Xfinity DNS and Roon

1. DNS is not likely to be your problem but you SHOULD use OpenDNS.  Intermittent streaming is more of a network quality issue.

2. Your Roon device can have it’s DNS set locally, for instance every Mac/PC/Tablet lets you set the DNS service in the network settings, regardless of upstream components. This will override the router.

3. For security reasons I don’t use the cable provider’s router. In some cases they may give you a modem for free, and turn off the Wifi features. That’s fine. You buy your own Wifi router and wire it downstream from Xfinity or whoever, then you have 100% control AND can turn off remote access, which is a key security feature. They may break into my cable provider’s router but they won’t get any further.

I am not aware of an aftermarket router that will work with the non-standard fiber optic cable that Xfinity uses for my area.  
 

That is the issue with fiber - it is specific to the company.

Let me teach you all something then!

The first point I’m not 100% sure of... the rest I am. :)

I believe that since there’s a federal law saying cable companies can’t force you to rent their modems cable providers will stop billing you if you ask them to turn off Wifi. This happens in my situation. The issue is they don’t have separate modem/routers. They buy in bulk combined modem/wifi routers so even if they have a specific fiber modem, they can’t force you to pay for it. The’ll just remotely disable wifi. On the other hand, even if this is wrong you just want to disable Wifi entirely, including any public Xfinity access SIDs, they just pollute the channels.

OK, the rest of this I’m 100% sure of.

You can chain one router after another, essentially turning the first one into a modem. The trick there is to keep track of the subnets. Notice the IP address range your home devices have before making changes, it will be something like:

192.168.x.y

You want to keep track of everything up to X because when you attach your new router you want a different X at least. Your new router will use DHCP to get an "external" address from your router (it’s more like front porch address), and then assign internal IP addresses based on your new range.

So if your cable modem is offering : 192.168.1.y

Change your new router to offer: 192.168.10.y or 192.168.2.y either is fine. OF course the router MAY offer an entirely different private IP address, like: 10.1.1.y

in which case using 192.168.1.y internally is fine. They just have to be different in one of the first 3 numbers. 192.168.x.y is a non-routable, private address range. 

Now you have a situation where all your devices connect to your internal router, and rely on it’s settings for DHCP which includes IP address AND DNS servers.  This means that you have 100% control over the internal address ranges, wifi settings AND external DNS services used.

So, the security precautions are:

1. Disable Wifi on original router

2. Disable external access on new router

This will prevent anyone from outside your home from reaching in, and that includes your cable provider.

With this method you can now go to Amazon or wherever and buy any Wifi router you choose. .

PS:  192.168.x.y is the most common private IP range and you should stick to it unless you have a very good reason not to and pretty much only commercial installations ever need this.

So don't go randomly picking IP ranges.  🤣 Just change the 3rd digit so they are not he same at the router and modem.