Multicast - Motorola RSGu3502 User Manual

RSGu3502 — Advanced Configuration
38 RSGu3502 — Advanced Configuration

Multicast

Multicasting is a form of limited broadcast. UDP is used to send datagrams to all computers in a host group,
one or more hosts identified by the same destination IP address. The following statements apply to host
groups:
•
Anyone can join or leave a host group.
•
There are no restrictions on the host location.
•
There are no restrictions on the number of members that may belong to a host group.
•
A host may belong to multiple host groups.
•
Non-members can send UDP datagrams to the host group.
Multicasting is useful when the same data needs to be sent to more than one device; for example, if one
device is responsible for acquiring data that many other devices need. Using multicasting uses less network
bandwidth than sending the same data to individual devices.
Multicasting also enables you to receive multicast video streams from multicast servers. The residential
gateway supports an Internet Group Management Protocol (IGMP) proxy that handles IGMP messages.
When enabled, the residential gateway acts as a proxy for a LAN host making requests to join and leave mul-
ticast groups.
Field Description
Enable IGMP Enables an IGMP proxy for multicast messages. The residential gateway acts as a proxy for a
Multicast LAN computer requesting to join or leave multicast groups.