Multicast; Chapter 24 Multicast; Multicast Overview; What You Can Do - ZyXEL Communications GS2210 Series User Manual

24.1 Multicast 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.

24.1.1 What You Can Do

• Use the Multicast Setup screen
configuration screens where you can configure IPv4 or IPv6 multicast settings.
• Use the IPv4 Multicast Status screen
information.
• Use the IGMP Snooping screen
forward group multicast traffic only to ports that are members of that group.
• Use the IPv6 Multicast Status screen
information,
• Use the MLD Snooping-proxy screen
to report group changes to a connected multicast router and forward MLD messages to other
upstream ports.
• Use the MVR screens
receiver port(s) and a source port for each multicast VLAN.

24.1.2 What You Need to Know

Read on for concepts on Multicasting that can help you configure the screens in this chapter.
IP Multicast Addresses
In IPv4, a multicast address allows a device to send packets to a specific group of hosts (multicast
group) in a different subnetwork. A multicast IP address represents a traffic receiving group, not
individual receiving devices. IP addresses in the Class D range (224.0.0.0 to 239.255.255.255) are
used for IP multicasting. Certain IP multicast numbers are reserved by IANA for special purposes
(see the IANA website for more information).
C
HAPTER
(Section 24.2 on page
(Section 24.3 on page
(Section 24.3.1 on page
(Section 24.4 on page
(Section 24.4.1 on page
(Section 24.5 on page 204) to create multicast VLANs and select the
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Multicast

190) to display the links to the
190) to view multicast group
191) to enable IGMP snooping to
196) to view multicast group
197) to enable the upstream port
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