RMON-MIB (1.3.6.1.2.1.16)

Definition point for RMON notifications.

The SNMP trap that is generated when an alarm
entry crosses its rising threshold and generates
an event that is configured for sending SNMP
traps.

The SNMP trap that is generated when an alarm
entry crosses its falling threshold and generates
an event that is configured for sending SNMP
traps.

A list of Ethernet statistics entries.

A collection of statistics kept for a particular
Ethernet interface.  As an example, an instance of the
etherStatsPkts object might be named etherStatsPkts.1

The value of this object uniquely identifies this
etherStats entry.

This object identifies the source of the data that
this etherStats entry is configured to analyze.  This
source can be any ethernet interface on this device.
In order to identify a particular interface, this object
shall identify the instance of the ifIndex object,
defined in RFC 2233 [17], for the desired interface.
For example, if an entry were to receive data from
interface #1, this object would be set to ifIndex.1.

The statistics in this group reflect all packets
on the local network segment attached to the identified
interface.

An agent may or may not be able to tell if fundamental
changes to the media of the interface have occurred and
necessitate an invalidation of this entry.  For example, a
hot-pluggable ethernet card could be pulled out and replaced
by a token-ring card.  In such a case, if the agent has such
knowledge of the change, it is recommended that it
invalidate this entry.

This object may not be modified if the associated
etherStatsStatus object is equal to valid(1).

The total number of events in which packets
were dropped by the probe due to lack of resources.
Note that this number is not necessarily the number of
packets dropped; it is just the number of times this
condition has been detected.

The total number of octets of data (including
those in bad packets) received on the
network (excluding framing bits but including
FCS octets).


This object can be used as a reasonable estimate of
10-Megabit ethernet utilization.  If greater precision is
desired, the etherStatsPkts and etherStatsOctets objects
should be sampled before and after a common interval.  The
differences in the sampled values are Pkts and Octets,
respectively, and the number of seconds in the interval is
Interval.  These values are used to calculate the Utilization
as follows:

                 Pkts * (9.6 + 6.4) + (Octets * .8)
 Utilization = -------------------------------------
                         Interval * 10,000

The result of this equation is the value Utilization which
is the percent utilization of the ethernet segment on a
scale of 0 to 100 percent.

The total number of packets (including bad packets,
broadcast packets, and multicast packets) received.

The total number of good packets received that were
directed to the broadcast address.  Note that this
does not include multicast packets.

The total number of good packets received that were
directed to a multicast address.  Note that this number
does not include packets directed to the broadcast


address.

The total number of packets received that
had a length (excluding framing bits, but
including FCS octets) of between 64 and 1518
octets, inclusive, but had either a bad
Frame Check Sequence (FCS) with an integral
number of octets (FCS Error) or a bad FCS with
a non-integral number of octets (Alignment Error).

The total number of packets received that were
less than 64 octets long (excluding framing bits,
but including FCS octets) and were otherwise well
formed.

The total number of packets received that were
longer than 1518 octets (excluding framing bits,
but including FCS octets) and were otherwise
well formed.

The total number of packets received that were less than
64 octets in length (excluding framing bits but including
FCS octets) and had either a bad Frame Check Sequence
(FCS) with an integral number of octets (FCS Error) or a
bad FCS with a non-integral number of octets (Alignment
Error).

Note that it is entirely normal for etherStatsFragments to
increment.  This is because it counts both runts (which are
normal occurrences due to collisions) and noise hits.

The total number of packets received that were
longer than 1518 octets (excluding framing bits,
but including FCS octets), and had either a bad
Frame Check Sequence (FCS) with an integral number
of octets (FCS Error) or a bad FCS with a non-integral
number of octets (Alignment Error).

Note that this definition of jabber is different
than the definition in IEEE-802.3 section 8.2.1.5
(10BASE5) and section 10.3.1.4 (10BASE2).  These
documents define jabber as the condition where any
packet exceeds 20 ms.  The allowed range to detect
jabber is between 20 ms and 150 ms.

The best estimate of the total number of collisions
on this Ethernet segment.

The value returned will depend on the location of the
RMON probe. Section 8.2.1.3 (10BASE-5) and section
10.3.1.3 (10BASE-2) of IEEE standard 802.3 states that a
station must detect a collision, in the receive mode, if
three or more stations are transmitting simultaneously.  A
repeater port must detect a collision when two or more


stations are transmitting simultaneously.  Thus a probe
placed on a repeater port could record more collisions
than a probe connected to a station on the same segment
would.

