Allied Telesis AR400 Multiple potential Igmp queriers, Igmp proxy, Static Igmp, Igmp fast leave

Introduction >	Contents
Multiple potential IGMP queriers	15
Example	15
Explanation of multiple potential IGMP queriers	17
IGMP proxy	21
Example	21
Explanation of IGMP proxy	23
Query solicitation (rapid recovery from topology changes)	26
How query solicitation works	26
Why convergence takes so long without query solicitation	28
Speeding up IGMP convergence in a non-looped topology	33
Enabling query solicitation on multiple switches in a looped topology	33
IGMP filtering (controlling multicast distribution)	35
Example	35
Explanation of IGMP filtering (controlling multicast distribution)	38
IGMP throttling (limiting the number of streams for each subscriber)	40
Example	40
Explanation of IGMP throttling (limiting the number of streams for each subscriber) . 43
Static IGMP	48
Example	48
Explanation of Static IGMP	51
How clients leave groups: queries and timers	58
Overview of leave process	58
Querier timer values	58
Snooper timer values	59
Comparing the Querier and Snooper timers	60
Consequences for high-loss and high-lag networks	60
IGMP fast leave	61
Example	61
Explanation of IGMP fast leave	63
Configurable IGMP timers and counters	69
Timer and counter relationships	69
Software versions	70
Initial configuration	70
Default values	72
Last Member Query Count and Last Member Query Interval	72
Robustness Variable	75
Default Query Interval	76
Query Response Interval	77
Default Timeout Interval	78
Example of bad choices for timer values	83
Example	83
Problem 1: Last Member Query Interval too short	84
Problem 2: Query Response Interval short	84
Problem 3: Default Timeout Interval too short	84

Page 2 AlliedWare™ OS How To Note: IGMP