A few words about Livewire+ and AES67

What is Livewire+™?

Livewire+ is the pioneering technology invented by the Telos Alliance to convey low-delay, high-reliability audio over switched Ethernet.

Introduced as Livewire™ in 2003, today’s Livewire+ is AES67-compliant. That means that it complies fully with the AES67-2013 Interoperability Standard, allowing AES67 devices to connect directly to Livewire+ networks and exchange audio streams. Livewire+ is also extensible, able to incorporate future AES standards when they are ratified. Livewire+ is also backward-compatible with the RAVENNA™ networking protocol.

With Livewire+, a single Ethernet cable carries real-time uncompressed digital audio, device control messages, program associated data, and even routine network traffic. An entire facility can be wired in hours, instead of weeks. All Axia Audio studio products, and most products from other Telos Alliance brands, utilize Livewire+ networking technology. Expanding or modifying your system is simple thanks to the inherent scalability and modularity of Livewire+.

Livewire+ offers a revolutionary change in how studios can be built. But at the same time, it's a natural continuation of general trends and what you already know.

How Livewire+ works

Livewire+ has an audio advertising system. Every source has a text name and numeric ID. These are transmitted from source devices to the network. Devices that play audio build lists of all available sources from which users can select.

Using xNode audio interfaces, you enter the names of your input sources via any PC with a web browser. With playout PCs attached to the network, you open a configuration window.

Livewire+ networks employ two types of audio streams. Livestreams have small, frequent packets optimized for live audio that requires very low (circa1 ms.) delay, for microphones and headphone audio. Standard Streams are also real-time streams, but with bigger packets, and are used for audio streams that don't require super-low latency - like audio from CD players, or that exchanged with automation system PCs. Devices that connect to Axia networks can transmit and receive both stream types; the user selects which type to generate when a device is initially configured.

A sophisticated phase-locked loop clocking system allows Livewire+ to use very small buffers for the least latency and ensures that audio channels remain time-aligned (as needed for multiple mics in a studio or for TV surround-sound mixing.)

Converged Networks

An Ethernet network used for Livewire+ audio can also be shared with other data transmissions, such as file transfers and web browsing. An Ethernet system with a switch at the center may have a mix of audio nodes and normal servers, PCs, etc. because the Ethernet switch directs traffic only to where it is needed.

Even on a single link, traffic can be mixed because we use modern Ethernet's priority mechanism to be sure audio packets have first priority on the link's bandwidth. A studio audio delivery system can use this capability to download an audio file from a server, for example, while simultaneously playing another audio file live.

Livewire+ maximizes the benefits of converged networking in the broadcast facility. Many stations using Livewire+ have computer data, telephone, audio, and control on a single network that uses computer industry-standard wiring, spurring cost-efficiencies throughout the plant.

Audio Quality

A Livewire+ network is a controlled, high-speed environment, with no risk of audio drop-outs from network problems and plenty of bandwidth for many channels of high-quality uncompressed audio. We use studio-grade 48kHz/24-bit PCM encoding. Axia digital xNode audio adapters deliver 138dB of dynamic range, with less than 0.0002% THD. Even analog xNodes have 100dB dynamic range, < 0.005% THD, and headroom to +24dBu.

Livewire+ is standards-based

Since the very beginning, The Telos Alliance has based its AoIP networking technologies on standards. IP (Internet Protocol), the networking standard that is the underpinning of nearly all critical business networks (and of the Internet itself) is the basis for Livewire+ AoIP.

As charter members of the AES X.192 Working Group, we helped define the AES67 standard — and became the first broadcast manufacturer to become AES67 compliant.

Livewire+ is so standards-based, in fact, that your audio can even be played by PC media players that support standard protocols and uncompressed PCM audio. The Internet’s IP standard for streaming media, called RTP/IP, is used for standard audio streams. RTP stands for Real-Time Protocol. RTP is the Internet’s standard way to transport streaming audio and video, just as TCP/IP is the standard for general data.

The Gold Standard

In the decade since the introduction of Livewire+, broadcasters have adopted it at an exponential rate; AoIP has become the new standard for broadcast facilities.

Consider these facts:

• There are over 6,000 studios worldwide built with Livewire+.

• More than 5,500 networked Axia consoles are at work daily.

• Over 80 Livewire+ Partner companies provide compatible hardware and software products.

• There are more than 60,000 individual Livewire+ devices in the field.

• Livewire+ is fully compliant with the AES67 Interoperability Standard.

Impressive, no? But there are even more exciting things in the future. The Telos Alliance, with one of the largest R&D groups in broadcast, is fully committed to AoIP interoperability. We’ve been proponents of open standards since Day 1, freely sharing our technology with interested Hardware and Software Partners. We were charter, supporting members of the X.192 Working Group that defined the AES67 standard, and as founding members of the Media Networking Allliance are actively engaged in work to promote and enhance standards-based AoIP networking.