AVB audio and video data can only pass through network switches which support the IEEE AVB protocol standards. The protocol establishes a reserved network path with guaranteed latency between the transmitter and receiver. AVB traffic will not establish or pass over network switches or routers that are not AVB compatible. Physical network topology and switch latency considerations are critical for an AVB media network design. If any switches suffer increased latency or bandwidth congestion, video and audio may jitter or fail entirely. Review the Media Network Overview section for more details and visit support.biamp.com for technical network compatibility articles.
The Tesira AVB-1 card allows server-class devices to share digital audio with devices which support the Audio Video Bridging (AVB) protocol, as defined by IEEE 802.1. Each AVB card can transmit up to 420 channels and receive up to 420 channels of audio. Audio channels must be grouped into up to 64 AVB streams, and each stream can be comprised of up to 60 channels. As the number of streams being used increases, the maximum channel count of an AVB-1 card may decrease. A single one channel stream is reserved as a pilot stream channel for media clocking between AVB devices included in a system.
See the table below for an example of maximum channel counts in situations where all streams contain the same number of channels. This table accounts for a single one channel stream which is reserved as a pilot stream channel for media clocking between AVB devices included in a Tesira system:
|
Channels per stream |
Maximum channel count |
|
60 |
419 (7 streams) |
|
32 |
416 (13 streams) |
|
16 |
400 (25 streams) |
|
8 |
352 (44 streams) |
|
4 |
256 (64 streams) |
|
2 |
128 (64 streams) |
|
1 |
64 (64 streams) |
Each TesiraFORTÉ AVB device can transmit up to 128 channels and receive up to 128 channels of audio. Audio channels must be grouped into up to 63 AVB streams, and each stream can be comprised of up to 60 channels. As the number of streams being used increases, the maximum channel count may decrease.
See the table below for an example of maximum channel counts in situations where all streams contain the same number of channels. This table accounts for a single one channel stream which is reserved as a pilot stream channel for media clocking between AVB devices included in a Tesira system:
|
Channels per stream |
Maximum channel count |
|
60 |
128 (2 streams) |
|
32 |
128 (4 streams) |
|
16 |
128 (8 streams) |
|
8 |
128 (16 streams) |
|
4 |
128 (32 streams) |
|
2 |
128 (64 streams) |
|
1 |
64 (64 streams) |
Each Tesira Amplifier device can transmit up to 32 channels and receive up to 32 channels of audio. Audio channels must be grouped into up to 32 AVB streams, and each stream can be comprised of up to 32 channels. As the number of streams being used increases, the maximum channel count may decrease.
See the table below for an example of maximum channel counts in situations where all streams contain the same number of channels. This table accounts for a single one channel stream which is reserved as a pilot stream channel for media clocking between AVB devices included in a Tesira system:
|
Channels per stream |
Maximum channel count |
|
16 |
32 (2 streams) |
|
8 |
32 (4 streams) |
|
4 |
32(8 streams) |
|
2 |
32 (16 streams) |
|
1 |
32 (32 streams) |
The TesiraXEL 1200 amplifiers are capable of daisy-chaining devices via an internal switch. The TesiraXEL 1200 has two ethernet ports: one port will connect to the main network while the provides network connectivity to downstream Biamp devices. When configured for daisy-chain mode, at least one Biamp AVB device must be plugged into one of the ports.
TesiraLUX video server-class devices have a fixed AVB stream count. The TesiraLUX IDH-1 provides 4 or 5 streams and the TesiraLUX OH-1 has a single pilot connectivity stream. The audio streams can be transmitted to other Tesira devices or recombined and delivered lip-synced to the video stream at the OH-1 display output. Audio streams transmitted or received from a Tesira audio server-class device will count toward to the AVB stream and channel limits of that device. Consult the table below for TesiraLUX audio and video stream sizes.
|
Stream # |
CH Count |
IDH-1 Stream Description |
|
|
1 |
1 |
Video Stream |
|
|
2 |
9 |
7.1 PCM HDMI Embedded Audio |
|
|
3 |
9 |
Analog input |
NOTE: Analog input streams will become a 9-channel single stream if “Single stereo port” is configured on the AV Input block. |
|
4 |
9 |
Analog input |
|
|
5 |
9 |
Analog input |
|
Due to the high bandwidth requirements of AVB video streams, consult the site network design for switch uplink and performance limitations. AVB stream path reservation may fail if there are any network links with insufficient bandwidth available between AVB talkers and listeners.
TesiraLUX supports HDCP. See HDCP Management for more information.
AVB Expanders such as the EX-IN, EX-OUT, EX-IO, EX-MOD, EX-UBT, Tesira Plenum-Mount Amplifiers and Lab.gruppen Amplifier have a single network port which shares responsibility for both AVB and Control Network communications. Therefore, for Tesira systems which use AVB Expanders, the AVB Network and Control Network must be the same network. AVB Audio Expanders (EX-MOD, EX-AEC, EX-IN, EX-OUT, EX-IO, EX-UBT Tesira Amplifiers - Plenum Mount, Parlé Microphones and Lab.gruppen Amplifier) do not support AVB blocks.
Each AVB Expander chooses a Tesira server to act as its proxy server. All Control Network communications to and from the expander are routed through its proxy server. For this reason, an AVB Expander must always reside on the same subnet as its proxy server. The proxy server for each expander can be assigned manually in the Equipment Table; otherwise it will be assigned automatically by the Tesira software.
NOTE: Although technically expander-class devices, AMP-450P/450BP and TCM-1A/TCM-XA will appear in the amplifier and/or microphone sections in other areas of this documentation for practical purposes.
A room system comprised of TesiraCONNECT devices may contain up to four TesiraCONNECT units in chain, which allows up to 14 Tesira endpoint devices (see System Limits). Assuming each device consumes up to four AVB streams, a room system using the maximum of four TesiraCONNECT devices results in a maximum of 56 AVB streams supported. See the table below:
|
TesiraCONNECT Units |
Total Ports |
Ports Used by Chains |
Tesira Devices |
Max AVB Stream Count |
|
4 |
20 |
6 |
14 |
150 |
|
3 |
15 |
4 |
11 |
150 |
|
2 |
10 |
2 |
8 |
150 |
|
1 |
5 |
0 |
5 |
150 |
The Tesira SERVER-IO and SERVER AVB-1 card features a Primary and Secondary network port. The secondary port is not to be used for daisy chaining. The Secondary port can optionally be used to support a redundant network configuration. When connected, the secondary port is a mirror of the primary port and will send out any data as sent out of the primary port, and receive any data just as the primary port would do. If either of the ports fail, the other port will continue sending and receiving AVB data.
| Note |
|
Audio Expander devices do not currently support AVB Redundancy, and will not receive audio from the Secondary port of a SERVER IO or SERVER. TesiraLUX video devices do not provide redundancy and will not failover between 10GbE SPF+ and 1GbE network connections |
Tesira software offers two latency settings for AVB data: 2ms and 1ms. These latency times represent the amount of time it will take to transmit an AVB network packet from one device to another. However, if the total network latency from one device to another ever exceeds the latency value selected in Tesira software, packets may be dropped. Audio and video may experience stuttering or dropouts.
The table below shows approximate maximum switch hop values, assuming Gigabit network switches are being used; the exact values will depend on the network switches used and network traffic levels.
|
Approximation of how many Gigabit network switch hops are allowable for a given AVB latency setting. Actual values will depend on the network switches used and network traffic levels, and may be significantly higher or lower. |
The latency setting is configured in Tesira software under Tools > Options > Document Settings > Network Latency.