Cabletron Systems SmartSTACK ELH100 - Manual (Page 27)

9033060 Product Overview 9
RMON
RMON (Remote Monitoring) is a facility used to manage networks
remotely while providing multi-vendor interoperability between monitoring
devices and management stations. RMON is defined by an SNMP MIB.
This MIB is divided into nine different groups, each gathering specific
statistical information or performing a specific function. RMON-capable
devices gather network traffic data and then store them locally until
downloaded to an SNMP management station.
The ELH100-12/24TX supports four of the nine groups of RMON defined
for Ethernet networks on a per segment basis. Specifically, these are:
• Statistics: a function that maintains counts of network traffic statistics
such as number of packets, broadcasts, collisions, errors, and
distribution of packet sizes.
• History: a function that collects historical statistics based on user-
defined sampling intervals. The statistical information collected is the
same as the Statistics group, except on a time stamped basis.
• Alarm: a function that allows managers to set alarm thresholds based
on traffic statistics. Alarms trigger other actions through the Event
group.
• Event: a function that operates with the Alarm group to define an
action that will be taken when an alarm condition occurs. The event
may write a log entry and/or send a trap message.
Because the Agent Module must be attached to either the 10 or 100 Mbps
stack segment, RMON can only be activated for one segment at a time.
You must therefore use an out-of-band connection to the Agent Module
to select the segment to activate for RMON. However, note that RMON
statistics and other information can only be viewed using a connection to
the on-board web agent or via other compatible SNMP management
applications.
Auto-Sensing and Auto-Negotiation
Auto-sensing is a process that permits the hub to automatically select the
operational speed of its ports. When an RJ-45 port on the base unit is
connected, the hub detects and configures the port to the speed of the
network the port is connected to, either 10 Mbps or 100 Mbps. Auto-
sensing is configurable in the Port Configuration Menu of the console
menus or via SNMP.
The 10Base-T/100Base-TX optional modules support auto-negotiation.
The port automatically negotiates the best connection possible with the
attached device. However, if the attached device must operate at full
duplex, then it must also support auto-negotiation. Otherwise, you can set
the mode manually using the mode selection switch on the module, or via
the management agent.
The 100Base-FX module does not support auto-negotiation. You need to
configure the duplex setting via the front panel switch.