The future of broadcasting is in IP. But how can broadcasters make a smooth and cost effective transition without disrupting workflows?
More and more broadcasters are looking to migrate production from the traditional baseband infrastructure to an IP solution in order to meet the growing pressure of providing additional content and channels with even fewer resources. The decision to move to IP should be fairly straight forward, based on the obvious benefits of operating in an environment that is extremely flexible and cost-effective.
The technical reservations regarding the technology, including reliability, latency, management and support for key functionality like effective clean-switching, can all be overcome with the right, standards-based equipment and software. However, even when the decision to move to IP makes sense, there still remains the question of how can this be done cost-effectively without having to scrap existing baseband investments or getting locked into a proprietary solution.
And it really works! Recently, the EBU and VRT launched the LiveIP project to create a fully IP studio, using at the core an IP network based on standards (Openflow, SMPTE 2022-6, AES67).
A careful approach to migration
The broadcasters’ production environment has been built over many years, and contains a vast amount of expensive networked equipment, including cameras, switchers, mixers, monitors, etc. Commercially, it makes no sense for broadcasters to scrap all of their baseband investments and replace them overnight with IP.
The common sense approach is for broadcasters to move to IP incrementally, as their business needs evolve, and to make the transition as simple and straight forward as possible.
There are three core principles that need to be considered when it comes to introducing IP in the facilities. The first is to make allowances for a period of co-existence between baseband and IP which may stretch over a few months or last for years. The second is adherence to recognised standards the benefits of IP cannot be realised through proprietary approaches. The third and final principle is that the architecture should be based on the use of Software Defined Networks.
The right architecture
One concern of broadcasters moving to IP is that the distributed-nature of typical IP networks appears to be very different from the familiar centralised architecture currently used in facilities. This makes it very tempting to opt for solutions that are not fully IP compliant, but look and work like existing networks. This is obviously counter to the principle of moving to open, recognised industry standards to get the full benefits of IP.
As it happens, the architecture of modern, robust networks, as used for example by telcos and data-centres, is not in fact that dissimilar conceptually to that of baseband networks. It is based on a leaf-spine set-up. The equivalent of the central router in the MCR is the spine – a set of standard IP routers. The spine routers are connected to leaf networks situated in various locations, eg in this case the studio. The leaves consist of standard IP routers combined with gateways that provide the bridge between baseband technology and IP. Each leaf is connected to multiple spine routers, thereby ensuring reliability and scalability, with bi-directional links. The gateways also add an extra layer of reliability, with protection mechanisms that ensure signals are never disrupted. The spine-leaf architecture scales easily by simply adding new routers to the spine, meaning that in theory, there’s no limit to the size of the network. Furthermore, the growth is incremental no need to scrap a router to buy a bigger one, simply add another router to the existing one.
The whole network is controlled by management software, making it a software defined network (SDN). The management software defines the routes between the sources and destinations to ensure the right level of deterministic performance. The management software can also ensure clean-switching at IP level something that can be achieved, with the right technology, on any standards-compliant IP router with the right speed and without double signal transport.
As the network is IP based, handing signals over to other networks such as remote production, telco networks or other broadcasters, is a standard IP feature. Any router in the network can forward the packets to any other connected network, even if the latter is not SDN-based. Broadcasters do not need any specialist gateways or bridges to achieve this. Remote locations effectively become extensions of the central studio/campus, with an IP contribution network sitting between the spine and the remote leaf.
The gateways provide a way to make the new IP architecture work alongside a baseband network and equipment. With this architecture broadcasters can have their new IP network running alongside, and indeed be co-located with, their existing baseband network. Studios and equipment that are baseband-based can simply be connected to the network via the gateways, which act as a bridge between baseband and IP.
Traditionally, the broadcast sector has focused its investments on wholesale equipment replacement. This was perhaps more efficient during the decades where we saw little change in the industry. However, in recent years the rapid evolvement in video and audio standards, from SD to HD and now 4K and beyond, has brought greater need for flexibility and speed. IP networks are designed to carry any data that can be converted into IP packets, and they can evolve alongside advancements in other broadcast technology, eliminating the need for wholesale replacements.
Leaf-spine architecture enables broadcasters to start with a very simple network, with relatively small routers, and extend it as and when the need arises. When extra capacity is needed in an IP network, for example to handle higher definition or frame rates, new routers can simply be added. As mentioned before, existing routers don’t need to be scrapped. This represents a substantial saving, as the life-time of the router can be extended, and the incremental investment will be significantly less than a wholesale replacement.
Managing the system
The key to efficient management of the transition from baseband to IP is to ensure that the migration of the network is transparent to those who need to manage it. There is a growing need for a media service management system capable of handling baseband and IP networks that presents a broadcast-centric view of the network as a whole. Operators will then have peace of mind, as all the complexities of network transitions will be hidden to allow the workflows to remain undisrupted.
The move to IP does not need to be a challenge for broadcasters and given the right management system, an IP and baseband network can actually improve workflow. It will ease the uncertainty during migration, and ease the pressure on broadcasters to oust their baseband investments.
By Olivier Suard, marketing director, Nevion