G.2 FEC Stream & Channel Bundling

26.3463GPPMultimedia Broadcast/Multicast Service (MBMS)Protocols and codecsRelease 17TS

Tools: ARFCN - Frequency Conversion for 5G NR/LTE/UMTS/GSM

G.2.1 Introduction

FEC Stream bundling is a method of improving the FEC efficiency and also to improve channel switching times. Several flows of one or more user services are "bundled" to form the source blocks for the FEC calculations. . This means, that all flows must be received for potential FEC recovery.

If flows from more than one user service are bundled (i.e. Channel Bundling), then the receiver discards other services after FEC processing. When a switch is performed, media inside the same bundle is immediately available. Stream Bundling can be performed on whole channels, parts of channels, or not at all.

Note: FEC Bundling does not improve start-up times.

G.2.1.1 Full Channel Bundling (All flows of several user services)

When full bundling is used, more than one complete channel is bundled. A channel switch inside the bundle does not require rebuffering and can therefore be near instantaneous. However, full bundling requires the processing of all packets. In other words, at a single time instance all video streams and all audio streams are received and processed. Also, the number of channels possible is limited by the fixed bearer bandwidth.

G.2.1.2 No Bundling

When no bundling is used, each channel is protected separately. In a channel switch the new channel needs to be buffered for the full min-buffer-time. At a single time instant one video stream and one audio stream is received and processed.

G.2.1.3 Partial Channel Bundling (Some flows of several user services)

Partial bundling may be used to combine some of the benefits of full bundling and no bundling. In this case more than one parital channel is bundled. This may be used to reduce the processing required on the terminal while retaining fast channel switching between parts of the media.

Partial bundling may be used to bundle only the audio part of channels. In other words, at a single time instance one video stream and all audio streams are received. When a switch occurs the audio is switched instantaneously as it does not need to be rebuffered. The complexity of this case is substantially lower than full bundling and the number of channels which can be bundled given a fixed bearer bandwidth is substantially increased. This is due to the fact that the audio uses a substantially lower percentage of the bitrate compared to video.

G.2.1.4 Stream Bundling (All flows of a single user services)

When stream bundling is used, all flows of a single channel are bundled. The FEC source block is formed using audio, video and security data.

Annex H (informative):
QoE Reporting Management Object Device Description Framework

This Device Description Framework (DDF) is the standardized minimal set. A vendor can define its own DDF for the complete device. This DDF can include more features than this minimal standardized version.

<?xml version="1.0" encoding="UTF-8"?>

<!DOCTYPE MgmtTree PUBLIC "-//OMA//DTD-DM-DDF 1.2//EN"

"http://www.openmobilealliance.org/tech/DTD/dm_ddf-v1_2.dtd">

<Man>–The device manufacturer–</Man>

<Mod>–The device model–</Mod>

<Node>

<NodeName>3GPP_MBMSQOE</NodeName>

<Get/>

</AccessType>

<node/>

</DFFormat>

</Occurrence>

<Scope>

</Scope>

<DFTitle>The interior node holding all 3GPP MBMS QoE Metrics Reporting objects</DFTitle>

</DFType>

</DFProperties>

<Node>

<NodeName>Enabled</NodeName>

<Get/>

</AccessType>

<bool/>

</DFFormat>

<One/>

</Occurrence>

<Scope>

</Scope>

<DFTitle>The QoE reporting requested indicator</DFTitle>

</DFType>

</DFProperties>

</Node>

<Node>

<Get/>

</AccessType>

<chr/>

</DFFormat>

</Occurrence>

<DFTitle>The Access Point Name for QoE reporting</DFTitle>

</DFType>

</DFProperties>

</Node>

<Node>

<NodeName>Format</NodeName>

<Get/>

</AccessType>

<chr/>

</DFFormat>

</Occurrence>

<DFTitle>The QoE metrics report format</DFTitle>

</DFType>

</DFProperties>

</Node>

<Node>

<NodeName>Rules</NodeName>

<Get/>

</AccessType>

<chr/>

</DFFormat>

<One/>

</Occurrence>

<DFTitle>The QoE metrics rules</DFTitle>

</DFType>

</DFProperties>

</Node>

<Node>

<NodeName>Session</NodeName>

<Get/>

</AccessType>

<node/>

</DFFormat>

</Occurrence>

<DFTitle>The QoE session metrics node</DFTitle>

</DFType>

</DFProperties>

<Node>

<NodeName>Metrics</NodeName>

<Get/>

</AccessType>

<chr/>

</DFFormat>

</Occurrence>

</DFType>

</DFProperties>

</Node>

<Node>

<Get/>

</AccessType>

<node/>

</DFFormat>

</Occurrence>

<Scope>

</Scope>

<DFTitle> A collection of all extension objects</DFTitle>

</DFType>

</DFProperties>

</Node>

<Node>

<NodeName>Speech</NodeName>

<Get/>

</AccessType>

<node/>

</DFFormat>

</Occurrence>

<DFTitle>The QoE speech metrics node</DFTitle>

</DFType>

</DFProperties>

<Node>

<NodeName>Metrics</NodeName>

<Get/>

</AccessType>

<chr/>

</DFFormat>

</Occurrence>

</DFType>

</DFProperties>

</Node>

<Node>

<Get/>

</AccessType>

<node/>

</DFFormat>

</Occurrence>

<Scope>

</Scope>

<DFTitle> A collection of all extension objects</DFTitle>

</DFType>

</DFProperties>

</Node>

<Node>

<NodeName>Video</NodeName>

<Get/>

</AccessType>

<node/>

</DFFormat>

</Occurrence>

<DFTitle>The QoE video metrics node</DFTitle>

</DFType>

</DFProperties>

<Node>

<NodeName>Metric</NodeName>

<Get/>

</AccessType>

<chr/>

</DFFormat>

</Occurrence>

</DFType>

</DFProperties>

</Node>

<Node>

<Get/>

</AccessType>

<node/>

</DFFormat>

</Occurrence>

<Scope>

</Scope>

<DFTitle>A collection of all extension objects</DFTitle>

</DFType>

</DFProperties>

</Node>

<Node>

<Get/>

</AccessType>

<node/>

</DFFormat>

</Occurrence>

<DFTitle>The QoE timed text metrics node</DFTitle>

</DFType>

</DFProperties>

<Node>

<NodeName>Metric</NodeName>

<Get/>

</AccessType>

<chr/>

</DFFormat>

</Occurrence>

</DFType>

</DFProperties>

</Node>

<Node>

<Get/>

</AccessType>

<node/>

</DFFormat>

</Occurrence>

<Scope>

</Scope>

<DFTitle>A collection of all extension objects</DFTitle>

</DFType>

</DFProperties>

</Node>

<Node>

<Get/>

</AccessType>

<node/>

</DFFormat>

</Occurrence>

<Scope>

</Scope>

<DFTitle>A collection of all extension objects</DFTitle>

</DFType>

</DFProperties>

</Node>

</MgmtTree>

Annex I (informative):
Void

Annex J (normative):
Schema