Biamp Audia Classic Firmware Upgrade Procedure User Manual

AVB RESOURCE GUIDE

Covering the Basics of AVB

Table of Contents

AVB Brings AV and IT Together .................................................. 3

AVB for IT Professionals................................................................ 4

What is AVB and What Does It Do? ............................................................. 4

The AVB-Related IEEE Standards ............................................................... 4

Industry-Supported and Future-Proofed Solutions ................................. 4

How Does AVB Work? ................................................................... 5

Clocks: Accurate, Synchronized Communications .................................. 5

Endpoints: Talking and Listening .............................................................. 5

Key Features of AVB .................................................................................... 6

Why AVB? .......................................................................................... 8

Streamlined ........................................................................................ 8

Ecient ............................................................................................... 8

Simple ................................................................................................. 8

Innovative ........................................................................................... 9

AVB Questions and Answers ...................................................... 10

AVB Glossary ................................................................................. 16

AVB Brings AV and IT Together

The AV industry has experienced exponential growth in the last 10 years and
shows no signs of slowing down. The development of Digital Signal Processing
(DSP) has required a number of protocol innovations both in telephony and in
transporting digital media around a facility. Traditionally this has been handled
by the use of licensed or proprietary audio or video protocols. More recently
the development of the Audio Video Bridging (AVB) Protocol from the IEEE
allows standards to be used that deliver low latency, high channel count media
content.

These technological breakthroughs have
also heralded the biggest and most
important change of all: the convergence
of AV and IT. This change means
adopting new ways of doing business
and reinventing the ways we create value
for our customers. We’ve met this latest
challenge with the industry’s first truly
scalable media system for digital audio
networking using AVB: Biamp Tesira®.

Using AVB,

an IT manager can
have a mixed data
network, making their
responsibilities as the

In order to enable our customers to do
more with their AV systems–scale larger
and faster, facilitate more signals and
send signals further–we had to develop
a hardware platform that incorporated
cutting-edge technology and training and
support that expanded the Biamp legacy
for product innovation. Tesira is that
product, and AVB is its specialty.

This guide is a comprehensive support
resource about the basics of AVB, how end users can benefit from it, and what
we can expect from AVB in the future.

manager of

AV systems much
more time- and
cost-eective.

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AVB for IT Professionals

What is AVB and What Does It Do?

AVB is a collection of IEEE 802.1 standards that have increased the capacity
for information exchange, support and AV product standardization. Commonly
referred to as a switch, the purpose of an audio video bridge is to provide time­synchronized, low latency streaming capabilities for audio and video data that
guarantees bandwidth reservation.

The promise of AVB is a single network to transmit audio, video and other
forms of data via “smart” switches that can process AVB trac without
compromising network integrity. Using AVB, an IT manager can have a mixed
data network, making their responsibilities as the manager of AV systems
much more time- and cost-eective than parallel systems. Integrating AVB
technology into their current IT systems would be a giant step forward and a
radical shift in design philosophy most IT and AV administrators.

The AVB-Related IEEE Standards are as Follows:

• 802.1AS: Timing and Synchronization for Time-Sensitive Applications

• 802.1Qat: Stream Reservation Protocol (SRP)

• 802.1Qav: Forwarding and Queuing for Time-Sensitive Streams

• 802.1BA: Audio Video Bridging Systems

• 1722 is a Layer 2 transport protocol for time sensitive applications in

bridged LANs. Relates to media talker and listener endpoints only.

• 1733 is a Layer 3 transport protocol for time sensitive applications in
LANs that leverage Real-Time Transport Protocols (RTP) and RTP Control
Protocols (RTCP), two protocols commonly used in VoIP.

• P1722.1 is responsible for AVB device discovery, enumeration, connection
management and control for 1722-based devices. It is currently going
through the balloting process prior to acceptance.

Industry-Supported and Future-Proofed Solutions

AV equipment connections have historically been analog one-way, single­purpose and point-to-point. Even digital AV standards were often point­to-point and one-way, such asS/PDIFfor audio and theserial digital
interface(SDI) for video. This connection model resulted in large, confusing
masses of cables, especially in professional and high-end consumer
applications.

With the increase in larger scale project installations in recent years, AV
integrators are looking for system solutions that can accommodate their clients’
growing needs for more flexible and scalable options in their AV systems. Our
answer is to provide customers with an industry-supported and future-proofed
solution for their AV systems. As Biamp’s newest networked media system,
Tesira incorporates features and functionality that we’ve been developing since
the launch of AudiaFLEX. The biggest dierence in Tesira, as compared with
other similar systems, is the level of scalability it provides.

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How Does AVB Work?

Clocks: Accurate, Synchronized Communications

The commonly referenced network clock in every AVB-enabled device on a
network ensures that every device will have a very close representation of
what the precise time is in any given instance. After the devices communicate
with each other, one AVB device is selected as the best master clock and
communications proceed from talker endpoint to listener endpoint.

Endpoints: Talking and Listening

When an AVB talker endpoint device transmits one or more media streams to
the network, an AVB listener endpoint device receives one or more of those
streams from the network. The AVB bridge/switch acts as a conduit between
the two. Both the talker and listener endpoints request stream reservations and
the bridge between them fulfills those reservations, regulating the data streams
between both endpoints so they are receiving the correct data streams.

Step 1:
Talker endpoint advertises and listener endpoint receives the advertisement.

Talker Advertises

Endpoint

AVB

Switch

Endpoint

Endpoint Endpoint

AVB

Switch

AVB

Switch

Endpoint

Listener Receives

Advertisement

Step 2:

Talker endpoint is ready to send data and listener endpoint is ready to receive it.

Endpoint

Talker is Ready!

Ready!

Endpoint

Endpoint Endpoint

Ready!

Listener is ready!

Ready!

Endpoint

Page 5Biamp Systems | AVB Resource Guide

Step 3:

Talker endpoint sends stream and listener endpoint receives it.

Endpoint

Sending Stream!

Ready!

Endpoint

Endpoint Endpoint

Ready!

Receiving Stream!

Ready!

Endpoint

The AVB bridge/switch guarantees time-sensitive, loss-sensitive, real-time AV
data transmission while allowing audio and video data to seamlessly share the
same network. The switches will only allow up to 75% of each network port to
be used for AVB trac, preventing other forms of data from being delayed or
lost.

Key Features of AVB

• Transports media data faster and simultaneously by referencing a

network master clock.

• AVB devices periodically exchange timing information that allows both

ends of the link to synchronize their time base reference clock very
precisely across an AVB-aware LAN. This precise synchronization has
two purposes:

1. To allow accurate synchronization of multiple streams.

2. To provide a common time base for sampling/receiving data streams
at a source device, and presenting those streams at the destination
device with the same relative timing.

• Guarantees bounded, low and constant media latency. Low latency is
important in live situations where the receipt of audio needs to arrive
within milliseconds of the original transmission. Bounded/constant
latency prevents the timing from changing by guaranteeing a specific,
known latency between endpoints. The latency of AVB provides 2ms over
7 switch hops in a 100Mbit Ethernet network. With one gigabit hops, 1ms
latency becomes possible.

1ms latency OK!

1 gigabit hop

Switch

1 gigabit hop 1 gigabit hop

AVB

AVB

Switch

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