In Today’s OTT Competitive Landscape where OTT providers are looking to provide a sophisticated and user friendly UI and premium Catalogue ,a technical glitch or instability can lead to User Churn and Brand Erosion.

Let’s Say  Users  want to watch a movie or show which they were longing to watch and land on the OTT platform ,buy a subscription and click on the Play button and playback fails . This can make User dejected and can act as “ Churn Catalyst”

As an OTT Provider in this Competitive Market the aim should not be limited to Content Delivery but to Deliver Uninterrupted playback experience .

Let’s first dive into the Reasons of Playback Failures before we talk about the graceful handling which can done to deliver uninterrupted experience

Playback Error Categories

The Playback Error can be broadly categorized into following categories

Network Issues 

Network Congestion :A battle between throughput and Bandwidth .

• • • To explain this, let’s take an example of driving on Expressways. We all anticipate that using the expressways will reduce the travel time but there is always a case of traffic jams on expressways as well which eventually increases the travel time.
    • In Networking , vehicles are packets of data and when the arrival of packets exceeds the outgoing bandwidth of the network path . This leads to two cases
      • Possibility of Packets getting lost which leads to holes in the video
      • Possibility of Packets reached to player are out of order and player
        • In Both Cases the player needs to stop playback and start buffering.

DNS Failures

• This happens when the DNS provider is slow or experiencing an outage, the player sits in a “Pre-roll” state indefinitely.

Network Switching 

• During Playback , When User Network changes between Wifi to 5G/4G etc ,the IP address changes . As IP Address changes TCP connection changes thus the socket breaks and the request send by Player to the server is not recognised

DRM & Licensing –

DRM Integration :

For encrypted contents a request from the player is made to DRM for fetching License of the content  with token ,Once the license is fetched then player initiates the playback .

Failure in Handshake between Player and License Servers

• Token Send for fetching the license is Invalid or Expired
• License Fetch Failed : During request to DRM for License ,the License was received in the response to the request
• License Expired : During request to DRM for License ,the License was expired
• Clock Desync-If a user’s device time is manually set incorrectly, the “Time-to-Live” (TTL) on the security certificate fails, and the handshake is aborted.
• Security Level Mismatch :A 4K stream might require L1 Security (hardware-level). If the device only supports L3 (software-level), the server refuses to hand over the key
• Output Protection (HDCP): user initiated to play a content on an old monitor or through an unauthorized HDMI splitter that doesn’t support content protection

Source/Manifest Error

Failure Reason 

• Broken Segment : During Transcoding the Original files are broken into segments and while player tries to decode the segment ,faces Fatal error due to corrupt or missing data
• 404 On CDNs : This happens because of synchronization issue between Origin Server and Distrubutor[CDN]
• Malformed Manifest – Manifest files are text files and if any of the syntax is out of place ,the stream would break

Device Limitation 

Every device has Decoder which unpacks the video data .

Playback Errors which occur due to Hardware specific Codec incompatibilities or Decoder Crashes.

• Device Limited RAM : 4K stream or complex “High Profile” H.264 files need a lot of Memory for decompressing . IF the device is not having enough memory or RAM,the decoder will crash and it may reboot the device or crash the App
• CODEC incompatibilities : Codec is language in which the video is written in. There is can be a possibility that Codec standard used is not supported by the device itself on which the playback is initiated
• HardWare Decoder Limitation: There are dedicated chips (like in a Roku or a Smart TV). If the video wasn’t encoded exactly to that chip’s specifications,Video will not play

DESIGN STRATEGY AND MITIGATION TO HANDLE PLAYBACK ERROR

As a rule which building OTT Platform or while building a player following things should be considered and implemented

• Retry

  • Apply exponential Retry Mechanism when Segments are not getting  loaded

• Multi CDN Implementation

  • If One CDN is having latency or 500 series error then gracefully switch to other CDN .User should only notice a brief buffer

• Drop Stream Quality

  • If higher stream are failing drop to lower stream quality .For e.g. 4K stream due to Bandwidth constraint is failing then  gradually change the stream to 1080 then to 720 and so on

• ProActive Measures : Quality Check

  • Perform RPI [ Reachibility -Playability and Integrity] on Video Stream to ensure if the video streams are not broken

• Reactive Measures :

  • Collect Logs when the user is witnessing failures and perform analysis on following Metrics to identity the issues
    • Video Start Time Out Percentage – NO of users who dropped before first frame of content
    • Error Before Video Start:No of users who dropped during loader spinner
    • Video Start Failure :The percentage of playback attempts that fail to render the first frame of video after a user initiated content Playback

• Make Error User Friendly

  • In Case if user lands into an error state during  and no mitigation strategy works then  Make Error Codes and Description user friendly and Understandable  instead of giving technical Error codes and Errors
  • Also On the error screen always have CTAs for user engagement and action which keeps them engaged and user gives you another chance to initiate playback

VERDICT

Playback Error Handling is non glamorous functionality or feature which is a backbone of OTT Apps which should be treated as “MUST HAVE “ to give users a better Playback experience