SCREEN AFRICA EXCLUSIVE:
Written by Peter Walker, Senior Product Manager at Calrec
As IP connectivity becomes more accessible to all sectors of our industry, those with their sights set on interoperability are working harder than ever to play well together. AES67 defines a common language for the streaming of live, high-quality, low-latency audio over IP, and its adoption by ST2110 secures its place as the way forward for audio over IP in broadcast.
But what can broadcasters do to manage the transition from traditional connectivity, and how do they achieve the full benefits that have been promised with IP workflows?
In reality, many broadcasters are unable to commit to a full-scale shift. There are a number of reasons for this. Moving to a completely new system is not only financially draining but it also has a learning curve. This curve is steep; there is much to learn within even a modest broadcast facility to go full IP.
For this reason, many broadcast manufacturers offer IP interfaces that allow their equipment to be connected to an IP network, while maintaining other more familiar interfacing options. This allows broadcasters to migrate over time as and when they purchase new equipment allowing time to bed-in and expand within their comfort.
Using a gateway technology allows users to start leveraging the advantages of IP with a much softer learning curve. Not swapping out all the equipment simultaneously means current systems can continue to be used, keeping everything on air and allowing the transfer to be non-disruptive to the programming schedule. It allows the broadcaster to get the full value out of their investment.
And, once a gateway has been introduced and an IP network established, broadcasters can start introducing other equipment onto the network, either with native IP equipment or via other gateways. Gateways allow broadcasters to transition to full IP infrastructures in their own time.
They also ensure that the benefits of some proprietary systems, like Calrec’s deterministic and self-discovering Hydra2 network, can still be utilised. This can be very useful, for while there are many positives switching to an IP infrastructure, there is still work to be done to achieve truly dynamic connectivity within the network.
The positives are clear: one of the key advantages of moving to IP is the ability to use existing network infrastructures and COTS (Commercial-Off-The-Shelf) hardware. Broadcasters want to be able to pass audio, video, control and other data over shared IP networks, and they want to use open standards to exchange media between devices made by different manufacturers. Standardised IP connectivity eradicates much of the cost, space, system complexity and cabling overhead of having a multitude of interfaces for analogue, AES3, MADI, SDI, etc. This is the goal of both AES67 and ST2110.
AoIP has been around for many years, with lots of broadcasters already relying on it daily to produce live on-air content, but it has tended to be separate single vendor systems and/or relatively small networks. Even with Dante, the hardware and software of the IP connection is produced by a single manufacturer. AES67 and ST2110 allow for much larger, truly multi-vendor networks that can replace the whole connectivity backbone of a facility, with a much wider range of devices that can be used, preventing customers getting tied in to new purchase based on previous investment
AES67 gives us a standardised protocol and parameter set so that a device from manufacturer X can exchange audio streams with a device from manufacturer Y, but it’s still not necessarily simple to connect stream connections between different vendors. Doing so typically requires an engineer to configure output streams on each device and often manually enter complex configuration details in order to be able to receive streams from other devices.
While this works reliably, it relies on engineers to set up and it results in a static streaming configuration. For dynamic routing of audio, providing the operational workflows needed for live broadcast, we’re still relying on expensive broadcast routers, albeit via IP. This is not the goal of using COTS IP.
With AES3, you plug in a BNC, and the receiving device knows it is expecting audio on that connection. With AoIP, a single connection to a network allows for the exchange of many channels of audio with many different pieces of equipment, but they can only receive that audio if they know it exists in the first place. The fundamental part missing from both AES67 and ST-2110 is advertisement and connection management.
In the absence of an agreed standard many vendors followed the Ravenna approach, which is helpful for advertising AoIP streams between those vendors, but still leaves us with labour-intensive configuration in the UI of each device, resulting in static streaming connections.
This is where AIMS and the JT-NM are making progress. They are promoting NMOS, a standardised mechanism for not only discovery/advertisement (NMOS IS-04), but also connection management (NMOS IS-05). This means you do not have to log in to each device on a network to configure its connections, they can be managed from a central UI providing familiar broadcast workflows and using the network to perform the routing. NMOS has gained strong buy-in across the industry, from both manufacturers and broadcasters. It’s widely seen as the route to true interoperability, but its uptake has been slow in some areas.
As broadcast equipment manufacturers, true interoperability could be perceived as a threat because it increases competition, but we must protect our market share by making reliable, high-performing and easy-to-use products with feature sets designed for live broadcast applications, rather than by tying customers to proprietary systems.
To unlock the full potential of IP and give broadcasters the workflows, costs and efficiency savings they need to compete in the modern broadcast era, we must all work together to provide proven multi-vendor systems that are easy for operational staff to use. At Calrec we are working with our partners and following the JT-NM roadmap, working towards the ultimate goal of making life better for our customers.
Calrec is represented by Tru-Fi Electronics S.A. (PTY) Ltd in South Africa.