Cable WAN - can see all local node client IP's? Is direct connection possible?

[OpenSource Ghost]

If I place ISP (cable) gateway in bridged mode and use my personal router to run TCPDump on WAN port, then I can see 100's of "WHO IS" requests and replies for 100's of public IP's, all of which use my ISP's public IP range. Am I basically seeing all the replies/requests for local cable node? Is that node itself a bridged network???

If I have a friend who lives across the street and basically mirrors/copies my network (same ISP, same router model, same ISP gateway in bridged mode, connected to the same ISP cable node), then how can we establish a direct connection for file sharing and/or streaming sharing?

Note: ISP may be using CGNAT when ISP gateway is in router mode. When ISP gateway is in bridged mode, TraceRT does not show any hops within private IP range, but when ISP gateway is in router mode, TraceRT shows that first 3 hops are in private IP ranges.

 

[Nicklebon]

https://lmgtfy.app/?q=ARP

Seriously take an introduction to TCP/IP class.

 

[OpenSource Ghost]

I know what ARP request/reply means. I specifically asked whether ARP requests/replies I see are only for my ISP's local cable node (and not all of my ISP's network). My previous ISP also provided a gateway, which I also placed in brdged mode, and running the same TCPDump command on my personal router's WAN interface didn't show a ton of ARP requests/replies for a ton of IP addresses. It only showed mine and immediately assigned my router a public IP address. With my previous ISP, if I were to change WAN MAC address, I'd get a different public IP within a matter of seconds. Current ISP shows a ton of ARP replies/requests for a ton of IP's within my ISP's IP range and changing MAC addresses results in 30-60 minute wait before a new public IP is assigned.

 

[Nicklebon]

I know what ARP request/reply means. I specifically asked whether ARP requests/replies I see are only for my ISP's local cable node (and not all of my ISP's network).

You may know what it means but you clearly lack even a basic understanding of it. If you understood what ARP is, more to the point how it works, you'd know the answer to your question. Seriously, go take an introduction to tcp/ip class!

 

[OpenSource Ghost]

You may know what it means but you clearly lack even a basic understanding of it. If you understood what ARP is, more to the point how it works, you'd know the answer to your question. Seriously, go take an introduction to tcp/ip class!

Introductory, intermediate, and even advanced classes about basic polite human communication state to ignore the type of responses you provide. Basic knowledge about human psychology indicate you are not having a good day. I am sorry about that. I hope it gets better as it progresses.

I received a prompt response from ISP tech and I was correct in my assumption.

 

[D-EJ915]

Ignoring everything here and to answer your question, the way we work around this is to use nat.

Site A
normal ip range
192.168.1.0
translated range
10.10.10.0

Site B
normal ip range
192.168.1.0
translated range
10.10.11.0

Site B hits Site A's servers via the 10.10.10.0 network, etc. so they don't know the other one is 192.168.1.0.

 

[Ehren8879]

Not the node, but what's called the bundle interface on the cmts.

 

[SamirD]

So if your neighbor can put something directly on the network that has a share and so do you, in theory they should see each other and work unless there is some sort of filtering going on for various protocols. Otherwise, the easiest way to connect two networks is with an IPsec vpn tunnel.