Shure Dante-enabled devices can exhibit communications issues when connected to managed switches where IGMP (Internet Group Protocol Management) Snooping is not configured correctly. These issues may manifest themselves as:
If you are not experiencing any of these issues, you likely do not need to worry about IGMP snooping. If you are experiencing one or more of these issues, then there are two possible solutions: disable IGMP Snooping and Multicast filtering, or configure IGMP Snooping on the switch correctly.
When to Disable IGMP SnoopingSmall, isolated networks with a single switch that have
only Shure or other Dante-enabled devices generally do not require IGMP snooping, as the amount of Multicast generated will be very low (Multicast traffic is used only for clocking, discovery, and control in these cases—not audio). In these cases, disable all Multicast filtering or use an unmanaged, gigabit switch that does not support EEE (ensure it is not listed under
Disqualified Network Switches for Shure Dante Devices).
When to Configure IGMP Snooping
IGMP Snooping is required when:
- Multicast Dante or AES67 flows are in use.
- Dante traffic is mixed with other Multicast traffic, such as Multicast video systems.
- Critical control systems are on the same network as Dante devices, such as Crestron/AMX/Extron control devices.
- Using Dante in 100M (Fast Ethernet) networks, as bandwidth is limited (we do not recommend using 100Mbps switches).
- Using a Wi-Fi access point on the same network as Dante devices (Dante multicast data can flood the Wi-Fi, and therefore we generally do not recommend using Wi-Fi access points on Dante networks).
IGMP Snooping helps prevent transmission of Multicast traffic to ports that don't need them. On larger, shared networks with Dante or AES67 multicast flows, IGMP Snooping greatly reduces the amount of Multicast traffic on the network by only forwarding Multicast data to the devices that request it. For more details on how IGMP works, please see Multicast and IGMP In Depth.
How to Configure IGMP Snooping
You should only attempt to configure IGMP Snooping on isolated AV networks. Do not make changes to an Enterprise network without proper authorization. Please refer to Configuring a Network Switch for Shure Devices and Dante/AES67 for detailed instructions on how to properly configure your network switch to support Shure Dante-enabled devices.
In some rare cases, you may need to add IGMP static filters to each Dante-enabled device port on the VLAN. Only add these if your switch does not work after configuring it according to our switch configuration guide, or when using high-bandwidth Multicast devices such as IP Video senders/receivers (such as Crestron NVX). Static filters ensure that the PTP, mDNS, Discovery, and audio traffic is always available throughout the VLAN. IGMP static filters may be required for:
- PTP traffic: 224.0.1.129 (01-00-5e-00-01-81)
- mDNS traffic: 224.0.0.251 (01-00-5e-00-00-fb)
- Shure Discovery: 239.255.254.253 (01-00-5e-7f-fe-fd)
- Dante Control: 224.0.0.230, 224.0.0.231, 224.0.0.232, and 224.0.0.233 (01-00-5e-00-00-e6, 01-00-5e-00-00-e7, 01-00-5e-00-00-e8, 01-00-5e-00-00-e9)
- The specific Dante or AES67 Multicast audio addresses in use.
Contact Shure Applications Engineering for assistance configuring IGMP static filters on your network.
For a detailed list of ports and protocols used by Shure Dante-enabled devices, please refer to
WWB6 Ports and Protocol Information.
Additional Tips
- Ensure that Filter Unregistered Multicast is not enabled. Some switches ship with this feature enabled. This blocks traffic that should be allowed (mDNS, PTP, Dante Discovery) and usually results in devices failing to appear in Dante Controller, Shure Update Utility, and Shure Designer.
- If you experience intermittent audio, then run a Wireshark trace on a PC connected to the Dante network. It may show IGMP Query messages from multiple sources. Contact Shure Applications Engineering for help interpreting Wireshark traces.
- Fast Leave will not harm a Dante network and is generally required for Multicast video traffic.
- Avoid IGMP proxies, unless you are CERTAIN you know how it behaves.