Glossary

AAF

Short definition: Audio Format in Milan Streams.

Explanation: AVTP Audio Format.

Reference: IEEE 1722-2016, Clause 7

ADC

Short definition: Analog-to-Digital Converter.

Explanation: Converts analog signals into digital signals.

ATDECC

Short definition: Control protocol for Milan.

Explanation: Short for “AVB/TSN Device Discovery, Enumeration, Connection Management, and Control”.

Reference: IEEE 1722.1-2021

AVB

Short definition: Audio Video Bridging.

Explanation: Describes the basis for Milan .

Reference: IEEE 802.1BA-2011

AVTP

Short definition: Audio Video Transport Protocol.

Explanation: Specifies the media transport in a Milan network.

Reference: IEEE 1722-2016

AVTPDU

Short definition: AV-Transmission-Protocol Data Unit.

Explanation: Defines the Protocol Data Unit (PDU) format for Audio-Video traffic in AVB networks.

Reference: IEEE 1722-2016

Avnu Alliance

Short definition: Industry alliance to develop Milan.

Explanation: The Avnu Alliance is a consortium of member companies working together to create an interoperable ecosystem of low-latency, time-synchronized, highly reliable networking devices using the IEEE open standard TSN .

Reference: Avnu Alliance Website

BTCA

Short definition: Best TimeTransmitter Clock Algorithm.

Explanation: Formerly known as “Best Master Clock Algorithm”. Used to determine the best gPTP Clock Leader in a network.

Reference: IEEE 802.1AS-2011, Clause 10.3

Bridge

Explanation: Switch and Bridge are used synonymously. A Switch forwards traffic from one port to another. AVB switches must be time-aware (see: Network timing) and support traffic shaping (see: Traffic shaping).

CRF

Short definition: Clock Reference Format.

Explanation: Mechanism to improve audio clock accuracy in Milan networks. Commonly referred to as Media Clock.

Reference: IEEE 1722-2016, Clause 10

DAC

Short definition: Digital-to-Analog Converter.

Explanation: Converts digital signals into analog signals.

Delay

Short definition: The time offset applied to a Stream before playback.

Explanation: ‘In audio streaming, Delay refers to the time offset applied to a Stream before it is played out. The technical specification defines this as Presentation Time Offset (PTO ), while the Milan Manager refers to it as Presentation Time. Regardless of terminology, the function remains the same: it ensures that streams are synchronized by introducing a controlled delay before playback.’

Egress port

Short definition: Traffic exit port.

Explanation: Describes a port through which traffic is exiting a device. Used to describe the traffic flow in a Switch .

Endstation

Short definition: Converts audio to/from Milan.

Explanation: A device converting audio into or from the Milan network. An Endstation is Milan certified.

Reference: IEEE 802

Traffic Shaping

Short definition: Forwarding and Queuing for Time-Sensitive Streams.

Explanation: Specifies how to handle traffic of different priorities and ensures that Milan traffic arrives on time at the Listener .

Reference: IEEE 802.1Q-2014, Clause 34

FQTSS

Short definition: Forwarding and Queuing for Time-Sensitive Streams.

Explanation: Specifies how to handle traffic of different priorities and ensures that Milan traffic arrives on time at the Listener .

Reference: IEEE 802.1Q-2014, Clause 34

GM

Short definition: GrandMaster.

Explanation: The GrandMaster provides the global network time using the gPTP protocol. It is elected using the BTCA .

Reference: IEEE 802.1AS-2011

IEEE

Short definition: Institute of Electrical and Electronics Engineers.

Explanation: The IEEE is a US-American professional association for electrical engineering, electronics engineering, and other related disciplines.

Reference: IEEE Website

Ingress port

Short definition: Traffic input port.

Explanation: Describes a port through which traffic is entering a device. Used to describe the traffic flow in a Switch .

Listener

Short definition: Stream receiver

Explanation: The receiver of a Stream sent by a Talker .

Reference: IEEE 802.1BA-2011, Clause 3

MAC

Short definition: Medium Access Control.

Explanation: Layer that controls the hardware responsible for interaction with the wired or wireless transmission medium.

Reference: IEEE 802

MSRP

Short definition: Multiple Stream Registration Protocol.

Explanation: Facilitates the reservation and management of multiple Streams in a coordinated manner. It is an extension to SRP .

Reference: IEEE 802.1Q-2014, Clause 35

Media Time

Short definition: Audio clock timing.

Explanation: The local timing used to control audio sampling rates on a device. Media Time is derived from Network Time but is used specifically for media clock recovery and sample-accurate playback.

Milan

Short definition: Media Independent Local Area Network.

Explanation: The term Milan is used to describe a ProAV network based on the AVB specifications.

Reference: Milan-v1.2

Network Time

Short definition: Shared time base.

Explanation: A common time reference shared by all devices in a Milan network, established using the gPTP protocol. This ensures precise synchronization across the entire network.

Transport Layer

Short definition: Path through a computer system.

Explanation: The OSI Layer model is an abstract way to describe the path a packet has to take through a computer system.

Reference: Wikipedia OSI model

OSI Layer

Short definition: Path through a computer system.

Explanation: The OSI Layer model is an abstract way to describe the path a packet has to take through a computer system.

Reference: Wikipedia OSI model

PCM

Short definition: Pulse Code Modulation.

Explanation: A lossless compression method for audio signals.

PTO

Short definition: Presentation Time Offset.

Explanation: The playout time for samples in a packet transmitted from a Talker . Also known as Delay .

PTPv2

Short definition: Precision Timing Protocol v2.

Explanation: Precision Timing Protocol version 2. This is the basis for gPTP .

Reference: IEEE 1588-2008

Primary

Short definition: Primary connection.

Explanation: In a redundant network, the first connection is called Primary. The second connection is called Secondary .

Reference: Milan-v1.2, Clause 8.2.2

Stream Reservation

Short definition: Stream Reservation Protocol.

Explanation: Handles the reservation of references for individual Streams .

Reference: IEEE 802.1Q-2014, Clause 35

SRP

Short definition: Stream Reservation Protocol.

Explanation: Handles the reservation of references for individual Streams .

Reference: IEEE 802.1Q-2014, Clause 35

Secondary

Short definition: Secondary connection.

Explanation: In a redundant network, the second connection is called Secondary. The first connection is called Primary .

Reference: Milan-v1.2, Clause 8.2.2

Stream

Short definition: Container for audio or clock data.

Explanation: Used to transmit data between a Talker and a Listener within a network. Basis for the bandwidth reservation calculation. More explanation

Reference: IEEE 1722-2016

Switch

Short definition: Forwards network traffic between ports

Explanation: Switch and Bridge are used synonymously. A Switch forwards traffic from one port to another. AVB switches must be time-aware (see: Network timing) and support traffic shaping (see: Traffic shaping).

TSN

Short definition: Time Sensitive Networking.

Explanation: Evolved from the IEEE AVB working group. TSN is the basis for AVB .

Reference: IEEE TSN TG website

Talker

Short definition: Stream producer.

Explanation: The source of a Stream to be received by a Listener .

Reference: IEEE 802.1BA-2011, Clause 3

gPTP

Short definition: Generalized Precision Timing Protocol.

Explanation: The Generalized Precision Timing Protocol (gPTP) is a profile of PTPv2 . It provides precise timing and synchronization in Ethernet networks.

Reference: IEEE 802.1AS-2011