• New – Websockets decoupled from streams (allows shared objects to be used independently of a live stream)
• New – Stream encryption via SRTP for mobile SDK clients (NOTE: Requires Red5 Pro Mobile SDK version 5.5.0 or higher)
• New – Unpublish stream server API call unpublishLiveStream
• Clustering – streaming on demand is active by default
  • NOTE: if you want to play back HLS over cluster/autoscaling, then you will need to change streaming on demand to false in {red5pro}/conf/cluster.xml
• Fixed – Invalid response trying to get stream stats for a subscope
• Fixed – Errors if two separate clients attempted to subscribe to a stream at the exact same time
• Fixed – Conference example leaves one connection on hold or closes connections
• Fixed – Chrome WebRTC broadcaster bitrate doesn’t go above 600 kbps (fixed in HTML5 SDK)
• Fixed – AWS Cloud Storage Plugin may list out wrong folder if you have multiple root folders
• Fixed – Firefox WebRTC to Safari HLS stalls after around 2 minutes (note: fix requires enabling preprocessor in the webapp, which will also increase CPU usage)
• Fixed – Autoscaling – Error reading a configuration policy that contains the 0 character
• Autoscaling – Improved error messaging when trying to add origin node to a VPC that doesn’t exist

Release 5.5.0 Server Performance Metrics

Tests were run against an AWS c5.large instance (2 CPUs with 4GB memory, 2GB allocated to java_heap). We used our RTMP Bee, RTSP Bee, and RTC Bee clients to do load testing.

Publishing a 240p (426×240, 256kbps) stream via RTMP, we were able to achieve the following while still maintaining quality of stream:

• 500 WebRTC subscribers

• 2,000 RTSP (mobile) subscribers

• 1,100 RTMP subscribers

• Publishing a 720p (1280×720) 1,500kbps stream via RTMP, we were able to achieve the following while still maintaining quality of stream:

• 220 WebRTC subscribers

• 450 RTSP subscribers

• 300 RTMP subscribers

The same server type (2 CPUs with 4GB memory, 2GB allocated to java_heap) can support approximately fifty 480p RTMP publishers (tested using the RTMP Bee Publisher test).