IGMP devices

  • IGMP device:

    A switch or router running IGMP traffic control features.

  • IGMP host:

    An end-node device running an IGMP (multipoint or multicast communication) application.

  • Querier:

    A required IGMP device that facilitates IGMP protocol and traffic flow on a given LAN. This device tracks which ports are connected to devices (IGMP clients) that belong to specific multicast groups and triggers updates of this information. A querier uses data received from the queries to determine whether to forward or block multicast traffic on specific ports. When the switch has an IP address on a given VLAN, the switch automatically operates as a querier for that VLAN if it does not detect a multicast router or another switch functioning as a querier. When enabled (the default state), the switch’s querier function eliminates the need for a multicast router. In most cases, Hewlett Packard Enterprise recommends that you leave this parameter in the default enabled state even if you have a multicast router performing the querier function in your multicast group. For more information, see How IGMP operates.