The AoIP technology has come of age, and we wouldn’t be surprised if it becomes a standard practice for audio broadcast, in the M&E space
By ANISHA GAKHAR
Just when the M&E industry was getting accustomed to the use of IP technology across most broadcast domains, AoIP made a red-carpet entry. AoIP stands for Audio-over-IP, which means distribution of digital audio across an IP network. It is being embraced extensively, to enable an improved quality of audio feeds over long distances. The technology is also sometimes known as audio contribution over IP (ACIP).
This enhancement typically comes in handy, when production has to be executed away from the home studios, in remote locations. The set-up calls for a reliable communication network, which can connect varied locations and hold them in tandem throughout the entire broadcast. Should the on-air talent move out of the TV frame, or need a new segment of audio or add-in be incorporated, AoIP makes it feasible to multi-task. For example, the crew might want to hear the on-air program and the producer’s comments, together, to ensure that the show runs seamlessly. The technology facilitates a smooth audio experience, irrespective of inter-mixing of noise signals, call-ins or external distractions.
THE CURRENT DRIFT
Most of the industries using AoIP are gravitating towards the AES67 technical standard, which is a layer 3 protocol suite, and allows interoperability between various IP-based audio networking systems.
According to Brian Ford, product line manager, Imagine Communications, the company uses the agreed standard, the AES67, which is the audio component of the SMPTE ST 2110-30 standard, for their AoIP needs. This solution is suited for both, industry vendors and users. When asked about Imagine’s shift to AoIP, Ford said,” At Imagine Communications, we are 100% aligned behind standards-based solutions for moving towards an IP infrastructure. Early adopters of uncompressed-over-IP relied on SMPTE ST 2022. The addition of ST 2110 gives us the same capabilities, or perhaps more, than that in SDI, which is routable audio in a production environment.”
As the smartphone gains importance as a general purpose input/output device, technology that connects the worlds with it, gain centre stage too. People with a VoIP SIP based phone system tend to look for solutions that have a one button dial environment. Reto Brader, VP- Sales and Marketing, Barix, said, “Barix’s AudioPoint 3.0 enables streaming on the smartphone, and can be used to support hearing-impaired, stream live translation to listeners, or to give a voice to the screen, for example, in the hotel lobby.
The Internet is also being used as a primary link for radio broadcast contribution and STL link technology. Thanks to redundancy solutions, this now is a viable solution that meets quality requirements. Bandwidth has become less of a limiting factor, and more PCM signals are sent over the Internet, instead of compressed streams. “Adding redundancy becomes easy with our Barix Redudnix solution, making the Internet a path for primary studio-to-transmitter linking,” added Brader.
Service providers offer clients to shift their encoding/transcoding functions to the cloud. This helps the broadcaster to save effort maintaining operating systems and software versions of its encoding platform. StreamGuys uses PCM digitisers to bring audio into the cloud, and process it according to the customer’s whims.
GatesAir, a provider of wireless, over-the-air content delivery solutions for radio and TV broadcasters, also seconds the benefits of using AES67 for their implementations. “AES67and the related control standards have been gaining significant attention over the last few years. Open standard protocols are enabling broadcasters to build their ecosystems using ‘best of breed’ equipment from different vendors,” said Keyur Parikh, VP and GM, GatesAir.
SMELLING THE WHIFF
How do broadcasters smell what’s new? From where does a first-timer collect information to ensure a flawless execution?
Industry experts rely on publications from standard bodies such as the European broadcasting Union (EBU) and Audio Engineering Society (AES). These standards bodies have working groups comprised of seasoned broadcasters and vendors, who look at new standards that are based on latest technologies to advance the state of broadcast networks.
It is also crucial for a broadcasting organisation to get closely involved in their peer community. Imagine Communications was one of the instigators of the AIMS project, with their representations in standards bodies like SMPTE and VSF. Participating in the various IP showcases at international conventions and events like the annual NAB show at Las Vegas and IBC at Amsterdam; gives great insights into what’s trending.
End-to-end IP transport has become a key goal for broadcasters worldwide, aimed at reducing their operational costs, along with increasing connectivity. Within the studio environment, AES67 has a noteworthy foothold. AoIP over WAN, however has challenges with regard to both, security and reliability. This in turn needs to be handled by the codec devices.
Again, by adhering to standards, broadcasters can ensure a foolproof network base. By focusing on standards-based architectures, broadcasters can aim at getting an infrastructure fully devised by IP technology, along with enjoying features of SDI and more, over low costs.
It is pivotal to start out with ‘off-the-shelf’ switches and products with standards-based interfaces, which offer interoperability. Choosing the right vendor, whose solutions resonate with the company’s exact requirements, in the initial stages of planning a transition to AoIP, is imperative to build a robust and brawny infrastructure. And a strong foundation spells confidence, to get to where you need to go.
