kind of like cloning a cell-phone SIM. This would, likely, allow internet access for your neighbor, on your plan, but I don't think that both cablemodems could operate simultaneously on the same line, at the same time, with the same cert. Maybe someone who is "deep" into cable modem tech., could tell us more.
 
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LinuxNub1

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Dec 16, 2020
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So a couple of things--is the IP your usg getting a public external IP? If so, you're completely safe from any internal hacking attempts.

If not, you're still safe as they would have to bypass your usg just like a hacker from the outside would.

I've lived in a complex where they had a site router that did an internal IP address assignment of public IPs and if you scanned the public IPs you could find other residents' routers (and in some place even computers!), but that would still be no different than scanning a public IP space, so from a security standpoint it was essentially the same.
yes. ip address works only if connected on my internet / wifi.. off the wan / wlan etc like using my iphones LTE it wont load. the ip wont. nothing happens. but on it the IP works... the one top right in USG picture where i say my casa. its for sure some mycasa network broadcaster ? i checked IP and is owned by my ISP! If so my usg should protect? I find it odd i am even able to access mycasa page for the box outside. How secure is it you would think ?
 

LinuxNub1

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Dec 16, 2020
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im concerned because i google the IP for mycasa that is my router ip and it is owned by my ISP! But only from my LAN not outside it! so i shouldn't worry? So even if someone tapped my coax line with a splitter above me in their condo.. they still cant get my data? plz let me know if im uinderstanding .. if so i guess i dont have to wory anymore.

Im using the unifi USG pro 4 firewall router
 

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heymrdj

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Depends on the ISP whether or not you get a new WAN IP just because you change devices. I have Comcast Business without a static IP, yet my WAN IP has never changed since I got the service years ago, even after changing out the device connected to the modem (TrendNET firewall, to Asus, to Netgate SG3100) several times.

From my understanding, no modern COAX system can simply be tapped because it’s two way communication. The headend expects a specific device that is whitelisted for the account. If I take a brand new Arris Surfboard modem and connect it to COAX anywhere in my house, or even where the current one is, it doesn’t connect to Comcast’s network. I have to call Comcast and give them the hardware ID of the new so they can activate it in their system, then a few minutes later the modem will come online. Meanwhile, the old modem will no longer work. When I was a traveling technician, I replaced probably a few hundred cable modems over the years, especially after the initial Comcast Gateways (with internal AP’s) had issues with stability. That and the previous generation Netgear Comcast modems that got a firmware upgrade pushed down from Comcast that hated Fortinet firewalls to be bridged to them.
 
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mxnerd

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router's public IP of course is owned by your ISP, nothing new.

Every ISP has different DHCP lease time, no set rules. Spectrum's DHCP lease time is 2.5 days.

According to this article, typical DHCP lease (MAC and IP address association) time is 7 days in the USA.


And if the cable signal is split before your cable modem's WAN port, you neighbor has no way to tap your data.
 
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LinuxNub1

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Dec 16, 2020
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my router ip is public but only accessible via lan/wan if on my local network but yet shows as owned by my ISP. so this is perfectly normal? It's different then my actual public IP that shows up when i google "whats my ip" correct thats ok? that one also shows as owned by my isp? THats main reason i got concerned something was up! If so I shouldn't be worried correct? just trying to make sure I'm understanding 100%

Check attached image :) thx thats my usg firewall router
 

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mxnerd

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My Casa is the cable modem right? And (UniFi? )USG Pro is the router/firewall correct?

If both yes, of course they have different MAC address. Every single ethernet device needs to have a different MAC address to communicate. The first 3 hex digits are vendor number and next 3 hex digits are serial number.

If the number are the same, there is no way to distinguish the two even if they are totally different devices.

When you type in the public IP address into the browser, the traffic goes out from your LAN and then comes back in from WAN. It's not someone else log into you LAN and tap your data.
 
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LinuxNub1

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Dec 16, 2020
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My Casa is the cable modem right? And (UniFi? )USG Pro is the router/firewall correct?

If both yes, of course they have different MAC address. Every single ethernet device needs to have a different MAC address to communicate. The first 3 hex digits are vendor number and next 3 hex digits are serial number.
I have a modem and the usg is router. but the ip top right i say is mycasa is also a login. / router/ i find that odd. isnt it just supposed to be 1 router ip per home?.. my setup i show above is inside my router aka USG firewall panel and displays my casa which isnt my modem. not same mac. it says its owned by my ISP yet my public accessible real ip left side in pic is my ip forums like here would see but mycasa router isnt. but then i also have my routers own ip 192.168.1.1 my modem mac address at all and isnt anywhere showing in my usg router i put in pic above! its some other mac address i've never seen. which that mac im unaware of is the mycasa one
 
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mxnerd

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Please tell me your modem brand/model. And exactly what My Casa is? Is it your ISP? It also provides the modem or what?

