Multimedia Traffic Control with IP Multicast (IGMP)
How IGMP Operates
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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| 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 does not wait for the actual Querier to verify that there are no other group members on port A3. If the switch itself is the Querier, it does not query port A3 for the presence of other group members.
Note that
Using Delayed Group Flush
This feature continues to filter
Syntax: igmp delayedflush <time period>
Enables the switch to continue to flush
Syntax: Show igmp delayedflush
Displays the current setting for the switch.