Igmp Status Screen; Figure 79 Igmp Proxy Network Example - ZyXEL Communications IES-1248-51 User Manual

IES-1248-51/51A/53 User's Guide
In IGMP proxy, an upstream interface is the port that is closer to the source (or the root of the
multicast tree) and is able to receive multicast traffic. There should only be one upstream
interface (also known as the query port) for one query VLAN on the IES-1248. A downstream
interface is a port that connects to a host (such as a computer).
The following figure shows a network example where A is the multicast source while
computers 1, 2 and 3 are the receivers. In the figure A is connected to the upstream interface
and 1, 2 and 3 are connected to the downstream interface.

Figure 79 IGMP Proxy Network Example

The IES-1248 will not respond to IGMP join and leave messages on the upstream interface.
The IES-1248 only responds to IGMP query messages on the upstream interface. The IES-
1248 sends IGMP query messages to the hosts that are members of the query VLAN.
The IES-1248 only sends an IGMP leave messages via the upstream interface when the last
host leaves a multicast group.
In daisychain mode, Ethernet interface 1 is set as the upstream interface and Ethernet interface
2 and the DSL ports are set as downstream interfaces.

20.3 IGMP Status Screen

Use this screen to view current IGMP information.
To open this screen, click Advanced Application, IGMP.
166 Chapter 20 IGMP