14 rmon, 1 statistics – Signamax Managed Hardened PoE Industrial DIN-rail Mount Switch User Manual
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14 RMON
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14 RMON
Remote Monitoring (RMON) is used to realize the monitoring and management from the
management devices to the managed devices on the network by implementing such
functions as statistics and alarm. The statistics function enables a managed device to
periodically or continuously track various traffic information on the network segments
connecting to its ports, such as total number of received packets or total number of oversize
packets received. The alarm function enables a managed device to monitor the value of a
specified MIB variable, log the event and send a trap to the management device when the
value reaches the threshold, such as the port rate reaches a certain value or the potion of
broadcast packets received in the total packets reaches a certain value.
Both the RMON protocol and the Simple Network Management Protocol (SNMP) are used for
remote network management:
RMON is implemented on the basis of the SNMP, which is thus enhanced. RMON sends
traps to the management device to notify the abnormality of the alarm variables by using
the SNMP trap packet sending mechanism. Although trap is also defined in SNMP, it is
usually used to notify the management device whether some functions on managed
devices operate normally and the change of physical status of interfaces. Traps in RMON
and those in SNMP have different monitored targets, triggering conditions, and report
contents.
RMON provides an efficient means of monitoring subnets and allows SNMP to monitor
remote network devices in a more proactive and effective way. The RMON protocol
defines that when an alarm threshold is reached on a managed device, the managed
device sends a trap to the management device automatically, so the management device
has no need to get the values of MIB variables for multiple times and compare them, and
thus greatly reducing the communication traffic between the management device and the
managed device. In this way, you can manage a large scale of network easily and
effectively.
14.1
This page shows the statistics of Stats Octets, Stats Pkts, Broadcastkts, MulticastPkts, CRC
Align Errors, Under size Pkts, Over size Pkts, Fragments, Jabbers, Collisions, Pkts 64 Octets,
Pkts 64 to 127 Octets, Pkts 128 to 255 Octets, Pkts 256 to 511 Octets, Pkts512 to 1023
Octets, Pkts1024 to 1518 Octets, and Drop Events of each Ethernet port.
Stats Octets:
The total number of octets of received and sent data, including bad packets,
received from network; it excludes framing bits but includes Frame Check Sequence (FCS)
octets.
Stats Pkts: The total number of packets received and sent, including bad packets, broadcast
packets and multicast packets.