FiOS TV from Verizon uses a new Home Networking technology based on MoCA, a Standard defined by a consortium of companies. The founding company of this consortium, and MoCA Pioneer, is Entropic Communication which sports the venerable Andrew Viterbi as one of the Board Members.
This Technology Converts regular Ethernet traffic to a Signal that is able to traverse the COAXial wiring infrastructure already existent in most of the homes without affecting the Cable, Satellite or FiOS TV signal.
Multiple Nodes/Devices can be hooked to the same COAXIAL infrastructure and communicate in a mesh like topology on the shared medium.
In order to be able to make multiple devices communicate over the same medium and maintain Quaity of Service by avoiding packet collisions, one of the nodes elects himself as arbiter of the network and tells everybody when they can transmit and when they can not transmit.
In order to increase the available throughput of the network, each node can talk with each other directly avoiding wasting bandwidth by going back and forth to/from a centralized access point.
A 50 MHz portion of the spectrum in the 950MHz (MoCA WAN) 1150MHz (MoCA LAN) vicinity is reserved for communication among the different MoCA nodes. The 50 MHz channel is divided in 256 sub-channels. Each sub-channel communicates using the best modulation possible starting from BPSK up to 256-QAM.
Every node will negotiate the best modulation profile that can be achieved while maintaining a low Packet error rate for each of the nodes, the result is a logical mesh network between each node with different bit-rates for each unidirectional path.
In order to effectively Multi-cast or BroadCast packets destined to more than one node, the lowest common denominator profile is used so that all the nodes can receive the communication correctly.
Up to 8 networks (50 MHz each) can co-exist on the same wiring infrastructure without interference.
The result is a reliable backbone for Home Networking which at current state of the art can support a total troughput of around 150 Mbps.
Verizon uses regular Cable TV channels to broadcast TV to all users of FiOS TV which are hooked to a Fiber Network. The architecture for sending broadcast TV works similarly to current HFC (Hybrid Fiber Coax) Cable networks but the fiber reaches the home of the end user and the signal is converted back to coax directly in the home.
So, why Verizon uses MoCA technology?
While Broadcast Television does not require to be transported over ethernet, Video on Demand requires both:
- The ability for a user to request for a particular program.
- The ability for Verizon to send a program to a specific User.
So, for VoD Verizon uses this backbone Home Networking technology to carry the traffic associated with the VoD request and the VoD stream itself.
What are the important advantages of this technology?
- Coaxial Cables are already installed in the Home
- Coaxial Cables are already used to carry the TV signal to the TV sets and STBs.
Verizon originally had planned to use MoCA technology for the delivery of LAN traffic to all the Set Top Boxes in the house, but now two MoCA networks can be established in a FiOS installation in order to minimize installation costs by reusing existing wiring as much as possible. The result is that a MoCA domain is established between the Router and the different Set Top Boxes (MoCA LAN) and another domain (MoCA WAN) is established between the router and the ONT (Which is the box that converts the optical signal coming in the home from the fiber to regular Ethernet signal).
Below is a picture of a Typical Early installation of Verizon FiOS TV: (The MoCA technology is integrated in all Set Top Boxes and in the NIM100 a stand alone device which converts Ethernet to Moca)
Below is a picture of a Typical current installation of Verizon FiOS TV: (The MoCA technology is integrated in all Set Top Boxes and in the ONT, while 2 MoCA channels are embedded in the Brodband router.
NIM100 devices are being discontinued as routers from the early deployments get upgraded to the new Actiontec BHR with integrated MoCA and are becoming available from Liquidators on Ebay. Below is a picture of how one of these NIM100 devices coud be used in the current Verizon FiOS installations.
Full Article ...
