What challenges and benefits exist within a Remote Statistical Multiplexing broadcast system?

Does remote statistical multiplexing bring benefits to all parties involved in the broadcast transmission chain?

Remote Statistical Multiplexing provides a smarter and more efficient way of working.

In this blog we’re going to briefly examine some of the key challenges and benefits that exist within a Remote Statistical Multiplexing (RSM) broadcast ecosystem. A tough ask when working within a 500 parameter, but we’ve given it a go…

Modern digital broadcast head-ends can maximise efficiency from a fixed and limited capacity, albeit a satellite, cable or terrestrial network, through a method known as Statistical Multiplexing. During this process, video sequences within each stream on a multiplex are exploited, in real-time, to help maximise utilisation compared to Constant Bit Rate (CBR) encoding. Critically, picture quality is maintained throughout this whole process. In layman’s terms the most demanding video sequences are able to ‘borrow’ capacity from less vigorous streams. RSM is a variation of this technique; the difference being that head-ends instead rely on high-speed IP networks to distribute the system over a wide area.

Although more sophisticated, does the technique bring benefits to all parties involved in the broadcast transmission chain?

Broadcasters with multiple distributed playout facilities incur significant costs when aggregating video streams to a single shared encoding and multiplex facility. Using a distributed architecture, video is compressed only once, and at source, therefore equipment and connectivity bandwidth can be significantly decreased leading to a reduction in the total cost of ownership.

Because a video stream shares capacity with all other streams within the same pool of bandwidth, you’d be forgiven for thinking this may have a detrimental effect on picture quality. With the appropriate configuration, and elimination of concatenated encoding hops, the end result can be quite the opposite. Updated encoding algorithms and low latency networks have led to no subjective reduction in the quality of the video whether encoders are local to or remote from the multiplexer. The end user will therefore experience an improved picture quality.

RSM has many notable commercial advantages, but an increase in flexibility and agility should not be underplayed within such a dynamic industry. By using IP technology we are able to rapidly re-define and re-configure system topologies and multiplex bouquets without the need for expensive physical re-engineering or timely circuit provisioning.  This flexibility brings options for service continuity and disaster recovery not easily achieved through traditional technologies and architectures.

Another important consideration is the potential space and power savings. RSM technology requires a relatively small amount of physical space when compared to more traditional technology types; helping reduce both fixed and variable costs.

With any demanding application it is critical to understand the behaviour of both the network infrastructure and edge devices to ensure they work together in harmony.  A secure, predictable and reliable underlying network is essential for error free operation and getting this right requires specific knowledge, skills and experience. Resource like this is not always readily available and may require outsourcing. The D3&4 multiplex expertly demonstrates how this can work.

Whether you’re a capacity manager, individual channel or major broadcaster there are numerous commercial and functional benefits from employing RSM technology. It is clear this technique provides a smarter and more efficient way of working.

As the industry is now adopting and realising the benefits of this technology, can this move us towards a fully software defined transmission chain? 

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