HARMAN contributes open source software to Open AVB Project for low-latency, real-time automotive Ethernet
HARMAN has made an open source software contribution to the Open AVB project to help drive the adoption of Ethernet AVB/TSN (Audio Video Bridging/Time Sensitive Networking) in automotive, consumer, pro audio/video and industrial markets. In AVB/TSN, the maximum latency is deterministic and thus supports low-latency applications from live A/V to machine control.
Legacy Ethernet uses “best effort delivery”—i.e., data traffic flow is indeterminate, and intervening traffic can delay a data stream. Because of this uncertainty on receiving a stream packet, the receivers in legacy systems typically employ large buffers so as not to underflow, which would result in an audible click on an audio stream or loss of critical control information in a control stream.
AVB/TSN ensures the arrival of time-sensitive streams as well as when they will arrive. The FQTSS (Forwarding and Queuing of Time-Sensitive Streams) standard prioritizes AVB traffic ahead of legacy best-effort packets. AVB frames are forwarded with precedence over Best Effort traffic (i.e., reserved AVB stream traffic traversing an AVB bridge has forwarding precedence over non-reserved traffic) and will be subjected to traffic-shaping rules.
The traffic shaping rules require that frames be distributed very evenly in time, preventing “bunching” of frames. By controlling the queuing and data flow, an AVB/TSN system has the lowest possible latency. That latency is controlled and bounded by the rules of FQTSS.
The Audio Video Transport Protocol (AVTP) provides the streaming format within AVB. The lightweight protocol is intended to maximize bandwidth usage, with the low latency required for real-time applications.
HARMAN’s contributed technology includes major enhancements to the AVTP data pipeline and aims to modernize and prepare the connected car with flexible, scalable and secure in-vehicle networking technology while addressing an increased need for highly reliable communication in the vehicle.
As the auto industry continues to move towards realizing autonomous driving there is an increased need for highly dependable, cross-domain communication in the vehicle. Ethernet AVB represents a reliable solution. By replacing both the physical complexity of analog cables and the network complexity of earlier proprietary solutions, AVB brings an open, standards-based approach that enables interoperable platforms to offer more affordable and better market solutions, HARMAN said.
Backed by the AVnu Alliance, a community creating an interoperable ecosystem of low-latency, time-synchronized, highly reliable networked devices using open standards through certification, the Open AVB project provides essential network building blocks, drivers, libraries and example application best practices for building AVB/TSN systems.
A founding member of the AVnu Alliance, HARMAN has been actively contributing to its working groups and projects since the Alliance’s formation. This most recent contribution aims to enable and provide for a fully functioning, viable open source software stack, essential for the development and testing of Ethernet AVB products.
The AVnu Alliance is a community creating an interoperable ecosystem of low-latency, time-synchronized, highly reliable networked devices using open standards. AVnu creates comprehensive certification programs to ensure interoperability of networked devices.
The foundational technology enables deterministic synchronized networking based on IEEE Audio Video Bridging (AVB) / Time Sensitive Networking (TSN) base standards. The Alliance, in conjunction with other complimentary standards bodies and alliances, develops complete solutions in professional AV, automotive, industrial control and consumer segments.