At IBC 2013, we demonstrated the first early preview of a new network protocol called SRT in the HaiGear corner at our Haivision booth. While HaiGear demos are always very forward looking and often just proof of concept or design ideas, this one went a long way.
Doing live interview filming in a hotel suite outside the IBC complex, we transmitted the live streams over the public internet onto the show floor, displaying it on a TV at our booth. In order to achieve this under extremely challenging network conditions with over 5% packet loss, we combined our brand new network protocol SRT with the not even yet standardized HEVC video codec. Combining both technologies proved to be the perfect combination to get around first mile issues under extreme conditions often faced in live event productions.
Coming from a protected network world and typically utilizing the UDP protocol for lowest latency transmission of high quality video over local area networks, Haivision’s move to multi-site enterprise installations required a new solution to take care of packet loss, jitter, delay and security when trying to send those streams from one site to another one over the public internet.
SRT – Secure Reliable Transport – is a Reliable UDP based and completely content agnostic network protocol for low latency audio, video and general data transmission over unreliable networks such as the public internet. It recovers packet loss up to very high rates, encrypts the stream with standard AES 256 (or 128) and carries real-time behaviour from the sender to the receiver, which is extremely important when streaming variable bitrate streams, as often used for video transmission.
SRT is implemented as low level C/C++ library, builds on Windows, Mac OS X and Linux, has a very low footprint and can therefore be used on a wide range of platforms, including embedded devices, mobiles phones as well as workstations or servers.
At NAB 2017, we announced the SRT Alliance, initiated by Haivision and our friends from Wowza with the goal to thrive the adaption of the protocol, get the attention of the Open Source community and utilize the creative energy of talented developers out there.
The amazing feedback we received from the industry during the show surpassed our expectations and is super exciting to everyone involved 🙂 What a ride so far!