Addressing the Challenges Posed by UDP Video Transport in ISR Workflows
Video technology plays a critical role in many defense and security operations – especially with Intelligence, Security, and Reconnaissance (ISR) applications. As the importance of video grows, the technology behind it has made leaps and bounds, for the most part. As much as there have been significant improvements to most video streaming technology, many defense and security workflows are still employing the same the same video transport protocol, TS over UDP, as they have for nearly 15 years.
What is UDP?
UDP is an acronym for User Datagram Protocol. It is a connectionless, high-performance data transfer protocol designed specifically for the high-volume transfer of large datasets over high-speed wide area networks (WAN). UDP became the preferred transport protocol in many government and security applications for a number of reasons, including its low latency, native carriage of KLV metadata, and one-way IP transport; this last point was especially important, considering the prominence of the Global Broadcast Service.
Challenges for UDP in ISR Applications
UDP was initially selected as the preferred video transport protocol in 2006; many things have changed since then. Compression algorithms, video streaming hardware, and sensors have all seen significant improvements over time. However, UDP still has several weaknesses that can severely compromise video quality.
One of the main weaknesses of UDP in ISR applications is that it is not a resilient transportation protocol. UDP was designed to be fast; it was not designed to perform well in anything less than ideal conditions. The protocol is especially vulnerable to jitter, (the variance in delay between data packets) as well as packet loss. This often creates choppiness and pixelation in the final image, which can adversely affect operations. And debugging these issues, or even isolating the cause, can be both complex and time-consuming.
SRT: A Modern Alternative
The Secure Reliable Transport (SRT) protocol was specifically designed to address the challenges of live low-latency video transmission over unpredictable networks; it needed to be fast, like UDP, but also reliable, and secure. It accomplishes this through the implementation of transport-layer mechanisms which enable packet-loss recovery and signal-timing reconstruction.
SRT addresses the main challenges associated with UDP as a transport protocol for ISR applications in regards to video quality, and has shown a number of other advantages. It keeps streams secure with AES encryption, easily traverses firewalls, controls latency, and is supported by several tools critical to security and defense applications, including VideoLAN’s VLC, FFmpeg, GStreamer, and Wireshark.