reconstruction of the program. The PID is used in conjunction with the Program Service Identifier (PSI) to
identify Program Association Tables (PAT) which in turn hold Program Map Tables (PMT). The PAT table is
also the table containing all program information ensuring the consumer receives updated program changes.
The PAT table lists all the programs in the transport stream and associates each program with another PID,
that holds a program map table (PMT) as its payload. PMT lists the Video, audio and eventual encryption
information. The Payload Structure Identifier (PSI) table needs to be consistent with the PID table. PAT and
PMT are inserted into the stream so that the decoder performs correctly. These two items should always be
present.
Pass Through - IPTV Scan
Pass Through - IPTV Viewer
IPTV Scan -
displays the
Scan
results;
Channel
- Channel number being scanned
Zap time (ms)
- Also known as inter-channel change delay. Time between a channel leave request is sent and the
receipt of the first byte of data from the new multicast channel. It is the IGMP Join L Channel Switch Delay (STB
dependent). Channel zapping should be < 700ms.
Status
- OK, no packet, Fail
Bandwidth
- Bandwidth associated with the stream
Note: IGMP and Channel Zapping
A signaling protocol that enables each STB to obtain only the programming that the viewer is interested in
watching, thereby conserving bandwidth in the access network as a result. STBs use IGMP to change
channels, by leaving and joining multicast groups representing channels. Key to IPTV QoE, is how fast and
reliably end users can change TV channels, also known as "channel zapping". Essentially it is calculated as
the time taken between sending a channel leave request and receiving the first video data of the new video
stream.
Refer to DSL Forum TR-126 Triple Play Quality of Experience (QoE) requirements
BX100A/V e-Manual D07-00-001 Rev E01
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