This is just my experience, YMMV as they say…

In April of 2022 my VOIP home phone stopped receiving incoming calls. I could still dial out, but nobody could call the house. I received warning emails from Skyetel every 3 hours that my SIP endpoint was unreachable by their servers.

Since nothing had changed on my end, I suspected that something changed with my provider: Comcast/xfinity. Similar to my experience with British Airways, I found that xfinity has now automated everything.

I understand that automation helps if someone just needs to reboot their router, or forgot their wifi password. But for those who need genuine help getting shit done, it presents a huge barrier. It took me 9 calls and 3 trips to the xfinity store to get this resolved…

Approach 1 (trying to fix the problem directly)

I phoned tech support to explain that port 5060 (for SIP service) was being blocked on my connection.

The first guy I talked to said they won’t open up that port unless I subscribe to xfinity’s VOIP service. Honestly, I didn’t want to talk to this guy anymore. He was obviously from India. No offense, but he sounded more like a scammer than a helper. I wanted to talk to someone who actually works for xfinity in the US, that actually knows how their network is set up. Before I hung up I got the phone number for Advanced Technical Support. It’s 888-780-8571. You’re welcome.

I called that number and magically wound up speaking with an actual technical rep based in these United States. BTW, this won’t happen every time – I’ve yet to figure out what automation magic I did to skip past the overseas nonsense.

When I mentioned my issue he referenced this page https://www.xfinity.com/support/articles/list-of-blocked-ports which I had also been looking at, noting that port 5060 isn’t in the list. He said I might need to do some configuration in my modem’s settings to forward that port.

But the Netgear CM1000 isn’t a combo modem/router. It doesn’t have a firewall or port forwards or anything. It just passes all connections on to my OpenWRT router which has firewall/forwarding/wifi/etc.

So the tech guy suggested I try an xfinity-supplied cable modem (at a rental fee of $15/mo) to see if that solves the problem. I wasn’t thrilled with the extra cost, but he said it’s pro-rated and might be worth seeing if it fixes the problem.

Approach 2 (playing the game)

So I went into my nearest xfinity store, went home with a new cable modem, and set it up. Then, to my dismay, when I went into the port forwarding settings on the modem, I consistently got this error:

I called technical support back and they said:

You need to go back to the xfinity store and get a different modem that is supported by the xfinity app. I’ve made a note on your account so they’ll give you the correct one this time.

WTF. OK, so I went back and returned my modem for another one. The new one worked with the app. I did have to do some weird things like disable IPv6 on my router so that it would show up in the xfinity app as an available device and port-forward destination because xfinity only supports port forwards via IPv4.

What’s really going on?

After configuring the router and updating my IP at Skyetel, it seemed to work πŸ’ͺ Our home phone now rings after dialing. I called xfinity tech support again to re-activate my Netgear CM1000 to see if it will continue to work. Hey – it worked… But why?

My hunch is that by selecting a port forward in the app, something else is getting configured in their network to allow incoming connections – something upstream from your rental router. We’ll see how long the setting lasts before I have to go (temporarily) rent one again 🀞 Also – I was able to reactivate IPv6 in my router without issue.

The next day, the phone rang and it was music to my ears! ☎️ It was my daughter’s friend and they made plans to get together. Then the day after that, I received my first spam call 😱

Leave a Reply