With the move away from signal-based workflows to digital file-based workflows, the need for IT routing and processing of content is increasing. Audio signal routing and control capabilities over Ethernet based systems are rapidly gaining acceptance for live sound because of its low latency.
The IEEE 802 Audio Video Bridging (AVB) Task Group is developing a set of technical standards that will allow the construction of a standards-based network with the proper quality of service (QoS) for audio and video production.
The following core improvements for Ethernet-based audio/video networks are needed:
- precise timing to support low-jitter media clocks and accurate synchronization of multiple streams (802.1AS);
- a stream reservation protocol (SRP) that allows an endpoint device to notify the various network elements in a path to reserve the resources necessary to support a particular stream (802.1Qat);
- forwarding and queuing rules that ensure that such a stream will pass through the network within the time specified by the reservation (802.1Qav).
IEEE 802.1Qat and 802.1Qav are amendments to the base IEEE 802.1Q document, which specifies the operation of “Virtual Bridged Local Area Networks” implemented by network devices typically called Ethernet switches.
Audio Streaming over Ethernet Network
AVB has the advantage that the standard is absolutely open, unlike other protocols already existing in the audio field (e.g. Cobranet, Ethersound). The audio-related organisation “AVnu” is taking care of the inter-operability of AVB devices.
Hirschmann
We see growing demands in theme parks, concert halls, sport arenas, musical theaters, cruise ships and others. The communication network is regarded as “mission critical.” For this reason, the requirements for switches in terms of reliability and robustness (e.g. mechanical, environmental) are very high. With its Hirschmann MACH1040, Belden already has a robustly designed fanless switch supporting IEEE 1588 PTPv2 (part of IEEE 802.1). The product is already creating demands in the A/V market.
AVB has the opportunity to become very popular. With developing standardization under the IEEE, it delivers the benefits of a common platform for developing breakthrough products. I am convinced that AVB will play a major role in the future. The network management, configuration and in-service maintenance cost savings from a media-friendly AVB switch will enable it to pay for itself quickly.
Our customers are driving initiatives for new switch generations from Belden’s Hirschmann brand. Stay tuned!
If you need more details about our solutions let me know. Email me at werner.eich@belden.com