How broadcasters can make an incremental move to an all-IP environment

Processing and connectivity

The move to IP is largely focused on the network, rather than the production equipment: broadcasters most commonly are or envisage using a mixture of SDI and IP equipment connected to an all-IP network. Adaption equipment is normally used to connect the SDI equipment to the IP core network. That said, connecting a lot of SDI equipment to an IP network may work out to be quite expensive. Furthermore, 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 and using baseband routing technology may be the most cost-effective way to distribute signals.

Similarly, signal processing, such as audio embedding onto SDI signals or SDI frame synchronization, may be best done directly in a baseband environment rather than converting to IP, processing and converting back to baseband. Some may argue that broadcasters should, therefore, keep the existing large Master Control Room (MCR) matrices to handle this. This, however, is likely to be overkill in many cases. Also, if all the equipment needs to be connected centrally, it doesn’t help solve the cabling headache.

Consequently, the most cost-effective distribution and routing for such islands 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.

The use of fiber technology

The transport of baseband signals beyond studios has traditionally been handled by fiber, with technology providing the interface onto and from the fiber. 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. Fiber remains ideally suited to transport signals any distance longer than a typical patch cable.

While IP is transported over fiber, the conversion of baseband to optical links is still a less costly solution than baseband to IP conversions. Hence, if equipment located far away is baseband, it can be a more cost-efficient solution to transport the signals through baseband EO converters. As a result, optical transport technology will continue to be relevant in an IP world and any investment in that technology for the transport of signals today is an investment in the transport network of the future – using fiber to transport IP as well as baseband.

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. Most media network management and control systems have been developed for SDI technology and cannot manage IP. Conversely, IP network management systems don’t handle SDI. This is particularly problematic where the preferred option of a broadcaster is to keep some form of SDI routing in the network, for example, within specific studios. This calls for 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. Therefore, this type of orchestration and SDN control system can provide deterministic paths through a mixed SDI/IP network infrastructure, which makes it possible for broadcasters to have the mixed SDI/IP environment most suitable for them.

In other words, with the right orchestration and SDN control systems, broadcasters don’t need to move to an all-IP network at once. Instead, broadcasters can choose equipment based on functionality and cost, rather than SDI or IP connectivity and gain greater flexibility which makes for a more cost-effective transition to IP.

Broadcast control systems

Production staff are typically used to a specific broadcast control interface and are often reluctant to move away from it. However, 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.