TP-Link TL-SG3424 User Manual page 41

Default SNMP function : Enable
Default community name for GET: public
Default community name for SET: private
Default community name for Trap: public
Default Set function : Enable
Default trap host IP address: 0.0.0.0
Default port number :162
Trap:
In the switch, there are 6 trap hosts supported. Each of them has its own
community name and IP address; is user-definable. To set up a trap host
means to create a trap manager by assigning an IP address to host the
trap message. In other words, the trap host is a network management
unit with SNMP manager receiving the trap message from the managed
switch with SNMP agent issuing the trap message. 6 trap hosts can
prevent the important trap message from losing.
For each public trap, the switch supports the trap event Cold Start, Warm
Start, Link Down, Link Up and Authentication Failure Trap. They can be
enabled or disabled individually. When enabled, the corresponded trap
will actively send a trap message to the trap host when a trap happens. If
all public traps are disabled, no public trap message will be sent. As to
the Enterprise (no. 6) trap is classified as private trap, which are listed in
the Trap Alarm Configuration function folder.
Default for all public traps: Enable.
Fig. 3-24 Community and trap host setting
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User Manual
Publication date: January, 2006
Revision A2
User Manual
3-7. IGMP Snooping
The function, IGMP Snooping, is used to establish the multicast groups to
forward the multicast packet to the member ports, and, in nature, avoids wasting the
bandwidth while IP multicast packets are running over the network. This is because
a switch that does not support IGMP or IGMP Snooping can not tell the multicast
packet from the broadcast packet, so it can only treat them all as the broadcast
packet. Without IGMP Snooping, the multicast packet forwarding function is plain
and nothing is different from broadcast packet.
A switch supported IGMP Snooping with the functions of query, report and
leave, a type of packet exchanged between IP Multicast Router/Switch and IP
Multicast Host, can update the information of the Multicast table when a member
(port) joins or leaves an IP Multicast Destination Address. With this function, once a
switch receives an IP multicast packet, it will forward the packet to the members
who joined in a specified IP multicast group before.
The packets will be discarded by the IGMP Snooping if the user transmits
multicast packets to the multicast group that had not been built up in advance.
Fig. 3-25
Function name:
IGMP Snooping Status
Function description:
IGMP is used to snoop the status of IP multicast groups and display its
associated information in both tagged VLAN and non-tagged VLAN networks.
Enabling IGMP with either passive or active mode, you can monitor the IGMP
snooping information, which contains the multicast member list with the
multicast groups, VID and member port.
Publication date: January, 2006
Revision A2
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