Probe location plays a much smaller role when considering
10BASE-T.  14.2.1.4 (10BASE-T) of IEEE standard 802.3
defines a collision as the simultaneous presence of signals
on the DO and RD circuits (transmitting and receiving
at the same time).  A 10BASE-T station can only detect
collisions when it is transmitting.  Thus probes placed on
a station and a repeater, should report the same number of
collisions.

Note also that an RMON probe inside a repeater should
ideally report collisions between the repeater and one or
more other hosts (transmit collisions as defined by IEEE
802.3k) plus receiver collisions observed on any coax
segments to which the repeater is connected.

The total number of packets (including bad
packets) received that were 64 octets in length
(excluding framing bits but including FCS octets).

The total number of packets (including bad
packets) received that were between
65 and 127 octets in length inclusive
(excluding framing bits but including FCS octets).

The total number of packets (including bad
packets) received that were between
128 and 255 octets in length inclusive
(excluding framing bits but including FCS octets).

The total number of packets (including bad
packets) received that were between
256 and 511 octets in length inclusive
(excluding framing bits but including FCS octets).

The total number of packets (including bad
packets) received that were between
512 and 1023 octets in length inclusive
(excluding framing bits but including FCS octets).

The total number of packets (including bad
packets) received that were between
1024 and 1518 octets in length inclusive
(excluding framing bits but including FCS octets).

The entity that configured this entry and is therefore
using the resources assigned to it.

The status of this etherStats entry.

A list of history control entries.

A list of parameters that set up a periodic sampling of
statistics.  As an example, an instance of the
historyControlInterval object might be named
historyControlInterval.2

An index that uniquely identifies an entry in the
historyControl table.  Each such entry defines a
set of samples at a particular interval for an
interface on the device.

This object identifies the source of the data for
which historical data was collected and
placed in a media-specific table on behalf of this
historyControlEntry.  This source can be any
interface on this device.  In order to identify


a particular interface, this object shall identify
the instance of the ifIndex object, defined
in  RFC 2233 [17], for the desired interface.
For example, if an entry were to receive data from
interface #1, this object would be set to ifIndex.1.

The statistics in this group reflect all packets
on the local network segment attached to the identified
interface.

An agent may or may not be able to tell if fundamental
changes to the media of the interface have occurred and
necessitate an invalidation of this entry.  For example, a
hot-pluggable ethernet card could be pulled out and replaced
by a token-ring card.  In such a case, if the agent has such
knowledge of the change, it is recommended that it
invalidate this entry.

This object may not be modified if the associated
historyControlStatus object is equal to valid(1).

The requested number of discrete time intervals
over which data is to be saved in the part of the
media-specific table associated with this
historyControlEntry.

When this object is created or modified, the probe
should set historyControlBucketsGranted as closely to
this object as is possible for the particular probe
implementation and available resources.

The number of discrete sampling intervals
over which data shall be saved in the part of
the media-specific table associated with this
historyControlEntry.


When the associated historyControlBucketsRequested
object is created or modified, the probe
should set this object as closely to the requested
value as is possible for the particular
probe implementation and available resources.  The
probe must not lower this value except as a result
of a modification to the associated
historyControlBucketsRequested object.

There will be times when the actual number of
buckets associated with this entry is less than
the value of this object.  In this case, at the
end of each sampling interval, a new bucket will
be added to the media-specific table.

When the number of buckets reaches the value of
this object and a new bucket is to be added to the
media-specific table, the oldest bucket associated
with this historyControlEntry shall be deleted by
the agent so that the new bucket can be added.

When the value of this object changes to a value less
than the current value, entries are deleted
from the media-specific table associated with this
historyControlEntry.  Enough of the oldest of these
entries shall be deleted by the agent so that their
number remains less than or equal to the new value of
this object.

When the value of this object changes to a value greater
than the current value, the number of associated media-
specific entries may be allowed to grow.

The interval in seconds over which the data is
sampled for each bucket in the part of the
media-specific table associated with this
historyControlEntry.  This interval can
be set to any number of seconds between 1 and
3600 (1 hour).

