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GS-2024 User’s Guide
125
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H A P T E R
18
Multicast
This chapter shows you how to configure various multicast features.
18.1 Multicast Overview
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.
18.1.1 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).
18.1.2 IGMP Filtering
With the IGMP filtering feature, you can control which IGMP groups a subscriber on a port
can join. This allows you to control the distribution of multicast services (such as content
information distribution) based on service plans and types of subscription.
You can set the Switch to filter the multicast group join reports on a per-port basis by
configuring an IGMP filtering profile and associating the profile to a port.
18.1.3 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.
Summary of Contents for Dimension GS-2024
Page 2: ......
Page 7: ...Safety Warnings GS 2024 User s Guide 7 This product is recyclable Dispose of it properly ...
Page 8: ...Safety Warnings GS 2024 User s Guide 8 ...
Page 26: ...List of Tables GS 2024 User s Guide 26 ...
Page 28: ...28 ...
Page 36: ...Chapter 2 Hardware Installation and Connection GS 2024 User s Guide 36 ...
Page 44: ...44 ...
Page 62: ...Chapter 6 System Status and Port Statistics GS 2024 User s Guide 62 ...
Page 70: ...Chapter 7 Basic Setting GS 2024 User s Guide 70 Figure 27 Basic Setting IP Setup ...
Page 74: ...Chapter 7 Basic Setting GS 2024 User s Guide 74 ...
Page 76: ...76 ...
Page 88: ...Chapter 8 VLAN GS 2024 User s Guide 88 ...
Page 110: ...Chapter 13 Mirroring GS 2024 User s Guide 110 ...
Page 120: ...Chapter 15 Port Authentication GS 2024 User s Guide 120 ...
Page 138: ...Chapter 18 Multicast GS 2024 User s Guide 138 ...
Page 152: ...Chapter 19 Authentication Accounting GS 2024 User s Guide 152 ...
Page 157: ...157 PART IV IP Application Static Route 159 Differentiated Services 163 DHCP 167 ...
Page 158: ...158 ...
Page 162: ...Chapter 21 Static Route GS 2024 User s Guide 162 ...
Page 166: ...Chapter 22 Differentiated Services GS 2024 User s Guide 166 ...
Page 174: ...174 ...
Page 198: ...Chapter 25 Access Control GS 2024 User s Guide 198 ...
Page 200: ...Chapter 26 Diagnostic GS 2024 User s Guide 200 ...
Page 204: ...Chapter 27 Syslog GS 2024 User s Guide 204 ...
Page 218: ...218 ...
Page 222: ...Chapter 32 Troubleshooting GS 2024 User s Guide 222 ...
Page 230: ...Chapter 33 Product Specifications GS 2024 User s Guide 230 ...
Page 232: ...232 ...
Page 240: ...Appendix A Pop up Windows JavaScripts and Java Permissions GS 2024 User s Guide 240 ...
Page 252: ...Appendix C Legal Information GS 2024 User s Guide 252 ...
Page 258: ...Appendix D Customer Support GS 2024 User s Guide 258 ...
Page 266: ...Index GS 2024 User s Guide 266 ...