Coax Home Networking - Part 1

As one of many people who live in a rental townhouse, with no ethernet wiring but lots of coax going to almost every room, and not having real freedom to cut too many holes in the walls, I'm motivated to seek out the best possible way to extend my network throughout my home using alternate means.

I have wireless N capability, but I find it just not quite reliable or fast enough for things like system backups and copying large files like videos. Both of my Wireless-N equipped laptops regularly lose connection to the N network and need to be rebooted to get it back. Powerline networking has proved reasonably reliable, as long as you don't run laundry (or a vacuum cleaner, or a microwave, or a hair dryer... but I digress), but just as slow as wireless - sometimes even slower. This leaves those plentiful coaxial cables as the most promising alternative, so my research into ways to harness these beasties has begun.

To give some background, there are (big surprise!) two competing standards for coaxial cable networking that deliver workable speeds and warrant evaluation. These are HomePNA and MoCA. A simple google search for either of these will bring up the HomePNA Alliance or Moca Alliance home pages. After wading through the marketing fluff, it is simple to find links to actual products that are either shipping or almost there.

Interestingly, several companies, such as 2wire, Actiontec, and Motorola, seem to be present in both camps, and shipping compliant products on both sides.

To give this stuff a real world try, I was able to get my hands on a set of four Ready-Links CEB-402 ethernet-to-coax bridges, and also a set of four Motorola NIM100 ethernet-to-coax bridges. The Ready-Links supports HomePNA while the Motorola supports MoCA.

The Ready-Links I was able to purchase right online from the manufacturer, and have found their support people to be eager and helpful via email. The Motorola NIM100, on the other hand, is another matter entirely. If you search Motorola's web site, it is as if the NIM100 doesn't even exist. It seems Motorola only sells these devices directly to cable operators. I was able to get mine from a liquidator on eBay. They came in a nice box with all necessary cabling and no manuals whatsoever. Thanks to the very good DIY blog entry at http://lemmingreviews.blogspot.com/search/label/NIM100 about the NIM100 I was able to at least gain access to the machines enough to configure them. Shame on Motorola for being so cagey about this device. One can't help but notice it runs Linux and Busybox, and one does wonder what is the status of Motorola's GPL compliance on this device, and whether that is the reason for the secrecy. In contrast, Ready-Links provides a configuration utility for the CEB-402 which gives a nice view of the network status and provides a facility for firmware upgrades and network topology reporting.

For my setup, I hooked one coax bridge to my gigabit ethernet switch in the basement, connected it to a cheapo four-way coax splitter, and hooked the other three connections on the splitter to coax cables that go to the three bedrooms on the upper floor. In each bedroom, I put another bridge and a computer. This coax setup is not connected in any way to the cable TV feed into my house - although this will work, I wanted to just keep it separate for testing.

Testing involves both daily usage, and also performance measurement using iperf. I have been running the Ready-Links bridges for almost a year in this configuration, and am just beginning to test the NIM100's now. In the next post or two I will give details of my experience with these devices.