Tackling the Practical Aspects of Baseband to IP Transition

Many broadcast equipment manufacturers describe their systems in terms of helping organisations migrate gradually to IP networking and connectivity, and how well a piece of equipment works in a hybrid IP/SDI environment. But broadcasters need to know what aspects of their systems will be the most critical during SDI-to-IP transition before they invest in new equipment, and understand the value of an incremental approach, economically and for workflows.

We spoke to Olivier Suard, Vice President of Marketing at Nevion, about the practical side of migration and hybrid networks. In 2018, research from Nevion found that over 40 percent of global broadcasters had already begun to move towards IP. As broadcasters migrate, because they have invested heavily in baseband systems for many years, most don’t usually see a business case for replacing everything, from monitors and cameras to switches, unless the equipment’s functionality actually needs to be upgraded.

Broadcast Business

Instead, in the interest of business viability, broadcasters are concentrating on building out an IP media network that will benefit them the most in terms of both cost-savings and workflow transformation. Olivier said, “In other words, broadcasters should transition from an all-baseband to an all-IP environment in an incremental manner, running a mixed environment where it makes sense to do so.

“Currently, even those broadcasters that have introduced some elements of IP in their network are likely to connect a mixture of SDI and IP equipment to it. Even in cases where broadcasters have moved facilities, most of the equipment is likely to remain based on SDI systems for quite some time.”

Baseband Islands, Connectivity and Routing

While SDI/IP adaption equipment makes an easy, convenient way to connect the SDI equipment to the IP core network, it may not always make sense, economically and from a workflow point of view, for all SDI equipment. If it ends up being used together within the confines of a studio or control room, the result is what Olivier calls a ‘baseband island’, where SDI signals are simply converted to IP and back again.

“Therefore, the most cost-effective way to distribute signals between baseband equipment, or signal processing such as audio embedding onto SDI signals or SDI frame synchronization, may just be to use baseband routing and other equipment rather than converting twice,” he said. “Keeping large Master Control Room (MCR) matrices may be going too far, however, and having to connect all the equipment centrally wouldn’t help solve the cabling headache.”

For that reason, the most cost-effective distribution and routing is likely to be compact SDI routers located within the baseband islands. Because they take on part of the job done by the MCR routers, they need to include a high level of redundancy and SDI processing capabilities. These baseband islands can then be connected to the rest of the IP network through adaption equipment.

Optical Links for IP Transport

“Traditionally, the transport of baseband signals beyond studios has been handled by fibre, with a dedicated interface onto and from the fibre,” said Olivier. “As the industry moves to IP, the requirement for high data-rate transport will continue to grow, with uncompressed HD requiring a minimum of 10GbE data rates. Fibre remains well-suited to transport signals for distances longer than a typical patch cable.”

Nevion Video IPath media network control and orchestration

Although IP can be transported over fibre, the conversion of baseband to optical links is still less expensive than baseband to IP conversions. This means that if equipment located far away is baseband, it can be cheaper to transport the signals through baseband electrical-to-optical (EO)  converters. As a result, according to Olivier, investment optical transport equipment continues to be relevant in today’s IP world and will be an investment in the transport network of the future – using fibre to transport IP as well as baseband.

Orchestration across SDI and IP systems

While adaption equipment can ensure that the SDI world is connected to the IP world, and vice versa, orchestrating and controlling the flows between the two environments is a crucial issue. Most media network management and control systems have been developed for SDI systems and cannot manage IP, and most IP network management systems don’t handle SDI. “The situation is particularly problematic for broadcasters who want or need to keep some form of SDI routing in the network, for example, within specific studios. It means looking out for a versatile orchestration and SDN (Software Defined Network) control system that can handle both environments,” Olivier said.

“Such systems will be able to give a complete view of the network and can control both IP and SDI routers, plus the adaption equipment and other appliances. As a result, this type of orchestration and SDN control system allows singular deterministic paths, from an input to an output, through a mixed SDI/IP network infrastructure which, in turn, makes it possible for broadcasters to set up a mixed SDI/IP environment that suits them best.”

In the end, with the right orchestration and SDN control systems, broadcasters don’t need to go to an all-IP network at once – they can choose equipment based on functionality and cost, not SDI or IP connectivity – and have the flexibility to make their transition to IP more cost-effective.

Production Staff and Broadcast Control

The broadcast operations need to be controlled as well, of course. Production staff are generally used to a specific broadcast control interface and reluctant to move away from it. However, like the orchestration software, typical broadcast control systems are not designed to control IP networks.

Production staff keep their existing methods, while the underlying network system evolves.

Olivier noted that the solution here is to make sure the broadcast control system can interface with the orchestration layer, which is usually done via APIs supplied by the broadcast control system and implemented in the orchestration system. A tight coupling of the familiar broadcast control systems and the orchestration layer means that production staff can maintain their existing method of working, even as the underlying network system evolves.

Greenfield – or Not

“Ultimately, only those broadcasters moving to new facilities and starting with a greenfield site have the luxury of building an all-IP network from scratch,” he said. “The majority of broadcasters will need to use hybrid SDI/IP systems. Sýn (Vodafone Iceland) is an illustration of how this set-up can work. It now operates with a core IP network, baseband islands and fibre transport.

“Fortunately, as demonstrated, it’s possible for broadcasters to transition from baseband to IP in an incremental manner and results in making the most from their existing SDI equipment as they start to see the cost-saving and workflow transformation benefits IP brings.”  nevion.com