Reducing Peak Bandwidth for OTT Streaming

All rights reserved. © Bitmovin Inc 2019
April 2020
Reducing Peak Bandwidth for OTT
BITMOVIN | AKAMAI

The Presenters
Sean
McCarthy
Technical Product
Marketing Manager
Will
Law
Chief Architect
Akamai

1. Company introductions
2. Why reduce bandwidth?
3. What exactly are we trying to reduce?
4. 6 different techniques for reducing congestion
5. Summarized results
Agenda

Bitmovin’s Backstory
Chris Müller
CTO & Co-Founder
Stefan Lederer
CEO & Co-Founder
Summary
● Company founded in 2013
● PhD Research on MPEG DASH
● YCombinator 2015
● 30+ US Patents
● Athena Research Project
Solutions
ENCODER PLAYER ANALYTICS

Elevate
Viewer
Experience
Increase viewer
satisfaction by
exceeding expectations
on video quality
Operational
Optimization
Control cost, mitigate risk
and better manage
complexity
Faster Time
to Market
Get assets, products and,
services to market faster and
more efficiently

PLAYER
Reach viewers on largest number of devices
using a multi-device player. It’s flexible and
easy to deploy, utilizing built-in SVOD and
AVOD features, giving complete control of
the viewing experience.
ENCODER
Deliver content in the highest quality at the
lowest streaming costs. Prepare content at
high speed and deploy in any environment.
ANALYTICS
Fix playback issues with real-time data before
your viewers see it. Monitor infrastructure
performance insights, anytime, all the time.
Visualize data, your way.

Over half of all Fortune 500 companies
68 of the world’s largest OTT services
All top 25 publicly traded global gaming companies
All top 50 global carriers
Over 500 banks worldwide
TRUSTED BY THE WORLD’S LEADING BRANDS
56 million hits per second
3 trillion deliveries per day
167+ terabits per second
ACCELERATING DAILY TRAFFIC OF
Akamai’s Edge Platform: Making A Big Difference
285,000
SERVERS
1,500
NETWORKS
4,100
LOCATIONS
136
COUNTRIES
1,000
CITIES

Media Performance Web Security
Zero Trust IoT Blockchain
Business Drivers… and the Next Wave

Global Akamai Traffic is Up
~30% Over the Last Month
(Compared to ~3% Growth for a Typical Month)

1 Tbps67
Peak Traffic on Akamai’s
Edge Platform Doubled Y/Y
March 2020
Tbps82March 2019

COVID-19’s Impact on Streaming
Viewers are watching
more and are watching
longer

All rights reserved. © Bitmovin Inc. 2019
Video Bitrate The graph shows a time series of the Average Video Bitrate consumed by viewers
COVID-19 Case Study — African OTT Provider

©2016 AKAMAI | FASTER FORWARDTM
Where is the congestion?
ORIGIN
PEERING
POINT
Autonomous
System
Autonomous
System
Autonomous
System

Where is the congestion?
CMTS
DSLAM
CDN
CDN
CDN
CDN
ORIGIN

Volume and Peaks
CONGESTION
Flatten the curve! Reduce the volume
TIME
Bandwidth

Wait a moment. ….
Don’t Adaptive Bitrate players and TCP
algorithms negotiate down to a fair-share of
capacity all by themselves?
We don’t have to do anything!!!
The congestion will resolve itself.

Not actually a crazy suggestion
However in the real world some things conspire to prevent fair share
usage.
1. Not all flows are adaptive – you video is sharing every connection
alongside gaming downloads, software updates, API calls and
website delivery.
2. Traffic is a mixture of protocols – H1, H2, H2+QUIC, UDP, H3 ..
3. The ability of a protocol to fair-share is dependent upon the
congestion algorithm being used. There are 5 congestion algorithms
used within Akamai alone today – BBR, FastTCP, Reno++, QDK,
Cubic. Competing flows may use other protocols.

Protocols affect performance
Simulating segmented media delivery with a 1s pause
BBR
FastTCP
Black: Background Download using FastTCP CC
Red: Foreground Download using BBR CC

What do we want to do then?
Irrespective of the protocols being used, if
we reduce the volume of traffic being
delivered and/or the peak data rate, we
will have a corresponding reduction in the
likelihood of congestion.

Methods to reduce peak bandwidth consumption
1. Utilization of CAE encoding
2. Utilization of Improved codecs
3. Content provider removing top bitrates from manifests
4. Players limiting top bitrate in unmodified manifests
5. CDN dynamically modifying manifests as it delivers them
6. CDN throttling download rates
We will demonstrate the application and effectiveness of each of these
solutions by deploying them in turn against a baseline MBR HLS stream.

BASELINE video – encoded by Bitmovin,
delivered by Akamai

○ Bitrate too high - wasteful (especially CDN,
storage) and potential QoS delivery issues
○ Bitrate too low - visual artifacts, viewers less
engaged, churn and market share loss
Per-Title Encoding - Enabling Contextual Awareness
24
Not all content is created equal, why encode it the same?

