Low Latency Solutions was one of the key concepts of 2019, and it’s no less important in 2020. In this buyers’ guide,Streaming Media’s Jan Ozer discusses how to determine what kind of latency you need as well as identify the available technologies and detail factors to consider when choosing among them.
Most low-latency solutions use one of three technologies: WebRTC (Real-Time Communications), HTTP Adaptive Streaming, or WebSockets. As the name suggests, WebRTC is a protocol for delivering live streams to each viewer, either peer to peer or server to peer. It was formulated for browser-to-browser communications and is supported by all major desktop browsers on Android, iOS, Chrome OS, Firefox OS, Tizen 3.0, and BlackBerry 10, so WebRTC-based low-latency solutions should run without downloads on any of these platforms.
WebRTC is typically the engine for an integrated package that includes the encoder, player, and delivery infrastructure. Examples of WebRTC-based solutions are Real-Time from Phenix, Limelight Realtime Streaming, and Millicast from CoSMo Software (see https://cosmosoftware.io/products/). You can also access WebRTC technology to build your own solution in tools like the Wowza Streaming Engine, CoSMo Software, and Red5 Pro Server. Latency times for technologies in this class include a global guarantee for delivery to all viewers in under 500 milliseconds (Phenix), delivery in under 500 milliseconds (Red5 Pro), and under 1 second (Limelight Networks). Time to First Frame (TTFF) is also an important metric where technologies such as Phenix deliver TTFF of < 500ms for 71% of viewers and < 816ms second for 90% of viewers. If you need sub-2-second latency, WebRTC is an option you should consider.
If you have an application that requires much lower latency, you’ll probably need a WebRTC-based or WebSockets-based solution or a proprietary HTTP technology. In either case, asking questions in the article linked to this News item should help you identify the technology and/or service provider that best meets your needs.