Orbi WiFi 7 RBE973

Subnetting with Netgear C3700 under Xfi Gateway


Subnetting with Netgear C3700 under Xfi Gateway

I've been trying to create a sub- network under my Xfinity gateway utilizing my old Netgear C3700 router..The Subnett is two IP cameras connected to the two ethernet ports on the c3700 and a windows 10 machine connected through the c3700s Wifi. I would like this network to have access to the Internet through the Xfinity Gateway by some wireless means. Ive tried creating a windows MAC Bridge (software bridge) to accomplish this but end up with intermittient Internet and WiFi connectivity. Ive tried turning off Router Mode on the C3700 but then I just cant find it anywhere after I do. Ive read what seems like maybe 10% of the Internet for weeks now trying to figure the tiny bit of syntax I'm not getting right, or maybe I don't understand the architecture quite right. I have attached a drawing of my ideas for reference.


If anyone would be so kind as to tell me how utterly wrong I am and what I should be doing differently I would be greatful.




<h2> SUBNET </h2>
<img border="0" src="SUBNETresize.png" alt="Subnet" width="600" height="287" />

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Model: C3700|N600 Cable Gateway Docsis 3.0
Message 1 of 3

Re: Subnetting with Netgear C3700 under Xfi Gateway

Your problem is the C3700 is a modem/router combo device. It isn't a wireless extender, repeater. 

The C3700 doesn't have an extender mode and if you disable router mode, it functions as purely a modem only device. 


You can turn the c3700 into a type of access point but it'd still need to be hardwired in. 



Your trying to cobble together a system with parts not designed for what you're attempting. 

Current setup: CM2000-> RBE973S-> Trendnet TEG-S380-> GS716T-> pi-hole
also in AP setup: RAXE500->EAX80
1.4gig download/100mbps upload from Xfinity
We’re members of the public helping out on our own time.
Message 2 of 3

Re: Subnetting with Netgear C3700 under Xfi Gateway

YOu can try configuring the modems LAN side for a IP address that you use on the XFI gateway, turn OFF DHCP on the modem, connect up the modems LAN port to the XFI gateway. Use the preconfigured IP address to access the modems web page. 

My Setup ISP SparkLight | Internet Cable 1000↓/50↑ CAX80 Modem Mode  | Wifi Router RBE971 | Switches NG GS105/8, GS308v3, GS110MX and XS505M | Additional NG HW: C7800/CAX30/CAX80/CM1100/CM1200/CM2000, Orbi: CBK752, RBK50, RBK853, RBK752, RBK953, SXK30 | NightHawk: MK63, MK93S, R7000, R7800, R7960P, R8000, RAXE500, RAX120v2, RAX50v2, XR450/500/700/1000,

Message 3 of 3
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