How to Enable IGMP Snooping on UniFi Switches for IPTV
If you have IPTV devices on your network, such as set-top boxes (STBs) or smart TVs, you may want to enable IGMP snooping on your UniFi switches. IGMP snooping is a feature that allows switches to optimize multicast traffic delivery by forwarding it only to the ports that request it, instead of flooding it to all ports in the VLAN. This can reduce bandwidth consumption, improve network performance, and enhance security.
In this article, we will explain what IGMP snooping is, how it works, and how to enable it on UniFi switches for IPTV.
What is IGMP Snooping?
IGMP snooping is based on the Internet Group Management Protocol (IGMP), which is a protocol used by hosts and routers to communicate about multicast group membership. Multicast is a method of sending data to multiple destinations simultaneously, using a single source address and a group address. For example, IPTV uses multicast to stream video channels to multiple viewers at once.
However, not all devices on the network are interested in receiving the same multicast streams. For example, if you have three STBs on your network, each tuned to a different channel, they only need to receive the multicast packets for their respective channels, not for all channels. Therefore, IGMP allows hosts to join and leave multicast groups dynamically, by sending IGMP messages to their routers. Routers then use these messages to update their multicast routing tables and forward multicast packets accordingly.
IGMP snooping is a feature that allows switches to listen to these IGMP messages and learn which ports are members of which multicast groups. By doing so, switches can forward multicast packets only to the ports that belong to the same group as the source, instead of flooding them to all ports in the VLAN. This can save bandwidth, reduce network congestion, and prevent unwanted multicast traffic from reaching unauthorized hosts.
How Does IGMP Snooping Work?
To enable IGMP snooping on UniFi switches, you need two components: an IGMP snooper and an IGMP querier.
An IGMP snooper is a switch that monitors IGMP messages on its ports and builds a table of port-to-group mappings. For example, if an STB sends an IGMP join message for group 184.108.40.206 (a multicast address for a video channel) on port 5, the switch will add an entry in its table that port 5 belongs to group 220.127.116.11. Similarly, if an STB sends an IGMP leave message for group 18.104.22.168 on port 5, the switch will remove the entry from its table.
An IGMP querier is a device that periodically sends IGMP query messages to all ports in the VLAN, asking hosts to report their multicast group membership. This is necessary to maintain the accuracy of the port-to-group mappings, as hosts may join or leave groups without sending explicit IGMP messages. For example, if an STB is powered off or disconnected from the network, it will not send an IGMP leave message for its current group, so the switch will not know that port 5 is no longer a member of group 22.214.171.124. Therefore, the querier will send an IGMP query message every few minutes, asking hosts to respond with their current group membership. If port 5 does not reply with an IGMP report message for group 126.96.36.199 within a certain timeout period, the switch will assume that port 5 has left the group and remove the entry from its table.
By default, UniFi switches act as both IGMP snoopers and queriers on all VLANs. However, you can disable or enable these functions individually on each VLAN using the UniFi Controller software.
How to Enable IGMP Snooping on UniFi Switches for IPTV?
To enable IGMP snooping on UniFi switches for IPTV, you need to follow these steps:
Login to your UniFi Controller software and go to Settings > Networks.
Select the VLAN that you want to enable IGMP snooping on and click Edit.
Under Advanced Options, check the box next to aa16f39245