AVB was originally developed for live streaming transmission. In the meantime, it is increasingly used in industrial environments, in the Industrial Internet of Things (IIoT). This makes it unsuitable for Ethernet and automotive Ethernet , in order to improve real-time capability. Because of the underlying stochastic access method, its real-time capability is limited. This in turn leads to limited usability for audiovisual and multimedia applications.
Various extensions are intended to make Ethernet real-time capable, so that it can transmit sound and video data reliably and almost without delay in the network. AVB is one of them. In the current BMW 7 Series, it ensures the transmission of time-critical audio and video signals.
With AVB, which is covered by the IEEE 802.1 standard, frames are delivered deterministically. This makes the technology suitable for distributing high-quality audio sound as well as lip-synchronous playback for audio-video content. This is an essential feature for infotainment systems such as those in the BMW 7 Series. The Precision Time Protocol (PTP) provides the precise time information. It also ensures the timing and synchronization of time-critical applications by synchronizing all devices in the same domain with a grandmaster clock.
