CI+ PVR on twin-tuner platform

[tomek]

Hello,

I'm trying to figure out how to implement PVR functionality on typical twin-tuner PVR box. I've got 2 major problem areas. First is the twin tuner itself. Second is that many things happen at the (unattended) recording recording time, not at the booking time. Could anyone help me and answer some of the questions below, please?

Q1: The spec doesn't say how to play back a CI+ recording. Is there a silent assumption the box will record a stripped-down transport stream and play it back via CAM later? Recording without play back capability is not of much use.

Q2: When user books a recording, the host should be able to ask CAM whether the user is actually entitled to watch the to-be-recorded programme, otherwise recording doesn't make much sense. Finding it out later by the user would be very annoying. How to check entitlements at the booking time?

Q3: How to watch and record at the same time using single CAM? In theory CAM is only involved in describabling the service user wants to watch, but in order to initiate recording host sends ca_pmt followed by ca_pvr_pmt. Is host supposed to use ca_pmt_list_management "add" value for ca_pmt and "first/more/last" or "only" for ca_PVR_pmt? This, in theory could work, but it's unspecified.

Q3: User may watch a programme from one multiplex while recording something from the other multiplex (using the 2nd tuner). Is it valid to send CAT, PMT, EMM, ECM, and so on from the 2nd multiplex to the CAM that's descrambling a programme from the first multiplex? Is it valid to send ca_pmt command containing PIDs from a transport stream that is not routed through the CAM?

Q3: The ca_pvr_pmt_reply may return status "conditionally possible" that involves MMI dialog. The problem is that recording is typically unattended so user won't be there to answer CAM's question. Is there any way to ask the question at the time of booking the recording?

Q4: There are some unspecified fields:
* ca_pvr_cat_reply::table_id - unspecified, what is it?
* ca_pvr_cat_reply::extra_filtering - what should host do with this data?
* ca_pvr_emm_cmd::EMM_section_filtering - unspecified, what exactly should be sent?
* ca_pvr_emm_cmd_reply::status - what the host should do with this data?

Q5: The ca_pvr_emm_cmd_reply doesn't contain re-encoded EMM, so what's the purpose of the ca_pvr_emm_cmd?

Q6: How to use the PIN management facility? What's the PIN needed for when the recording starts? How to check the PIN will actually be needed and ask user about it when he makes a booking? How to verify the PIN entered by the user is valid? PIN verification when recording starts is way too late. User will most probably find out the PIN was wrong when he finds out the recording is useless.

Thanks in advance,
Tomasz Bury

[tomek]

Two more questions:

Q7: What is supposed to be sent to CAM in trick modes, for example during the rewind and who is responsible for ECM management, host or CAM?

Q8: Is "tune" and "replace" allowed during recording? How to handle that?