The move to Audio-over-IP is merely one part of a bigger change in broadcast infrastructures. It is not a plain sailing task, to identify the audio portion of a much larger system. The transition to IP and virtualisation changes the way one perceives broadcast technologies. What essentially used to be one whole device, transcends to being something as facilitated as a software key with AoIP, running just when it is needed. AoIP has enabled the integration of broadcast with IT networks. This has simplified cabling, increased connectivity, and reduced operational costs by using commodity networking equipment.
AN EXPLICIT EXPERIENCE
Moving to an IP infrastructure with a standardised system, in turn makes design and commissioning of the set-up, an undemanding experience. Consumers get to savour better content, by virtue of media companies being able to spin up channels in a matter of days, thanks to IP workflows. It also means broadcasters can add pop-up channels as and when the need arises.
AoIP provides alternative routes to create content, for instance, sports stadiums curating their own services. On the production side, AoIP, over 4G/LTE and Wi-Fi are gaining importance. Service providers help tailor their offerings to professional users. “I personally believe that soon we will see radio streaming in cars over a standard IP smartphone connection,” said Brader.
Parikh commented, “Integration of AoIP into our GatesAir facility has allowed providers to leverage their IT infrastructure and knowledge base, significantly. This has enabled a widespread connectivity for terrestrial and web distribution, thus, making international content accessible to consumers across the globe.”
INNOVATING THE WAY AHEAD
Integration of reliability and security capabilities within IP Link codecs, has enabled broadcasters to leverage low-cost ISPs for audio contribution and distribution. For GatesAir, techniques such as Dynamic Stream Splicing used in their Intraplex products, leverage multiple low-cost connections simultaneously, to achieve credibility and security for broadcast content.
“The real innovation is that the broadcast industry got together to produce the standard the right way. Now, everything we need is set up in the ST 2110 standard, which is widely recognised. There is no fight for it: we follow it to the letter and it works for us,” said Ford from Imagine Communications.
Imagine Communications has delivered a number of IP-connected architectures globally, which rely on AES67 for audio. To quote an example, New York’s VICE Media has built a system using Imagine Communications AoIP technology, to provide a quick turnaround for an inspiring number of news stories. “The processing component of the solution involved moving media in and out of the IP domain, encapsulating legacy SDI signals into the IP network based on the SMPTE ST 2022-6 and AES67 standards, co-ordinated via VSF TR-04,” said Ford.
Another instance was in Brazil, where Imagine provided a platform on which TV Globo is building its transition from SDI to IP. Internally, audio is handled in AES67 form, and the architecture includes SDI-to-AES67 conversion, running on Imagine’s Selenio MCP3 processors.
England’s Isle of Wight Vectis Radio, faced infrastructural challenges whilst linking their studio to their uniquely-situated 25W transmitter. The Barix audio encoder and decoder in its STL workflow, along with the Barix Redundix IP audio resiliency, bolstered a feasible solution.
Over the past couple of years, GatesAir’s Intraplex IP Link AoIP codecs have been replacing expensive satellite links, at National Public Radio between remote studios. Similar executions can be witnessed at the Washington DC headquarters. The transport reliability methods within Intraplex audio codecs allowed GatesAir’s customers to reduce bandwidth costs while improving quality.
ON THE WISH-LIST
According to Ford, he would wish for the entire broadcast industry to shift to IP as fast as makes financial sense. “The AES67 will gain a larger footprint through ST 2110. My wish is for people to get out there and use it,” he added.
While reliability within the studio environment can be managed via in-house network engineering, wide-area AoIP transport can be susceptible to packet losses and security. Parikh commented on how this can be rectified, “While different codec vendors have their own methods to combat issues like security, having a specification with widespread support will go a long way in advancing the proliferation of AoIP technology globally.”
THE TOMORROW OF AoIP
As the broadcast community tends towards migrating to IP, the AES67 technical standard is expected to dominate audio transport technology. It endows users with the flexibility that they had in the traditional analogue/digital world, over a single IP interface. Whether in the case of trucks, production studios or sports events, AoIP comes across as a promising enabler of low-cost infrastructure.
“Lower costs will allow us broadcasters to be more dynamic in the services we offer. Advanced audio workflows using AES67 is one part of the migration to IP and virtualisation,” said Ford. “IP connectivity is at the heart, of the move to future software-defined architectures. In turn, that enables people working in television, to get on with their work, as quickly and cost-effectively as possible,” he added.
IP technology is becoming ubiquitous in wide-area and in-studio networks. Support for AES67 among different types of audio broadcast gears such as consoles, mixers, processors, exciters etc. is increasing. “This is something we at GatesAir, are addressing with the availability of our new IP Link 200A codec, which natively supports AES7 transport,” asid Parikh.
Implementation of an all-IP infrastructure, for contribution or distribution is gaining momentum, and is only expected to accelerate further, as the technologies behind IP networks continue to improve around the globe. The use of public IP infrastructure for broadcast applications is expected to rise, thus, bringing in a technological revolution in the audio industry. Till then, listen away!