User manual

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IGMP protocol: Enable/disable IGMP snooping.
IGMP fast leave: Enable/disable IGMP snooping fast leave. If enable, switch
will fast delete member who send leave report, else wait one second.
IGMP Querier: Enable/disable IGMP snooping querier. If select disable, the
switch can’t send query report.
3.2.3.5 Spanning Tree
STP provides tree topology for any arrangement of bridges and it also provides
a unique path between end stations on a network. In this way, it eliminates
loops.
Loops occur when alternate routes exist between hosts. Loops in an extended
network can cause bridges to forward traffic indefinitely, resulting in increased
traffic and reduced network efficiency. The device supports the following
Spanning two Protocol versions:
 STP: Provides a single path between end stations, avoiding and
eliminating loops.
 Multiple STP (MSTP)
Provides full connectivity for packets allocated to any VLAN. MSTP is based
on RSTP. In addition, MSTP transmits packets assigned to various VLANs
through different MST regions. MST regions act as a single bridge.
In STP, when the system detects L2 loops, it attempts to mitigate them by
preventing the involved port from transmitting traffic. Since loops exist on a
per-L2-domain basis, a problematic situation may occur wherethere is a loop in
VLAN A and no loop in VLAN B. If both VLANs are on Port X, and regular STP
wants to mitigate the loop, it stops traffic on the entire port, even for VLAN B
traffic, where there is no need. Multiple Spanning Tree Protocol (MSTP) solves
this problem by enabling several STP instances, so that it is possible to
detect/mitigate loops separately in each instance. By associating instances to