Suriyakumarvijayanayagam c9be9b5807 "The cameras won't connect from my mobile internet" was answered by a timeout ...

Asked directly by the owner, about his own cameras, from his phone's
connection. The answer is physics and the product was not giving it.

A camera lives on the shop's LAN behind a router. 192.168.1.121 means
"something on the network I am attached to" and nothing more - from mobile
data, a hotel or head office it resolves to nobody, or to a completely
different device holding that number. There is no route in from the internet
and there must not be: an RTSP camera reachable from outside is how a shop's
cameras end up being watched by strangers.

That is why the product is split the way it is - the shop PC is the only
machine on the camera's LAN, and every other surface reaches it outbound,
which is what makes Watch live work from anywhere while nothing connects in.

What was wrong is the message. "cannot reach 192.168.1.121:554 - Operation
timed out" reads as a broken camera and sends somebody to re-type an address
and a password that were always correct. _wrong_network_hint names the cause
and separates two states that need opposite actions:

  on that network   -> check the camera is powered on and the address is right
  somewhere else    -> the COMPUTER is in the wrong place; no setting fixes it

- The local address comes from a connected UDP socket that sends nothing. It
  only fixes a route so the kernel will name the source address.
- The LAN ranges are spelled out, not is_private. That property also covers
  carrier-grade NAT and the documentation networks, and telling somebody who
  typed 203.0.113.9 that it is "on the shop's own network" is a confident
  wrong answer in the place people look first. Found by a test using that
  address as its example of a PUBLIC one.
- A DNS name gets no hint: nothing can be concluded about camera.local from
  the string, and guessing is the failure mode this message exists to fix.
- With no network at all it still names the cause and drops the comparison,
  rather than claiming to know which network this machine is on.

Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01KGcjxF1cNLcuwc3DAPcnfj

2026-09-30 18:00:44 +05:30

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