Motorola VT2442 ユーザーガイド
VT2442 Voice Gateway User Guide
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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:
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.
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 voice gateway
supports an Internet Group Management Protocol (IGMP) proxy that handles IGMP messages. When enabled,
the voice gateway acts as a proxy for a LAN host making requests to join and leave multicast groups.
supports an Internet Group Management Protocol (IGMP) proxy that handles IGMP messages. When enabled,
the voice gateway acts as a proxy for a LAN host making requests to join and leave multicast groups.
Multicast fields
Field
Description
Enable IGMP
Multicast
Multicast
Enables an IGMP proxy for multicast messages. The voice gateway acts as a proxy for a LAN
computer requesting to join or leave multicast groups.
computer requesting to join or leave multicast groups.