Print This Page

8. Operational quality issues

8.2 Ethernet compliance

In the field of information technology (IT), Ethernet is the most prevalent world wide standard for networks. All computers, laptops, tablets and smartphones have some form of Ethernet connectivity to enable them to connect to other computers, printers, hard disks and, of course, the internet. For networked audio systems, it makes sense to include Ethernet so all of these functions can be supported additionally to the audio connections. As two other media-related fields - video and lighting control - also have embraced Ethernet as an efficient distribution protocol, a networked audio system that includes Ethernet can also include video and light control over the same cabling - increasing cost efficiency of integrated media systems. Finally, user interfaces increasingly utilize Ethernet, replacing USB and RS232/RS485. Examples are the many tablet apps available to control digital mixing consoles.

There are two ways to provide Ethernet connectivity in a networked audio system: Ethernet embedded systems and Ethernet compliant systems.

Ethernet embedded networked audio systems
A dedicated audio network protocol can include (or embed) an Ethernet tunnel that connects Ethernet ports on selected devices together as one Ethernet network. Examples are Optocore offering a 100Mb tunnel, and Rocknet offering a 10Mb tunnel. The advantage of dedicated audio protocols is that the network is fully managed by the audio designer - offering services to other functions under ‘audio’ supervision. The disadvantage is that the available tunnels mostly offer only unmanaged, low bandwidth Ethernet functionality.

Ethernet compliant networked audio systems
Audio network protocols that use Ethernet as the basic network technology offer the advantage of compatibility with appropiate Ethernet technologies and hardware on the IT market - with the choice of thousands of ‘off-theshelf’ hardware components (switches, media converters, wireless access points). As the IT market is one of the largest markets in the world, it is also the fastest developing market - increasing bandwidth and speed constantly. Fully compliant audio protocols can make use of these developments at very low cost. Examples of low bandwidth Ethernet compliant audio network protocols are EtherSound and CobraNet - both restricted to 100Mb data rates supporting up to 64 channels per cable. An example of a high bandwidth audio network protocol is Dante - using a 1Gb data rate, supporting up to 512 channels per cable. The advantage of Ethernet compliant networked audio systems is that they offer Ethernet connectivity for any Ethernet compliant service as a standard: video, light control, stage automation systems, user interfaces and many more services can be connected without the need for extra hardware. Also, as virtually all personal computers (PC’s) offer an Ethernet connection, modern Ethernet compliant audio networks such as Dante instantly allow all audio channels in the network to be recorded and played back by Digital Audio Workstations (or DAW’s) without the need for any additional interfaces.

Open and closed systems
Some manufacturers of networked audio devices use a proprietary audio network protocol that is only supported by the manufacturer, and not by others. Examples are Optocore - manufactured by Optocore GmbH, and Rocknet - manufactured by Riedel GmbH. The advantage of a closed protocol is that the compatibility between protocol and hardware can be very high - as all devices come from the same manufacturer. A disadvantage of a closed protocol is that a single manufacturer can only offer a limited range of products.

To allow system designers and sound engineers to combine networked audio devices from different manufacturers, an open networked audio protocol can be used - most commonly licensed to many manufacturers of audio devices by a dedicated network technology company such as Cirrus Logic (CobraNet), Digigram (EtherSound) and Audinate (Dante). The advantage of an open networked audio protocol is the high design freedom for the system designer, allowing devices from multiple manufacturers to be used in a system. A disadvantage of an open protocol is the many different implementations, requiring compatibility management.

The choice of an audio network protocol is an important tool for system designers and sound engineers to achieve efficiency in the design processes, and to deliver the desired compliance to customer requirements.

>>8.3 Redundancy

Return to Top