IPTV Zapping Overview
Note: IGMP and Channel Zapping
IGMP is a signaling protocol that enables each STB to obtain only the programming that the viewer is
interested in watching, thus conserving bandwidth in the access network. STBs use the 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 for
more info.
IPTV Viewer -
displays the Picture and is useful as a channel identifier.
Channel
- Unicast or Multicast including IP address and UDP port #
Status
– Decoding please wait. Please allow 20-30 seconds for buffering and decoding to occur.
Physical Layer and Protocol Stack Troubleshooting Concept
5.7 Optical Power Meter (OPM)
With its optional Optical Power Meter, the LX100 is an ideal tool to troubleshoot FTTH and PON Networks. The standard power
meter can be used to verify the physical layer (optical power level) while the Advanced PON Power Meter functions allows in-
service measurement of bidirectional signals between OLT and ONT using an industry standard 2x2 optical coupler.
LX100 e-Manual D07-00-019 Rev A01
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