My Casa could be a modem / router combo, which nowadays is called gateway.

So if you are behind a gateway, then yes, you have 2 routers and you are cascading them in a configuration called double NAT. And you are able to access both router's login page. Whether you can login depends on whether your ISP allow you to login. Many ISP provider will lock modem/router or gateway's login page.
 
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LinuxNub1

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Dec 16, 2020
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Please tell me your modem brand/model. And exactly what My Casa is? Is it your ISP? It also provides the modem or what?

My Casa could be a modem / router combo, which nowadays is called gateway.

So if you are behind a gateway, then yes, you have 2 routers and you are cascading them in a configuration called double NAT.
so my modem is a arris surfboard. i then own the unifi usg pro 4 for my router / firewall... which modem connects into that! but the my casa router ip shown above? idk? its only accessible locally and is owned by my ISP when i googled it. It is not accessible outside my wlan / lan network. thats why im conerned my line is tapped! dunno why usg shows a router ip when it is a router and shoots me to some my casa login. i tried ip on several devices it works. only locally. but i thought only my usg is a router?
 

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mxnerd

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You still didn't answer WHO is your ISP? And you kept mentioning my casa router, what is that?

A login page does not necessarily be a router login page, it could be a web site login page.
 

LinuxNub1

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Dec 16, 2020
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You still didn't answer WHO is your ISP? And you kept mentioning my casa router, what is that?

A login page does not necessarily be a router login page, it could be a web site login page.
ISP = west coast internet. my-casa never heard of it. but apparently it can help ISP's expand for cheap i believe? . just dunno if i need to worry. my isp isnt my casa at all! thats why im confused why a mycasa shows up for router ip while im in my USG router firewall.. which is 192.168.1.1 under lan in pic . it says the local router ip is infact west coast owned internet ip when googled but only accessible locally. and my outside ip top left under dhcp part is what forum admins see when i post here which also is west coast internet owned

my modem local login address is = http://192.168.100.1/ which is a ariss surfboard

 

mxnerd

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I probably know better now. That 104.xxx.xxx.xxx IP probably is owned by casa-systems which is part of west coast internet or CO-OP with them. And that IP is not accessible by any one except casa-systems.

Your LAN ----- WAN port ----- CASA-Systems ---- West Coast Internet ---- Internet

So, that router means its just a route (router) owned by CASA Systems, nothing to worry about!

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LinuxNub1

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THANK U! OK! got it.. sorry for the pain! LOL i myself having trouble understanding so i had trouble explaining . thank u mxnerd :) seriously appreciate it, and everyone else that has posted before you!

totally makes sense now! im figuring they co -op with my casa to improve there performance. i'd call them everyday for months lmao! complaining because internet always disconnected! it was really bad. SO i think they started using 5 g casa product or something to help expand and improve the internet with doing it in a cheap way. i remmber isp tech saying there being cheap and fixing things in a bandaid way instead of upgrading the entire network system.. so its cheap for them to fix problems. so this is gotta be the "Cheaper method" to solving slow / sloppy connections
few months back as i said speeds / connection was trash, and now is amazing. pay for 100mbps get 200! just glad my internet is good now just got concerned seeing that lol! feel relief like crazy.. you don't even know! Guessing their using one of those for access points between others maybe using 5g ? into each box or something View attachment 35786
 
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SamirD

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my router ip is public but only accessible via lan/wan if on my local network but yet shows as owned by my ISP. so this is perfectly normal? It's different then my actual public IP that shows up when i google "whats my ip" correct thats ok? that one also shows as owned by my isp? THats main reason i got concerned something was up! If so I shouldn't be worried correct? just trying to make sure I'm understanding 100%

Check attached image :) thx thats my usg firewall router
So then your IP is NOT a public IP even though it is a publicly routable IP. Kinda stupid since they are essentially paying for IP addresses that they can just get for free via the 192. 172, and 10.10, etc private subnets.

So essentially it is like you have a private IP, not public and that router you're hitting is probably the one handing out the IPs.
 

MtnMan

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So then your IP is NOT a public IP even though it is a publicly routable IP. Kinda stupid since they are essentially paying for IP addresses that they can just get for free via the 192. 172, and 10.10, etc private subnets.

So essentially it is like you have a private IP, not public and that router you're hitting is probably the one handing out the IPs.
I helped a clueless friend with his network a while back. He needed some help with securing his wifi after the geek squad completely confused him. He had DSL from the looking at the config on his router I noticed that the WAN address on his router was a 192.168.77.x or similiar. They were conserving their public IP's by putting him behind their own NAT router.