Some weeks ago my ISP did some infrastructure upgrades in the area and since then I'm seeing constant IGMP membership queries on WAN to the all-members multicast address (224.0.0.1). I understand this traffic to be link-local and likely is from the ISP's CMTS for all cable subscribers on the segment.
Should I be allowing these to pass, or is it better to keep dropping? AFAIK these shouldn't impact our services as we don't subscribe for IPTV.
IGMP-on-WAN.png
I have the same thing past week isp did network upgrades. I'm not familair with the igmp protocall. It is in the bogons list so i assumed it should always be blocked
Comcast?
Sorry I never updated this thread. I left it blocked and haven't had any problems with that. I think it will depend on what services you get from your ISP.
I experimented with IGMP locally because my switch supports snooping, but my network is so small that I didn't appreciate any difference.
Comcast and cox is not in my intermediate area. Used have dsl but that shifted to cell service and supposedly fiber in there . Spectrum mainly what it is here. I have noticed with certain rounters they seem to accept igmp from wan like the flint2 rounters. My network on the small size like yours and i dont have anything that requires that.
Just checked my settings and apparently I still have it enabled on my network :) In any case, the WAN doesn't participate in IGMP and unless something stops working (hasn't yet) that's how it'll stay.