Igmp Snooping; Chapter 12 Igmp Snooping; Overview; Igmp Snooping Screen - ZyXEL Communications GS1200-5HP v2 User Manual

7.1 Overview

This chapter shows you how to configure various multicast features.
Traditionally, IP packets are transmitted in one of either two ways - Unicast (1 sender to 1 recipient) or
Broadcast (1 sender to everybody on the network). Multicast delivers IP packets to just a group of hosts
on the network.
IGMP (Internet Group Management Protocol) is a network-layer protocol used to establish membership
in a multicast group - it is not used to carry user data. Refer to RFC 1112, RFC 2236 and RFC 3376 for
information on IGMP versions 1, 2 and 3 respectively.
Note: You must enable IGMP snooping to use the IPTV service.
The following table introduces the IGMP snooping default settings of the Switch.
Table 8 IGMP Snooping Default Settings
Enable
Diable

IGMP Snooping

The Switch can passively snoop on IGMP packets transferred between IP multicast routers/switches and
IP multicast hosts to learn the IP multicast group membership. It checks IGMP packets passing through it,
picks out the group registration information, and configures multicasting accordingly. IGMP snooping
allows the Switch to learn multicast groups without you having to manually configure them.
The Switch forwards multicast traffic destined for multicast groups (that it has learned from IGMP
snooping or that you have manually configured) to ports that are members of that group. IGMP
snooping generates no additional network traffic, allowing you to significantly reduce multicast traffic
passing through your Switch.

7.2 IGMP Snooping Screen

Click IGMP Snooping in the navigation panel to display the screen as shown next.
IGMP Snooping
GS1200-5 GS1200-5HP V2
V
IGMP Static Router
Port will be set to
Auto.
GS1200 Series User's Guide
C
H A P T E R
GS1200-8
V
IGMP Static Router
Port will be set to
Auto.
V
45
7
GS1200-8HP V2
V