What is AVB?

Audio Video Bridging (AVB) is a collection of specialized IEEE Ethernet standards designed for transporting time-sensitive audio and video with predictable latency and synchronization.

AVB adds capabilities beyond those provided by a conventional Ethernet switch, including:

• Precise time synchronization using IEEE 802.1AS, commonly called gPTP
• Network resource and stream reservation
• Specialized traffic queuing and shaping for time-sensitive streams

These capabilities are useful for audio and video systems specifically designed to use AVB.

Do Alta Labs Switches Support AVB?

Alta Labs network switches do not support AVB.

In particular, Alta Labs switches do not implement the specialized AVB functionality required to act as an AVB bridge, including IEEE 802.1AS/gPTP and the associated AVB stream reservation and traffic-shaping mechanisms.

However, AVB support is not a general requirement for audio and video over Ethernet.

For most AV-over-IP deployments, the important question is not whether the switch supports AVB, but rather:

What network features does the AV equipment actually require?

Why Isn't AVB Included on Every Network Switch?

AVB requires capabilities that go beyond normal managed Ethernet switching.

Features such as hardware-assisted time synchronization, stream reservation, and deterministic traffic shaping require specialized support from the Ethernet switching chipset. Implementing these capabilities can also require additional licensing from chipset manufacturers.

As a result, AVB-capable switching hardware generally belongs to a significantly more expensive class of network equipment.

For an installation that specifically requires AVB, that additional hardware capability is necessary and appropriate. For networks that do not use AVB, however, the added cost provides no benefit to the applications running on the network.

Including specialized AVB hardware in every switch would therefore increase the cost of the switch for the vast majority of users who never require those features.

When is an AVB Switch Required?

An AVB-capable switch is required when the audio or video system being deployed specifically uses AVB.

For example, if the manufacturer of an audio processor, amplifier, console, speaker, video endpoint, or other AV device specifies that all switches in the media path must support AVB or Milan, an AVB-capable switch should be used.

AVB is not an enhancement that can be applied to arbitrary AV traffic. Both the network infrastructure and the AV endpoints must support the appropriate AVB protocols in order to use its timing, reservation, and traffic-shaping capabilities.

If the AV equipment does not use AVB, adding AVB support to the switch does not provide those applications with additional synchronization or bandwidth guarantees.

Most AV-over-IP Does Not Require AVB

Many AV-over-IP systems operate using standard Ethernet and IP networking rather than AVB.

Depending on the AV system, typical switch requirements may include:

• Gigabit or multi-gigabit Ethernet
• Sufficient switching and uplink bandwidth
• VLANs
• IGMP Snooping and an IGMP Querier for multicast traffic
• Quality of Service (QoS)
• Appropriate handling of multicast traffic
• Low latency and minimal packet loss

These are conventional managed-switch capabilities and should not be confused with AVB.

An AV system that requires VLANs, multicast management, QoS, or PTP traffic does not automatically require an AVB-capable switch.

PTP Does Not Necessarily Mean AVB

The term PTP can cause confusion when reviewing AV equipment requirements.

Several AV-over-IP technologies use the Precision Time Protocol (PTP) to synchronize endpoints. This does not automatically mean that the Ethernet switch must participate in clock synchronization or support AVB.

In many AV-over-IP systems, the endpoints themselves exchange PTP traffic through the network while the switch simply forwards the Ethernet or IP traffic normally.

AVB instead relies on the specialized IEEE 802.1AS generalized Precision Time Protocol (gPTP) as part of the AVB architecture. Supporting IEEE 802.1AS requires functionality beyond simply forwarding PTP packets.

A requirement for PTP traffic should therefore not be interpreted as a requirement for an AVB-capable switch unless the AV equipment manufacturer specifically requires AVB, IEEE 802.1AS/gPTP switching, or another switch-assisted timing feature.

AV Features Available on Alta Labs Switches

Alta Labs switches provide standard managed-network functionality commonly used by AV-over-IP systems, including:

• 802.1Q VLANs
• IGMP Snooping
• IGMP Querier functionality
• Quality of Service (QoS)
• High-bandwidth Ethernet switching

The specific configuration required depends on the AV system being deployed.

Always refer to the AV equipment manufacturer's network requirements when determining whether features such as IGMP Snooping, VLANs, multicast management, or QoS should be enabled.

AVB vs. Standard AV-over-IP Requirements

Choosing a Switch for an AV Deployment

Before determining that an AVB switch is necessary, review the network requirements published by the manufacturer of the AV equipment.

If the requirements call for standard networking capabilities such as Ethernet, VLANs, IGMP Snooping, multicast management, QoS, or the ability to transport PTP traffic, AVB support is not inherently required.

If the manufacturer explicitly requires an AVB- or Milan-capable network, IEEE 802.1AS/gPTP support from the switch, or other AVB-specific functionality, the deployment requires switches designed for that purpose.