As part of a proof of concept for the worldwide transmission of HD-SDI video signals in the form of SRT streams, a signal runtime of less than half a second was achieved between Hamburg and Tokyo.
The background to this renewed trial was an acceptance test of the SRT application in cooperation with manufacturers and partners of MCI.
This “worldwide” pilot project was the logical continuation of a series of tests and measurements by the MCI Solutions Team, which began in autumn 2020 with Germany-wide SRT long-distance tests. MCI, together with partners Haivision and GlobalM, provided live switchboard talks and live video feeds with the NDR-operated ARD studio in Tokyo. The basis for this was provided by the cloud-based streaming services Haivision Hub on Microsoft Azure and the GlobalM network on AWS.
The aim was to show that it is possible today to carry out streams in SNG transmission quality, provided that the signal runtimes are the same or considerably shorter. Transmission in 12G via quad-link input in SRT encoders could also be realised.
At MCI’s XMediaDock in Hamburg, the camera signal was encoded and sent to Tokyo in the form of an SRT stream. There, the signal was HD-SDI converted back and then also transmitted via SRT stream from Tokyo back to Hamburg. Here, the latency of the signal runtime “Hamburg – Tokyo – Hamburg” was 24 frames, i.e. 960 ms.
Lasse Bickelmann, MCI Solutions Engineer:
“Transmitting SRT streams over the public Internet is much more cost-effective than using a dedicated line or satellite link for this purpose. By using content delivery networks for SRT streams, locations around the world can be linked together in sub-second 4:2:2 10-bit picture quality. Here, SRT transmissions require little configuration effort and are quickly established.”
The transmission security of SRT streams can be further increased by using the dual-path mode. In this case, the SRT stream is sent via two different routes at the same time. The data packets that arrive first at the recipient are used.
In recent years, MCI has realised numerous online and streaming productions. The difficulty has always been to transport the signals in high resolution and securely over the web. Therefore, the expansion to include IP long-haul networks was a necessary and timely step, which was made possible by the cooperative collaboration with the NDR.
“Now we are in a position to network the most diverse locations worldwide with low latency in SNG quality in a short time…”, concludes Lasse Bickelmann.