We have been trained and reinforced for decades that Ethernet rides over some form of Twisted Pair Cabling. If we are old enough, we might remember the ‘good old days’ of Thicknet or Thinnet Ethernet cable… but for most of our professional lives we have worked with Ethernet over twisted pair cabling. Starting with Cat3, Cat5, Cat5e, Cat6 and beyond.
But there is an entire other world of Ethernet over other types of copper cabling!
We’ll discuss a couple of these in this blog post.
MOCA – Multimedia over Coax Alliance
This technology is designed to re-use the coaxial copper cabling that exists in many homes, offices, and especially hospitality situations where the cost and hassle of bringing in new Twisted Pair Cabling might be prohibitive.
There is quite a bit of history with MOCA – nearly 15 years of using copper coax cabling to provide Ethernet.
Today’s new MOCA standards are getting quite competitive rates over standard, already installed, copper coax cables.
It uses the same types of modulation we use in the 802.11 Wi-Fi world of Quadrature Amplitude Modulation and is achieving speeds we can only dream of in Wi-Fi!
If you run into a situation where you may have pre-installed copper coax cable, you might want to check out some of the new capabilities offered by MOCA solutions!
This arena has been through a variety of technological solutions over the past two decades. Some of the previous solutions have come and gone.
All of these solutions relied on adding a modulated carrier signal on top of the existing AC wiring systems. Different types of power-line communications used different frequency bands. Since most power distribution systems were originally intended for frequencies of 50 Hz or 60 Hz, power circuits have a limited ability to carry higher frequencies. Propagation has been a limiting feature across all power-line Communications.
Many jurisdictions severely limited radio frequencies from unshielded copper wires – treating them as if they were radio transmitters.
After lots of starts and stops in various countries, what still exists today is the Home Plug Alliance solution.
Initially released in November 2001, the first powerline networking specification allowed devices to be connected via the home electrical wiring. It offered two versions – first at 14Mbps, then later superseded by the ‘turbo’ versions which reached 85Mbps.
Though they worked for basic web surfing and email, the technology failed when stressed with YouTube videos or streaming music.
The second release what HomePlug AV – delivering raw speeds up to 200Mbps. It was built from the ground up for entertainment purposes such as HDTV and home theater.
Next up is the HomePlug AV2 starting in early 2012 allowing for full gigabit performance over home electrical circuits. AV2 copes much better with today’s needs for high throughput and low latency needed for quicker response times. HomePlug AV2 is touted to bring up to 1.2Gbps and over wired copper circuits of up to 300 meters. Additionally, the Etherent ports are rated at Gig Ethernet speed.
With all technologies NOT over certified and verified Category 5, 5e or 6 cable plant, your mileage may vary! Be forewarned.
Please test your own copper cable plant with these solutions and test, test, test! We’ve found sometimes as little as 10% actual net throughput when compared with the listed specifications. But even in such situations, a 100Mbps consistent connection over copper cabling may provide more than enough net Ethernet bandwidth to meet your requirements.
We’ve talked about two alternatives to standard twisted-pair cabling that might help in situations where you don’t have access or budget for bringing in new Category 5 or 6 cable plant.