IP has become an increasingly attractive option for broadcasters, allowing them to cost-effectively do more with less and offering a greater degree of flexibility. As such, we are seeing a growing number of broadcasters making the move to IP, with research from Nevion finding that in 2018, 40% of global broadcasters had already begun to transition towards IP. While moving to IP is undoubtedly beneficial, it is vital that broadcasters consider several factors before beginning the transition.
Connectivity and processing
Currently no broadcasters are operating in an all-IP environment. Instead, they are likely to be using a mixture of SDI and IP equipment connected to an all-IP network. While SDI/IP adaption equipment can be used to connect the SDI equipment to the IP core network, connecting a lot of this equipment to an IP network can be expensive. Plus, it might not be necessary, as that equipment will often be used together within the confines of a studio or control room. In these “baseband islands”, converting SDI signals to IP and back to SDI may be superfluous.
As a result, the most cost-effective way to distribute signals between baseband equipment could be to use baseband routing technology. Similarly, signal processing, such as audio embedding onto SDI signals or SDI frame synchronisation, may be best done directly on baseband equipment rather than converting to IP, processing and converting back to baseband. Some would argue that broadcasters should keep the existing large Master Control Room (MCR) matrices to handle this. However, this is likely to be overkill in many cases.
Consequently, the most cost-effective distribution and routing is likely to be compact SDI routers located within the baseband islands. As these routers take on part of the job done by the MCR routers, they also need to offer a high level of redundancy and include SDI processing capabilities. These baseband islands can then be connected to the rest of the IP network through adaption equipment.
High data-rate transporting
Traditionally, the transport of baseband signals beyond studios has been handled by fibre with technology providing the interface onto and from the fibre. As the industry moves to IP, the requirement for high data-rate transporting will continue to grow – with uncompressed HD requiring a minimum of 10GbE data rates. Fibre remains ideally suited to transport signals any distance longer than a typical patch cable.
While IP is transported over fibre, the conversion of baseband to optical links is still a less costly solution than baseband to IP conversions. Therefore, if equipment located far away is baseband, it can be a more cost-efficient solution to transport the signals through baseband EO converters. Thus, optical transport technology will continue to be relevant in an IP world and any investment in technology for the transport of signals today is an investment in the transport network of the future.
Orchestrating and controlling flows in mixed environments
While adaption equipment can ensure that the SDI world is connected to the IP world, and vice versa, a crucial issue is how to orchestrate and control flows between the two environments. This is significant as most media network management and control systems have been designed for SDI technology and can’t manage IP. Equally, IP network management systems don’t handle SDI. This is particularly problematic when broadcasters prefer, for example, to keep some form of SDI routing in the network within specific studios. This requires broadcasters to implement a versatile orchestration and SDN (Software Defined Network) control system that can handle both SDI and IP environments.
These systems hold a complete view of the network and can control both IP and SDI routers, as well as adaption equipment and other appliances. As a result, this type of orchestration and SDN control system can provide deterministic paths through a mixed SDI/IP network infrastructure and makes it possible for broadcasters to have the mixed SDI/IP environment that works best for them. Basically, with the right orchestration and SDN control systems, broadcasters don’t need to move to an all-IP network at once. Instead, it’s possible to choose equipment based on functionality and cost, rather than SDI or IP connectivity. With the flexibility this offers, broadcasters can transition to IP in a more cost-effective manner.
More often than not, production staff are used to a specific broadcast control interface and tend to be reluctant to move away from it. Yet, popular broadcast control systems are not designed to control IP networks. The solution is to ensure that the broadcast control system can interface with the orchestration layer which is typically done via APIs provided by the broadcast control system and implemented in the orchestration system.
A tight coupling of the familiar broadcast control systems and the orchestration layer ensures that production staff can maintain their existing method of working, even as the underlying network technology evolves.
Seamless migration to IP
In reality, it’s only broadcasters who are moving to new facilities and starting with a “greenfield” site that have the luxury of building an all-IP network from scratch. The more common scenario will be broadcasters using IP to build out capacity or to add new IP studios or control rooms, and needing to maintain their core SDI network, for both practical and financial reasons.
Fortunately, moving from baseband to IP needn’t be an all-or-nothing decision for broadcasters. Instead, it can be done incrementally so as to keep costs down, continue using existing equipment that has no real need to be replaced and to ensure production isn’t impacted, with adaption equipment and orchestration key to ensuring a smooth and seamless transition to IP.