| Measurement |
Description |
Measurement
Unit |
Interpretation |
| Availability |
Indicates
the availability of a network interface |
Percent
|
This value is 100 if an interface is operational - i.e., has an
operStatus of "up". The value is 0 otherwise.
|
| Data_xmit_rate |
Indicates the
rate of data being transmitted from the network interface over a network link. |
MB/Sec
|
This measurement
depicts the workload on a network link. |
| Data_recvd_rate |
The rate of data
being received by the network interface over a network link. |
MB/Sec
|
This measure also
characterizes the workload on a network link. |
| Speed |
Speed
of the network interface |
Mbps
|
Some network interface may dynamically change their speed over time
- based
on external factors/settings. By tracking the speed of an interface
over time, an administrator can be aware of such speed changes.
|
| Pct_bandwidth_used |
Indicates the
percentage utilization of the bandwidth available over a network link |
Percent
|
A value close to
100% indicates a network bottleneck. |
| In_errors |
Indicates
the rate of inbound packets that contained errors preventing them from being delivered to a higher-layer protocol |
Packets/Sec
|
Ideally, this value should be 0. |
| Out_errors |
Indicates
the rate at which outbound packets could not be delivered as they contained errors |
Packets/Sec
|
Ideally, this value should be 0. |
| In_discards |
Indicates
the rate at which inbound packets were discarded, though such packets did not contain any errors that could prevent them from being delivered to a higher-layer protocol |
Packets/Sec
|
One possible reason for discarding such a packet could be to free up buffer space. |
| Out_discards |
Indicates
the rate at which outbound packets were discarded, though such packets did not contian any errors that could prevent them from being delivered to a higher-layer protocol |
Packets/Sec
|
One possible reason for discarding such a packet could be to free up buffer space. |
| In_N_unicast |
Indicates the rate at which packets which were addressed as multicast or broadcast were received by this layer
|
Packets/Sec
|
|
| Out_N_unicast |
Indicates the rate at which packets which were addressed as multicast or broadcast were sent by this layer |
Packets/Sec
|
|
| In_unicast |
Indicates the rate at which packets which were not addressed as multicast or broadcast were received by this layer
|
Packets/Sec
|
|
| Out_unicast |
Indicates the rate at which packets which were not addressed as multicast or broadcast were sent by this layer |
Packets/Sec
|
|
| Unknown_protocols |
Indicates the rate at which unknown protocols were received |
Packets/Sec
|
For packet-oriented interfaces, this measure will report the number of packets received via the interface which were discarded because of an unknown or unsupported protocol. For character-oriented or fixed-length interfaces that support protocol multiplexing, this measure reports the number of transmission units received via the interface which were discarded because of an unknown or unsupported protocol. For any interface that does not support protocol multiplexing, this counter will always be 0.
|
| Queue_length |
Indicates the length of the output packet queue |
Number
|
A consistent increase in the queue length could be indicative of a network bottleneck.
|
|
Note:
The speed of a network
interface is based on the value of its SNMP MIB-II variable, which is
set using router-specific commands (e.g., the "bandwidth"
command of a Cisco router). When a network
interface has a fixed maximum speed limit (e.g., Ethernet), the
percentage bandwidth will be <= 100%.
In some instances, service providers offer a
minimum committed information rate (CIR). In such cases, the speed of
the network interface is not fixed and may be set to the minimum CIR. Since
user traffic may be in excess of the CIR at times, the percentage
bandwidth measure could exceed 100%. In such cases, the percentage
bandwidth measure is to be ignored. |