Tektronix PowerPoint Template - AVIT

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Establishing and Maintaining
Broadcast Quality Video over IP
Yannick LE DREAU
4 September 2010
Agenda
 Attracting and retaining subscribers
– What can we realistically do to maintain the best delivery quality to our
subscribers ?
– What do we mean by Quality of Service and Quality of Experience ?
 The IP Video Ecosystem
– Garbage in, Garbage out
– What can we measure and how ?
 A system wide view - where do we look and what do we look at ?
 Putting it the Big Picture together
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–
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Finding and resolving customer impacting issues quickly
Using distributed monitoring and diagnostics
Element/Network Management systems
Proactive, not reactive; keep your subscriber away from his phone
 Conclusion
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Establishing and Maintaining Broadcast Quality Video over IP
Attracting and retaining subscribers

What are subscribers REALLY interested in ?
– Getting the right program
– Good picture quality
– Synchronised audio and video

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All these factors impact Quality of Experience
(QoE)
Establishing and Maintaining Broadcast Quality Video over IP
Quality of Service & Quality of Experience
 Quality of Service (QoS)
– In network traffic engineering, QoS can be used provide various priorities
to differing data flows, or guarantee a certain level of performance to a
data flow.
– In IP Video systems, this prioritization is critical to achieve good quality
service delivery.
– Can be objectively measured by the provider himself
 Quality of Experience (QoE)
– Closely related, but subtly different
– Focused on the overall performance of the delivery system from the endusers perspective.
 QoE is a subjective measurement of the perceived value of the overall
service, and customer experience.
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Establishing and Maintaining Broadcast Quality Video over IP
Quality of Service & Quality of Experience

QoS and QoE are inextricably linked !

Increasing video compression reduces bandwidth
and can therefore improve QoS

The end user perceives lower quality video,
therefore QoE is reduced
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Establishing and Maintaining Broadcast Quality Video over IP
IP Video Ecosystem
IPTV Ecosystem
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Establishing and Maintaining Broadcast Quality Video over IP
The primary functions of the IP Video headend
 Digital program acquisition:
– Content from the satellite or terrestrial sources, and the preparation of
that content for digital delivery (National or regional).
 Digital program storage:
– Storage and insertion of additional, non-live broadcast programming like
local content, video-on-demand or advertising.
 Digital program distribution and delivery:
– Program preparation and aggregation, rate-shaping, modulation,
encapsulation (encoding), encryption and other technical processes for
program delivery.
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Establishing and Maintaining Broadcast Quality Video over IP
IP Video Headend
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Establishing and Maintaining Broadcast Quality Video over IP
Headend Ingest - RF

Various RF parameters can be proactively
used to measure RF signal quality;
– Modulation Error Ratio (MER)
– Error Vector Magnitude (EVM)
– Bit Error Rate (BER)

MER particularly is defined as a ‘single
figure of merit’ of the RF signal

Measurement trending can be used to
identify signal degradation
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Establishing and Maintaining Broadcast Quality Video over IP
Headend Ingest – IP traffic

QoS refers to the ability of a service
provider to support users’
requirements with regard to at least
4 service categories;
–
–
–
–
Bandwidth
Latency or delay
Jitter
Traffic Loss
Measurement
Category
Key Performance
Indicators
Bandwidth
Total Line Bitrate
IP Session Bitrate
TS Bitrate
Program Bitrate
PID Bitrate
Latency/Delay
Max/Min Packet Inter-arrival
Time (PIT)
Jitter
Max/Min Packet Inter-arrival
Time (PIT)
PCR_OJ, PCR Inaccuracy
PCR-PTS values
Traffic/Packet Loss
RTP Lost Rate/Count
RTP Out of Order Rate/Count
Frame Checksum errors
TS Continuity Count errors
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Establishing and Maintaining Broadcast Quality Video over IP
Headend Ingest - SDI

Multi source, multi format feeds need to
be checked as they are brought into the
plant.

Origination may be 3G-SDI

Rapid problem location by tracking
video presence and format, luma and
gamut errors, and CRC statistics.

Comprehensive audio information
including clips, mutes, over and silence
conditions can be summarized by
individual audio channel.
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Establishing and Maintaining Broadcast Quality Video over IP
Headend Ingest – File Based

Multi source, multi format feeds need to be checked as they are brought
into the plant.

Using automated file-based QC solutions can reduce your end-to-end
file time, reduce the number of people in the workflow, and reduce churn
by having your content accepted the first time.

