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magnushsi

join:2002-11-06
Cedar Springs, MI
reply to magnushsi

Re: how does a cablecard

said by magnushsi:

Actually you would be suprised how much CVC and others, do pay for boxes. Depending on the fee it's typically 2+ years (or more) for a cable company to pay for the box. Yes cable companies eventually make money on boxes, but it does take a while. You have to factor in warehousing, techs to stage, repair, etc.

Why is it the cable companies fault to come up with a standard? Its actually cablelabs responsibility. And they certainly did include a 2 way standard from day one. S-Cards have ALWAYS supported 2 way, DAVIC and DOCSIS. The CE vendors just failed to implement it.
I'm very familiar with how it was founded. So I will agree that cable companies are tied to cable labs, but so are CE vendors, software developers etc.etc.etc.

As far as a 2 way standard, thats not exactly correct, and I quote:

"The media has frequently reported that first-generation CableCARD 1.0 modules are one-way devices1. This is simply not true. CableLabs had always intended to develop the CableCARD module and host receiver standards with two-way capability. However the manufacturers of digital TVs requested that a host standard be developed that only had one-way capability. This one-way cable-ready receiver was defined by the FCC's Plug & Play order and by the Joint Test Suite (JTS). It is the definition of this one-way receiver that lacks the ability for two-way functionality, not the CableCARD module. While the FCC defined the elements of the one-way cable-ready receiver, CableLabs continued to define specifications for two-way receivers"

You are somewhat correct, there are 3 OOB communication protocols used by traditional cable companies, DAVIC 55-1, 55-2 and DSG. You can't say it was impractical, the major cablebox manufactures have boxes deployed that support those standards. Not true regarding certification. Depends on what they device was getting its certification for. More readind for you:

"There are three distinct languages (or protocols) that are used on cable systems for the two-way communications: (1) Aloha (the protocol, defined by the ANSI/SCTE 55-1 standard, used by Motorola systems); (2) DAVIC (the protocol, defined by the ANSI/SCTE 55-2 standard, used by Scientific Atlanta systems); and (3) DSG (the protocol, defined by the ANSI/SCTE-106 DOCSIS Set-top Gateway standard, used by a variety of cable systems). All three protocols transmit their upstream signals on channels in the 5 MHz to 42 MHz frequency band. In order for a Host to support two-way services on any cable system, it must be capable of transmitting upstream signals using any of the three protocols. Only products compliant with the OpenCable Host specifications include the transmitters capable of supporting all three upstream protocols. Products built to the Plug & Play or Digital Cable Ready (DCR) FCC requirements are unidirectional only, and do not include these transmitters and are unable to support two-way services.

On the other hand, CableCARD modules always were designed to support two-way functionality, including the original CableCARD 1.0 interface specifications. The CableCARD module includes the knowledge of the upstream transmission standards and protocols used by each cable operator and is able to format and prepare messages for that protocol. Those upstream messages are sent to the Host device for transmission (when so equipped). The upstream transmitter also is under the complete control of the CableCARD module to set frequency and output power. CableCARD modules are equipped to recognize the presence of these upstream transmitters in an OpenCable Host device and to use them as necessary. They also are able to detect the absence of this transmitter in a unidirectional Host and to operate in a one-way mode."

Tru2Way is NOT a 2 way communication protocol. ADSG is the communication protocol and it's been around for a while.