Orbi mesh systems

If your modem has a built in router and wifi already, This would be a double NAT condition which isn't recommended. https://kb.netgear.com/30186/What-is-Double-NAT
https://kb.netgear.com/30187/How-to-fix-issues-with-Double-NAT
Couple of options,
1. Configure the modem for transparent bridge or modem only mode. Then use the Orbi router in router mode. 
2. If you can't bridge the modem, disable ALL wifi radios on the modem, configure the modems DMZ/ExposedHost or IP Pass-Through for the IP address the Orbi router gets from the modem. Then you can use the Orbi router in Router mode.
3. Or disable all wifi radios on the modem and connect the Orbi router to the modem, configure AP mode on the Orbi router. https://kb.netgear.com/31218/How-do-I-configure-my-Orbi-router-to-act-as-an-access-point and https://www.youtube.com/watch?v=H7LOcJ8GdDo&app=desktop 

You can still use your current modem, just configure it to one of the suggestions above. If it's working well for you, I would try option#3 first. The NG cable modem/router can be bridged for option#1. 

Look for what may work best for you for you size of home. 

https://www.netgear.com/orbi/default.aspx
https://www.netgear.com/orbi/wifi-systems.aspx

30 feet is recommended in between RBR and RBS to begin with depending upon building materials when wirelessly connected. https://kb.netgear.com/000036466/How-far-should-I-place-my-Orbi-satellite-from-my-Orbi-router

If you have devices that support AX mode then maybe, if not, then Orbi AC will be good for you unless you just want to future proof your house hold. 

Any progress on this? 

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Samtwo wrote:

I have a Netgear AC1900 WiFi cable router-modem. My ISP is Spectrum.

I need to add a mesh WiFi system; the Orbi systems seem like the best choice since they'll be compatible with the existing gear.

So I'll apreciate help in clarifying some points -

1) Do I need to replace the AC1900 or is it possible for the Orbi to plug into the modem?

2) The coverage is for a ~2,500 sqf home plus outdoors. Should I get a 2 or 3 component system?

3) Should I go with a WiFi 6 system or is it an overkill?

 

Thanks, Sam

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