Resilient Streaming Protocol (RSP)
The Smartest Way to Deliver Your Content
The Resilient Streaming Protocol (RSP) is the first live streaming technology that fully protects against audio and video quality loss during transmission regardless of network interruptions. It is intended to be used in any application which requires that live multimedia be free of imperfections caused by transmission problems and where the viewing experience cannot be interrupted by missing or lost content. Because RSP guarantees complete and error-free audio and video delivery, it can confidently be used for live streaming over unpredictable networks such as wireless cellular hotspots.
Error-Free, Perfect Quality – FEC vs. RSP
Streaming live video over unpredictable networks (like the Internet) has historically always been a problem. Before RSP, the most effective live streaming technologies have used Forward Error Correction (FEC) techniques which send a limited amount of redundant data to hopefully protect against loss of content during transmission.
With FEC, only a limited amount of redundant data is sent, and if all of the data for a particular section of video is lost (which is likely to happen eventually on an unpredictable network) that video content is lost for good, resulting in pixelated images, complete gaps in content, or even total playback failure.
Unlike FEC, RSP uses a combination of selective retransmission and data verification checks to ensure that all data is received perfectly by the destination. In doing so, RSP assures that the destination receives an exact copy of what was produced by the live streaming encoder. If the data received by the destination is not a perfect copy, RSP re-transmits only the data that was corrupted during transmission.
Transcoding and VOD from “Source”
Because other streaming protocols such as RTMP and any of those that use FEC techniques (MPEG-TS, Zixi, SRT, etc.) all have the potential to lose video data while en route to a cloud server, streaming with any of these protocols over an unpredictable network is likely to result in the cloud server having incomplete video data for media processing and distribution. For example, if a cloud transcoding server is receiving a single 1080p video via an FEC-based protocol and some of the video content is lost in transmission due to excessive packet loss, each transcoded video rendition produced by the transcoding server will contain the same video errors as the imperfect source 1080p version. In this case, live viewers will see the problem(s) with the video no matter which resolution/bitrate version they are watching. Additionally, the entire video will have to be replaced with a non-corrupt version after the live event has ended if the same content is desired to be used for video-on-demand (VOD).
In contrast, broadcasters who use RSP for streaming live video to an RSP compatible cloud transcoder (such as the transcoder which powers Living As One’s Web Platform) can be certain that their multi-bitrate video has been created from a perfect and complete audio/video source. Another major benefit of streaming with RSP and an RSP cloud transcoder is that unlike with RTMP or FEC protocols, an RSP cloud transcoder is not limited by a certain amount of time in receiving the audio/video data. If an RSP live streaming encoder temporarily loses network connectivity and cannot send audio/video, the RSP cloud transcoder simply waits for the network to be restored. Whenever the encoder’s network is restored, the encoder transmits all data which has not been received by the cloud transcoder, and the cloud transcoder resumes transcoding from exactly where it left off. This ensures that live viewers will have a gapless and error-free adaptive bitrate viewing experience even in the case of high packet loss or total transmission interruption during the live broadcast. Videos streamed with RSP can also be immediately made available for VOD because they were transcoded and stored from a perfect and complete source, so there are no video errors that need to be corrected after the live event.
When broadcasters are considering streaming from networks which they have not evaluated or do not control (such as a network provided by a rented venue), they will often have concerns with continuous internet connectivity, upload bandwidth availability, and firewalls blocking access to streaming. Fortunately, RSP natively addresses each of these problems.
Since RSP is designed to protect against audio/video loss during connectivity problems, broadcasters can be at ease knowing that their video will not be affected by temporary connectivity outages or bottlenecks in upload. This protection is so extensive that RSP even supports switching networks, such as moving from one cellular carrier to another mid-stream, all without losing data. Additionally, encoders using RSP can leverage multiple internet connections simultaneously through multi-WAN load balancing without any extra configuration. These additional networks can be in place as a backup or to provide additional upload bandwidth.
RSP also uses the standard internet ports 80 and 443 to upload live video and the same ports to receive feedback from the destination which means no firewall modifications are needed at any location. This simplifies streaming setup and also protects against content filtering devices designed to block streaming appliances which use non-standard internet ports.
Learn More About RSP
Contact us to see how RSP can provide highly resilient audio and video transmission for your specific application.