AV-over-IP Network Design

Design principles for reliable AV-over-IP — bandwidth planning, switch selection, multicast, VLANs, and PTP.

AV-over-IP replaces fixed matrix switchers with standard network gear, distributing video as multicast streams over Ethernet. It scales to huge, flexible any-to-any systems — but only if the network is designed for AV. Treated like ordinary office data, AV-over-IP floods switches and tears video apart. This guide covers the design decisions that make it reliable.

Start with bandwidth

Every stream consumes real bandwidth, and it varies enormously by technology:

Uncompressed / near-uncompressed (e.g. SDVoE) — ~8–10 Gbps per 4K stream; needs a 10G network.
Lightly compressed (JPEG2000, JPEG-XS) — hundreds of Mbps to ~1 Gbps; often fits on 1G per endpoint with a 10G backbone.
Heavily compressed (H.264/H.265) — tens of Mbps; 1G-friendly, higher latency.

Add up worst-case concurrent streams per link — especially uplinks, where many endpoints converge. Use the Bandwidth Calculator to size it, and remember the LAG and SDVoE considerations for aggregated links.

Switch selection

Not every “managed” switch handles AV multicast well. Require:

Non-blocking, line-rate switching at the needed speed (1G or 10G), with enough backplane for full concurrent load.
IGMP snooping with an active querier — mandatory, so multicast goes only to subscribed ports (see below).
Sufficient buffers for bursty uncompressed traffic.
PTP support if the AV platform needs clock sync (many do).
Fast enough uplinks — endpoints at 1G but uplinks/backbone at 10G+.

Multicast is non-negotiable

AV-over-IP uses multicast so one source can feed many displays without duplicating the stream. If the switch doesn’t constrain it, multicast floods every port like a broadcast and saturates the network. You must enable:

IGMP snooping on every switch carrying AV.
An IGMP querier (one per VLAN) so memberships are maintained.

See Multicast for AV for the full configuration.

Isolate AV traffic

Dedicated VLAN (or physical network) for AV keeps multicast, PTP, and broadcast domains contained and away from office traffic.
QoS / DSCP marking prioritizes AV and clock (PTP) traffic if the AV VLAN ever shares links.
Keep control, media, and management logically separated per the platform’s guidance.

Timing (PTP)

Many uncompressed platforms (SMPTE ST 2110, SDVoE, Dante-adjacent video) rely on PTP (Precision Time Protocol) to genlock endpoints. PTP needs switch support and a stable grandmaster; poor PTP shows up as tearing, judder, or audio drift.

A design checklist

Pick the codec/platform → this sets per-stream bandwidth and network speed (1G vs 10G).
Map worst-case concurrent streams per endpoint and per uplink; size with margin.
Choose switches that are non-blocking, IGMP-snooping, PTP-capable, and well-buffered.
Design the topology (leaf-spine for large systems); size uplinks for aggregate load.
Put AV on its own VLAN, enable IGMP snooping + a querier, mark QoS.
Validate PTP lock and multicast behavior before commissioning displays.

Rule of thumb

The two things that sink AV-over-IP projects are under-sized bandwidth on uplinks and missing multicast control (IGMP). Get those right and standard networking handles the rest.

Sources

SMPTE ST 2110 — professional media over managed IP networks (uncompressed AV transport).
SDVoE Alliance — 10 GbE uncompressed AV-over-IP architecture and per-stream bandwidth.
IEEE 1588 / SMPTE ST 2059 — Precision Time Protocol (PTP) for genlocking IP endpoints.
RFC 4541 — considerations for IGMP and MLD snooping switches.