Modem constantly sending to Port 1900: SSDP discovery of UPnP

Networking & Firewalls
1

Modem_SSDP
Modem_SSDP1441×119 31.9 KB

My modem seems to be constantly broadcasting SSDP discovery to port 1900.

My questions are:
Why?
Why does it only seem to be on one of my subnets?..or at least only triggers default deny rule on one subnet.

Thanks
Sterling

2

You’re needing to track this down even further. I’ve heard Microsoft Windows has a service called services.msc that does this.

I’ll leave this here as well.

The good news is that it’s already being blocked.

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3

You may want to review the below. UPnP uses it for instance, and some routers are known to have a bad UPnP configuration (maybe your modem is among them?)

4

@Moseph_V @xMAXIMUSx
Well, that was interesting.
That silly 192.168.0.1 …only looked like my modem…it was not my modem’s IPV4 address.
Some devices are doing network discovery inside my network.
No Windows devices that I know of. Some IOT stuff and phones.
Anyway it kind of bothered me so I rolled my own Bogon network rule and called it a day.
As @xMAXIMUSx said “The good news is that it’s already being blocked.”
Thanks for the responses ! ! !

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