25
○ Complexity analysis built-in in encoding step
○ Bitrate ladder boundaries fully configurable by user
■ Upper limit for highest bitrate
■ Lower limit for lowest bitrate
■ Number of renditions
■ Step sizes between renditions (SD, HD, UHD)
Per-Title Encoding - “How”
Patented algorithm to analyze complexity and adjust
encoding profile and ladder
● Complexity analysis performed in encoding step
● Programmable/Flexible “Black Box”:
○ Upper and lower limits for bitrates and resolutions
(up to UHD)
● Automatically creates optimized ladder by specific
asset
● Ladder optimized by size/bandwidth and picture
quality
● Reduces overall total cost of ownership (TCO),
especially CDN and storage
“Not too hot, not too cold, just right”

26
Per-Title Encoding - Example

Per-title (CAE) version – encoded by
Bitmovin, delivered by Akamai

Another Method: 3-Pass Encoding
28
■ Same avg. bitrate
■ Significantly improved quality due to optimized encoding
settings and pre-processing
Bitmovin 3-pass
Avg. bitrate 2,200 kbps
Standard
Bitmovin 3-pass
Standard
■ Same visual quality
■ 30% less bitrate

Codec Efficiencies Compared to H.264
HEVC
40%
More efficient than H.264
VP9
40%
AV1
70%
E.g. a HEVC encoded file will use 40% less bitrates than a H.264 encoded file

Adjust, optimize and deliver
Understand your device support
40-50% Higher Efficiency

Multi-Codec + Per-Title Bandwidth Savings

VP9 version – encoded by Bitmovin,
delivered by Akamai

Manually removing top bitrate on server side
#EXTM3U
#EXT-X-INDEPENDENT-SEGMENTS
#EXT-X-VERSION:8
#EXT-X-MEDIA:TYPE=AUDIO,GROUP-
ID="audio",NAME="en",LANGUAGE="en",URI="audio_en.m3u8"
#EXT-X-STREAM-INF:BANDWIDTH=5861018,AVERAGE-
BANDWIDTH=2191664,CODECS="avc1.640028,mp4a.40.2",RESOLUTION=1690x720
,AUDIO="audio",CLOSED-CAPTIONS=NONE
video_720pp_2000k.m3u8
0,AUDIO="audio",CLOSED-CAPTIONS=NONE
BANDWIDTH=1181295,CODECS="avc1.64001F,mp4a.40.2",RESOLUTION=1268x540
BANDWIDTH=665588,CODECS="avc1.640015,mp4a.40.2",RESOLUTION=564x240,A
UDIO="audio",CLOSED-CAPTIONS=NONE
#EXTM3U
#EXT-X-INDEPENDENT-SEGMENTS
#EXT-X-VERSION:8
#EXT-X-MEDIA:TYPE=AUDIO,GROUP-
ID="audio",NAME="en",LANGUAGE="en",URI="audio_en.m3u8"
BANDWIDTH=1181295,CODECS="avc1.64001F,mp4a.40.2",RESOLUTION=1268x5
BANDWIDTH=665588,CODECS="avc1.640015,mp4a.40.2",RESOLUTION=564x240,
AUDIO="audio",CLOSED-CAPTIONS=NONE

Version in which the master playlist has
been edited on the server

Modifying the player via the API to limit the top bitrate
It is possible to deliver a full playlist to the Bitmovin player, but then use the
Player API to instruct it never to switch up beyond a certain quality level.
See: https://github.com/bitmovin/bitmovin-player-web-samples/blob/master/adaptation/DynamicallyLimitBitrate.html#L147

Player API usage to limit top
bitrate that is played

CDN Manifest Personalization
• Akamai can filter the bitrates in your
master HLS playlists as it delivers them.
• This filtering operation can be driven by
configuration settings, or it can be
dynamically applied via query args on the
playlist request.
• Filtering can be adjusted by
• Query arg
• Geo location
• Time of day
• UserAgent
• Content path

CDN modifying the playlist to remove the top bitrate

CDN throttling – Tech Preview feature
• CDNs nearly always deliver content as fast as possible.
• In the prior examples, the 8.7Mbps media segments were being delivered at 136
Mbps, which is 15x faster than they need to be. The connection between client
and server is 94% idle.
• If we throttled delivery to some reasonable multiple of the top bitrate, then
• Peak bandwidth usage would be reduced.
• The player would still switch up to the top bitrate and users would see the same quality.
• Player buffer would build to the same level, so rebuffer rates should be similar.
• Buffer-bloat on last mile networks might be reduced.
• Traffic through CDN and last mile would be smoother.
• Competing HAS players would see more stable throughout estimates.
• What’s a reasonable multiple? – somewhere in the range 3x – 5x.

CDN throttling approach from Akamai

Results – comparison between methods to reduce volume
and peak bandwidth consumption of OTT content
Method Mbytes
transferred1
Percent reduction
in Mbytes
Average
Download Rate2
Percent reduction in
Avg download rate
SSIMPlus score
seen by end user
Change requires access
to these components
Baseline – AVC standard
encode with fixed ladder 68 - 134 - 85 -
1: Utilization of CAE
encoding 26 61% 136 0% 85 Encoder, packager or origin
2: Utilization of Improved
codecs 34 50% 144 0% 86 Encoder, packager or origin
3: Content provider
removing top bitrates from
manifests
45 34% 138 0% 82 Encoder, packager or origin
4: Players limiting top bitrate
in unmodified manifests 45 34% 136 0% 82 Player
5: CDN dynamically
modifying manifests as it
delivers them
45 34% 124 0% 82 CDN
6: CDN rate limiting delivery
70 0% 19 85% 85 CDN
1
For first 30s of example stream. 2
Dependent on last mile connectivity & edge server location

Reducing Peak Bandwidth for OTT Streaming

Recommandé

Recommandé

Contenu connexe

Tendances

Tendances (20)

Similaire à Reducing Peak Bandwidth for OTT Streaming

Similaire à Reducing Peak Bandwidth for OTT Streaming (20)

Plus de Bitmovin Inc

Plus de Bitmovin Inc (20)

Dernier

Dernier (20)

Reducing Peak Bandwidth for OTT Streaming