Using an Old Router to Extend your Wifi

New Broadband Router

When a shiny new Broadband Modem arived in the mail (NetComm Wifeless NF18ACV), I decided to use the old Broadband router(a NetComm NF4V) to extend my wifi Network to remote parts of the house where the Wifi signal was week. This document describes how to do this.

Broadband Router as Switch

The term "Router" is not an accurate description of a Broadband Router. A btroadband router actually contains three capabilities all rolled into one:

Broadband Modem

Switch

Wifi Access Point

The trick to setting up the old Router as a Wifi Extender was to disable Capability #1 above and basically just use the old Router as a Switch and Wifi Access Point. So how did I do this?

Step 1: Physical Connections

I connected my new NF18ACV Broadband Router to the new fibre connection point which is in the hall cupboard at the front of the house. I got the new Broadband router completely configured and working - including the Wifi and phone line.

I then connected a Powerline Adaptor to LAN Port 4 of the NF18ACV Broadband Router. I also plugged in another Powerline Adaptor in a remote part of the house (my Bedroom). Unfortunately, my house is not wired with CAT6 Cable and therfore the Powerline adaptors were a good second choice. I then paired up the Powerline adaptors using the WPS buttons on the front of the devices and then tested the connection using a Laptop connected via Ethernet Cable to the Powerline Adaptor in the Bedroom. All good.

Next I connected the Powerline adaptor in my Bedroom to the WAN port of the old NF4V Broadband router using an ethernet cable. I then connected a Laptop to LAN Port 4 on the back of the old NF4V using another ethernet cable.

Step 2: Disable all existing WAN Configurations

I then logged into my old NF4V using the url: http:192.168.1.1. The new NF18ACV Broadband Router uses http:192.168.20.1. My old NF4V had three existing WAN connections configured as shown in the screenshot below. I deleted all three.

Step 3 - Configure a Layer 2 Eth Interface

Next, configure a layer 2 interface only for eth4. eth4 corresponds to the WAN port on the back of the Router. Eth0 to eth3 corresponds to the LAN ports marked 1 to 4. This is confusing because the numbers don't match up. But eth0 is actaully the physical LAN port marked 1 on the back of the device.

Step 4 Configure a Layer 3 IP over Ethernet WAN connection

The next step is to configure a WAN Service as shown in the screenshots below. I am using OpenDNS for Family safety. These are IP-Addresses 208.67.222.222 and 208.67.220.220. I deactivated IPv6 so as not to confuse OpenDNS (and me).

Below, I just selected an IP-Address of 192.168.20.100. The new NetComm Wifeless NF18ACV that arrived in the mail uses the 192.168.20/24 VLAN. So I just picked a high IP-Address in this VLAN that was unlikely to be used. I really should now go into the Console for the new Router and set this IP as a static DHCP lease address and tie it to the MAC address of the old NPF4 router. However it works fine without doing this. I might run into trouble if I have lots of devices and all the IP-Addresses between 192.168.20.2 and 192.168.20.100 get used up - then I might get an IP-Address conflict.

You should enable NAT on the next screen as shown below. Click on next and then Apply/Save on the following screen.

I tried it without NAT - but could not get a connection. NAT is Network Address Translation.

You should then reboot the Router which you can do via the GUI or by toggling the power button on the Router.

It should now work. You will now have two Wifi Networks in your house both of which will work and both will use two VLANS: 192.168.20/24 and 192.168.1/24. The VLANS will be connected together.

There are undubtable other ways of getting the Same Result. For example, you could use Layer 2 bridging which would give you only one VLAN. This might be easier to manage - but I spent about 4 hours on this and could not get it working.

You could also try and setup the second modem using Wifi Bridging. This would effectly make the old modem into a Wifi Repeater. I did not try this method either. I had some unused Powerline adaptors, and I thought I would get better throughput if I used a physical connection - rather then trying to bridge over Wifi.

I am now getting about 93 Mbps download and 11 Mbps Upload using an ethernet cable and about 50/9 using Wifi on 2.4 GHz. The new NF18ACV adaptor has both 2.4 GHz and a 5GHz reception. 5GHz is supposed to be faster (but shorter range). I am supposed to have 20 MBps from Trustpower - so I sense another phone call is imminent.

Documentation

Bride Mode Setup: https://support.netcommwireless.com/sites/default/files/BCS-NB604n.pdf

User Manual NF4V: https://support.netcommwireless.com/product/nf4v

OpenDNS IP-Addresses (Family Safety)

IPv4:

208.67.222.222

208.67.220.220

IPv6:

2620:0:ccc::2

2620:0:ccd::2