[linux-dvb] Re: Troubles with DVB-C

[Holger Waechtler <holger@qanu.de>]

Robert Schlabbach wrote:

> From: "Philippe" <gaultier.philippe@free.fr>
>  
> > Well, I think that for digital cable, each frequency carrying
> > some channels is called a transponder.
> >    
> No, "transponders" are only used in satellite systems. But since digital
> satellite was established first, many were used to calling those things
> "transponders" and didn't bother to switch to the correct term when digital
> cable and satellite was introduced.
>
> The general term is "multiplex", which means a transport stream regardless
> of the specific transmission method.
>
> The specific terms are "transponder" for satellite, and "channel" or
> "frequency" for cable and terrestrial transmission.
>
> So if you don't want to bother using the specific term, just always use
> "multiplex".
>  
not entirely correct: http://en.wikipedia.org/wiki/Transponder

Tronsponder is simply the term for a (re-)transmitter. Since in the 
context of DVB the multiplexed and transmitted stream contains a 
description of the transmitter (and thus has to be remultiplexed for 
this particular transmission channel) the words "Multiplex", 
"Transponder" and "Transmitter" all describe a defined stream 
transmitted on a particular frequency in a network, no matter if you are 
talking about DVB-S, DVB-T or DVB-C.

Holger