Automated QC can scale with content growth, increase service quality,
and get better leverage out of existing staff.
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Establishing and Maintaining Broadcast Quality Video over IP
What and where can we
measure ?
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Establishing and Maintaining Broadcast Quality Video over IP
What can we measure – QoE Metrics
 It is important to look at subjective customer impacting issues such as
video and audio impairments.
 These are the QoE issues most likely to cause customer
dissatisfaction, increase churn and therefore directly impact ARPU.
 Video impairments include;
–
–
–
–
–
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Stuck/Frozen Video detection
Black Video detection
Blockiness and slice error detection
Tiling/pixelization detection
Display of video metadata; codec type, resolution, display area, aspect
ratio, bit rate, Frames per second, scan and AFD
Establishing and Maintaining Broadcast Quality Video over IP
What can we measure – QoE Metrics

Using these video measurements, it is possible to isolate encoding issues
from transport issues

Examples;
– Tiling effects are typically caused by insufficient bit-rate for required image detail
rather than any TS stream defect (PCR errors, dropped packets, etc).
– Blockiness artifacts are typically due to data loss - dropped packets, PCR jitter, or
TS format problems. Normally very noticeable.
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Establishing and Maintaining Broadcast Quality Video over IP
What can we measure – QoE Metrics

Audio impairment measurements should include;
–
–
–
–
–
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True Peak & Loudness (ITU-1770/1771)
Clipping
Silence detection
Detection of phase problems
Display of audio metadata including codec type, number of channels, bit rate and
sample rate.
Establishing and Maintaining Broadcast Quality Video over IP
Quality of Experience Monitoring:
Video & Audio QoE scoring
 Score hundreds of video and audio streams, based on customers’
experiences (QoE), in real time continuously & simultaneously
Screen capture of a video clip with low VQoE score
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Establishing and Maintaining Broadcast Quality Video over IP
IP Video Quality Measurements (Who Cares)
Visual
Control Measures
Control
IGMP Latency, RTSP Latency, Channel
Zap Time
Content
MPEG-TS
RTP
Content Measures
Picture Quality, Blocking, Blurring,
Visual Noise, Audio Drop-outs
Media Transport Measures
PCR Jitter, Pixelization,
Sync Loss, Continuity Errors
UDP
IP
Physical
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Ethernet
QoE
Customer
IP Network Measures
Packet Loss, Jitter, Delay
Establishing and Maintaining Broadcast Quality Video over IP
QoS
Network
Engineering Troubleshooting
QOE/QOS Correlation
 Time-based root
cause analysis
Bit rate
 Triggered capture
capability
Audio/Video QoE
Audio loudness
 60-day historical
report
Discontinuity event
IP statistics
 By program
Splicing event
 By location
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Establishing and Maintaining Broadcast Quality Video over IP
Where can we measure ?
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Establishing and Maintaining Broadcast Quality Video over IP
Taking a system wide view
 It has been shown that automated conformance checking and
monitoring is possible across all types of ingest.
 Any point where content is changed is a possible failure point;
– Re-multiplexing
– Transrating & transcoding
– IP encapsulation and transmission
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Establishing and Maintaining Broadcast Quality Video over IP
QoE Monitoring & Reporting
Dashboard, Alert Analysis By Program/Location
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Establishing and Maintaining Broadcast Quality Video over IP
Putting the Big Picture together
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Establishing and Maintaining Broadcast Quality Video over IP
Putting the big picture together

Using distributed monitoring probes can supply cross layer QoS/QoE metrics.

Operators need the ability to ‘tune’ the system to give focus to high priority
assets.

How can you collate and sort all the information from these probes in order to
quickly isolate problems ?
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Establishing and Maintaining Broadcast Quality Video over IP
Putting the big picture together
 An Element Management System (EMS) can give several layers of
features;
 Engineering
– The ability to identify impacted services and enable engineers to drill
down for rapid root cause analysis of video service delivery issues is key.
– Providing alarms, logs, trending and reporting of key performance metrics
 Operations
– Ability to view video from any probe within the network
– Inclusion of integration for STBs or other Customer Premises Equipment
(CPE) in order to provide diagnostics from the subscriber network.
 Management
– Provide key video and audio impairment data
– Are we meeting our SLAs ? Are our providers meeting theirs ?
– Use service data to be proactive; act before your customer does
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Establishing and Maintaining Broadcast Quality Video over IP
Putting the big picture together
 It can provide managers with the ability to track both network and
service performance;
– Support for reporting through statistical logging and report generation
– Trending analysis for tracking of management performance metrics and
service level agreements.
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Establishing and Maintaining Broadcast Quality Video over IP
Conclusion
 It is clear that carrying high quality digital video across IP networks is
a challenging task.
 Differentiated IP services such as High Speed Data, VoIP and video
all have differing bandwidth and QoS requirements.
 Video requires high availability (in bandwidth and time) which requires
implementation of robust network management policies, along with
suitable monitoring tools to ensure those policies are maintained 24/7
 It has been shown that IP video cannot survive in a “Best Effort”
environment - video packets need to arrive in sequence and with no
losses.
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Establishing and Maintaining Broadcast Quality Video over IP
Conclusion
 Use of test equipment in this environment is essential and correctly
placed monitoring probes across the network can provide important
data in the form of KPIs for both QoS & QoE
 Combined with the use of EMS/NMS, this can empower operators and
engineers to efficiently manage network systems.
 This can prevent degradation of signal quality which may result in
errors which affect the end users experience and ultimately, Operator
revenues.
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Establishing and Maintaining Broadcast Quality Video over IP
Questions?
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Establishing and Maintaining Broadcast Quality Video over IP
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