Weak Cable Modem Signal

Recently I encountered a problem where the link from my ISP to the cable modem was not working. A technician from Rogers determined it to be an issue with cable from the curb to my house. After he resolved, he mentioned that the signal to my cable modem was weaker than it should be. Since he was willing, I took the opportunity to discuss a few things with him.

In all likelihood, the weak signal is due to the extremely cable long run from across the basement where the cable line comes in and up to the 2nd floor and then across another room. The technician also said another factor could be the cable itself (over 15 years old). I decided that I should try to do something about this.

The first thing I wanted to do is relocate the cable modem to the basement to reduce the cable run. As I wanted to maintain a wireless presence upstairs, I needed to introduce a 2nd router. My plan was to have the routers each connected to a gigabit switch and the switches would be connected to complete the network.

Here is what I did:

Basement Router
- connect the cable modem to the WAN port of the router
- set the IP address to 192.168.1.1
- set up DHCP server
- optionally set up wireless with exactly the same settings as the upstairs router
- connect the router to the basement gigabit switch

Upstairs Router
- the WAN port should be empty
- set the IP address to 192.168.1.2
- set the gateway address to be 192.168.1.1
- disable DHCP server
- leave existing setting for wireless
- connect the router to the upstairs gigabit switch
- make sure the gigabit switches are connected

The setup works for me. When I checked my cable modem (192.168.100.1), I can see that the signal to noise ratio and the power level have improved. Unfortunately I did not plan ahead to test the real speed to the computers upstairs. Even though the ISP cable run is shorter, my network cable run is longer.

The next step is for me to replace some of the old cables.