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•
EtherLike MIB (RFC 1643),
Dot3StatsTable Group: Contains specific information about Ethernet
errors on each port (eg collisions, CRC errors, carrier sense errors, ...).
• RMON (RFC 1757):
- Statistics Group:
Contains Ethernet-specific statistics for each port (eg transmitted packets,
multicast packets, drop events, ...).
- Alarm Group:
lets you define a set of thresholds, if a threshold in an assumed direction is
exceeded, an event is triggered (see the following Event Group).
- Event Group:
Allows the definition of events (send trap and / or log local) that can be triggered
by other groups of RMON.
• Yacoub MIB:
- General Group:
Contains device and version information (both read-only)
- IP Group:
Contains objects to configure the IP stack (vs. DHCP. Hard-coded address)
- VLAN Group:
Provides a table to configure the VLAN functionality on the switch,
- QoS Group:
Contains objects to configure QoS
- SNMP Group:
Contains objects to configure the trap function of the transmitter switch.
As an example we take the request to the moment at which the system has been started. This value is
stored in the variable sysUpTime, which is located in the system group of MIB-II. The resulting object
identifier (OID) is shown in Table 4.2):
ISO
ORG
DOD
Internet
MGMT
MIB-II
System
sysUpTime
1
3
6
1
2
1
1
3
Table 4.2.: Object Identifier (OID)
To distinguish the different levels of the MIB tree, the individual numbers are separated by periods. To
designate one instance, and not only a specification, a zero is added. The resulting OID for the sysUpTime
variable is: 1.3.6.1.2.1.1.3.0. This OID can be shipped with a GetRequest to the switch, which responds
with a GetResponse message that contains the result.