Because the counters in a bucket may overflow at their


maximum value with no indication, a prudent manager will
take into account the possibility of overflow in any of
the associated counters.  It is important to consider the
minimum time in which any counter could overflow on a
particular media type and set the historyControlInterval
object to a value less than this interval.  This is
typically most important for the 'octets' counter in any
media-specific table.  For example, on an Ethernet
network, the etherHistoryOctets counter could overflow
in about one hour at the Ethernet's maximum
utilization.

This object may not be modified if the associated
historyControlStatus object is equal to valid(1).

The entity that configured this entry and is therefore
using the resources assigned to it.

The status of this historyControl entry.

Each instance of the media-specific table associated
with this historyControlEntry will be deleted by the agent
if this historyControlEntry is not equal to valid(1).

A list of Ethernet history entries.

An historical sample of Ethernet statistics on a particular
Ethernet interface.  This sample is associated with the
historyControlEntry which set up the parameters for
a regular collection of these samples.  As an example, an
instance of the etherHistoryPkts object might be named
etherHistoryPkts.2.89

The history of which this entry is a part.  The
history identified by a particular value of this
index is the same history as identified
by the same value of historyControlIndex.

An index that uniquely identifies the particular
sample this entry represents among all samples
associated with the same historyControlEntry.
This index starts at 1 and increases by one
as each new sample is taken.

The value of sysUpTime at the start of the interval
over which this sample was measured.  If the probe
keeps track of the time of day, it should start
the first sample of the history at a time such that
when the next hour of the day begins, a sample is
started at that instant.  Note that following this
rule may require the probe to delay collecting the
first sample of the history, as each sample must be
of the same interval.  Also note that the sample which
is currently being collected is not accessible in this
table until the end of its interval.

The total number of events in which packets
were dropped by the probe due to lack of resources
during this sampling interval.  Note that this number
is not necessarily the number of packets dropped, it
is just the number of times this condition has been


detected.

The total number of octets of data (including
those in bad packets) received on the
network (excluding framing bits but including
FCS octets).

The number of packets (including bad packets)
received during this sampling interval.

The number of good packets received during this
sampling interval that were directed to the
broadcast address.

The number of good packets received during this
sampling interval that were directed to a
multicast address.  Note that this number does not
include packets addressed to the broadcast address.

The number of packets received during this
sampling interval that had a length (excluding
framing bits but including FCS octets) between
64 and 1518 octets, inclusive, but had either a bad Frame
Check Sequence (FCS) with an integral number of octets
(FCS Error) or a bad FCS with a non-integral number
of octets (Alignment Error).

The number of packets received during this
sampling interval that were less than 64 octets
long (excluding framing bits but including FCS
octets) and were otherwise well formed.

The number of packets received during this
sampling interval that were longer than 1518
octets (excluding framing bits but including
FCS octets) but were otherwise well formed.

The total number of packets received during this
sampling interval that were less than 64 octets in
length (excluding framing bits but including FCS


octets) had either a bad Frame Check Sequence (FCS)
with an integral number of octets (FCS Error) or a bad
FCS with a non-integral number of octets (Alignment
Error).

Note that it is entirely normal for etherHistoryFragments to
increment.  This is because it counts both runts (which are
normal occurrences due to collisions) and noise hits.

The number of packets received during this
sampling interval that were longer than 1518 octets
(excluding framing bits but including FCS octets),
and  had either a bad Frame Check Sequence (FCS)
with an integral number of octets (FCS Error) or
a bad FCS with a non-integral number of octets
(Alignment Error).

Note that this definition of jabber is different
than the definition in IEEE-802.3 section 8.2.1.5
(10BASE5) and section 10.3.1.4 (10BASE2).  These
documents define jabber as the condition where any
packet exceeds 20 ms.  The allowed range to detect
jabber is between 20 ms and 150 ms.

The best estimate of the total number of collisions
on this Ethernet segment during this sampling
interval.

The value returned will depend on the location of the
RMON probe. Section 8.2.1.3 (10BASE-5) and section
10.3.1.3 (10BASE-2) of IEEE standard 802.3 states that a
station must detect a collision, in the receive mode, if
three or more stations are transmitting simultaneously.  A
repeater port must detect a collision when two or more


stations are transmitting simultaneously.  Thus a probe
placed on a repeater port could record more collisions
than a probe connected to a station on the same segment
would.

