[mythtv-users] UK 'top-up tv' - how?

[Jo Shields]

Paul Fowler wrote:
> I have my myth tv system working hapily with four DVB tuner cards (4x
> Twinhan DVB-Ter D+A model 3054) reciving the 'free' channels known as
> 'freeview'.
>
> Now I am interested in subscribing to top-up tv, and was wondering if
> this could be integrated into myth tv.
>
> None of my DVB cards have a CI interface so I was wondering if it is
> possible to attach the top-up tv CAM via a pcmcia interface and have one
> (or all) of the tuners (via driver) use it as necessary to decrypt the
> transmission stream.
>
> Alternatively is there a software cam which could talk to the
> subscription card and decrypt the transmission stream.
>
> I am guessing the can would appead as another device in
> /dev/dvb/AdapterXYZ and could be used in place of the conventional
> adapter ?? Just a guess, don't shoot me down ;-)
>
> Also, if any of the above is possible, is it also possible to decrypt
> more than one stream at a time using just one subscription and CAM. If
> not then can scheduled recordings be postprocessed to decrypt for later
> viewing.
>
> I have no intention of receiving material which I have not paid a
> subscription to.
>
> Any help or comments would be gratefully received.
>
> Regards,
> Paul.
>   

Having run out of money, my new myth system lies half-finished. So all 
of the following is thought, not personally tried.

However, as best I understand it:

*CI is split into four layers - Application, Session, Transaction and 
Physical layers.
*Some or all of those layers are provided by hardware, some or all by 
software.
*Hardware which covers the last 3 layers (such as a Twinhan or 
TechnoTrend) in hardware, via a slot, should just work with Myth
*Hardware which is missing layers requires the host software to fill in 
the gaps - e.g. the Windows-only support for a NebulaTV card via 
http://www.nebula-electronics.com/TopUpTV.asp
*You ought to be able to record multiple channels on the same MUX from 
the same card, which includes multiple decrypted channels from one 
subscription

The question I've never seen answered is: does MythTV (or indeed Linux) 
support a software CAM driver fed a subscription via a smartcard reader? 
I don't know. I bought specific hardware to avoid the question.