Multimedia Traffic Control with IP Multicast (IGMP)
How IGMP Operates
Querier's processing of that Leave. For more on this topic, refer to “Forced
ProCurve recommends that the following settings be used.
■Use Delayed Group Flush on the Series 2610 switches whenever Fast Leave or Forced Fast Leave are set on a port (see page
■Forced fast leave can be used when there are multiple devices attached to a port.
Automatica.Connected to only one end node
b.The end node currently belongs to a multicast group; i.e. is an IGMP client
c.The end node subsequently leaves the multicast group
Then the switch does not need to wait for the Querier status update interval, but instead immediately removes the IGMP client from its IGMP table and ceases transmitting IGMP traffic to the client. (If the switch detects multiple end nodes on the port, automatic
In the next figure, automatic
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| Server |
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| 3A |
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| 5A |
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| 7A |
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| 7B |
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| 7C |
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| activates on these |
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| two ports. |
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| Switch 7X |
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Routing |
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| Printer | ||
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Switch |
| A1 |
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| A3 |
| A4 A6 |
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| 7D | |||||||||
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Acting as |
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Querier |
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| ProCurve Switch with |
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| Automatic |
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| not activate on this port. |
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When client “3A” running IGMP is ready to leave the multicast group, it transmits a Leave Group message. Because the switch knows that there is only one end node on port A3, it removes the client from its IGMP table and halts multicast traffic (for that group) to port A3. If the switch is not the Querier, it