Probe location plays a much smaller role when considering
10BASE-T.  14.2.1.4 (10BASE-T) of IEEE standard 802.3
defines a collision as the simultaneous presence of signals
on the DO and RD circuits (transmitting and receiving
at the same time).  A 10BASE-T station can only detect
collisions when it is transmitting.  Thus probes placed on
a station and a repeater, should report the same number of
collisions.

Note also that an RMON probe inside a repeater should
ideally report collisions between the repeater and one or
more other hosts (transmit collisions as defined by IEEE
802.3k) plus receiver collisions observed on any coax
segments to which the repeater is connected.

The best estimate of the mean physical layer
network utilization on this interface during this
sampling interval, in hundredths of a percent.

A list of alarm entries.

A list of parameters that set up a periodic checking
for alarm conditions.  For example, an instance of the
alarmValue object might be named alarmValue.8

An index that uniquely identifies an entry in the
alarm table.  Each such entry defines a
diagnostic sample at a particular interval
for an object on the device.

The interval in seconds over which the data is
sampled and compared with the rising and falling
thresholds.  When setting this variable, care
should be taken in the case of deltaValue
sampling - the interval should be set short enough
that the sampled variable is very unlikely to
increase or decrease by more than 2^31 - 1 during
a single sampling interval.

This object may not be modified if the associated
alarmStatus object is equal to valid(1).

The object identifier of the particular variable to be
sampled.  Only variables that resolve to an ASN.1 primitive
type of INTEGER (INTEGER, Integer32, Counter32, Counter64,
Gauge, or TimeTicks) may be sampled.

Because SNMP access control is articulated entirely
in terms of the contents of MIB views, no access
control mechanism exists that can restrict the value of
this object to identify only those objects that exist
in a particular MIB view.  Because there is thus no
acceptable means of restricting the read access that
could be obtained through the alarm mechanism, the
probe must only grant write access to this object in


those views that have read access to all objects on
the probe.

During a set operation, if the supplied variable name is
not available in the selected MIB view, a badValue error
must be returned.  If at any time the variable name of
an established alarmEntry is no longer available in the
selected MIB view, the probe must change the status of
this alarmEntry to invalid(4).

This object may not be modified if the associated
alarmStatus object is equal to valid(1).

The method of sampling the selected variable and
calculating the value to be compared against the
thresholds.  If the value of this object is
absoluteValue(1), the value of the selected variable
will be compared directly with the thresholds at the
end of the sampling interval.  If the value of this
object is deltaValue(2), the value of the selected
variable at the last sample will be subtracted from
the current value, and the difference compared with
the thresholds.

This object may not be modified if the associated
alarmStatus object is equal to valid(1).

The value of the statistic during the last sampling
period.  For example, if the sample type is deltaValue,
this value will be the difference between the samples
at the beginning and end of the period.  If the sample
type is absoluteValue, this value will be the sampled
value at the end of the period.


This is the value that is compared with the rising and
falling thresholds.

The value during the current sampling period is not
made available until the period is completed and will
remain available until the next period completes.

The alarm that may be sent when this entry is first
set to valid.  If the first sample after this entry
becomes valid is greater than or equal to the
risingThreshold and alarmStartupAlarm is equal to
risingAlarm(1) or risingOrFallingAlarm(3), then a single
rising alarm will be generated.  If the first sample
after this entry becomes valid is less than or equal
to the fallingThreshold and alarmStartupAlarm is equal
to fallingAlarm(2) or risingOrFallingAlarm(3), then a
single falling alarm will be generated.

This object may not be modified if the associated
alarmStatus object is equal to valid(1).

A threshold for the sampled statistic.  When the current
sampled value is greater than or equal to this threshold,
and the value at the last sampling interval was less than
this threshold, a single event will be generated.
A single event will also be generated if the first
sample after this entry becomes valid is greater than or
equal to this threshold and the associated
alarmStartupAlarm is equal to risingAlarm(1) or
risingOrFallingAlarm(3).

After a rising event is generated, another such event


will not be generated until the sampled value
falls below this threshold and reaches the
alarmFallingThreshold.

This object may not be modified if the associated
alarmStatus object is equal to valid(1).

A threshold for the sampled statistic.  When the current
sampled value is less than or equal to this threshold,
and the value at the last sampling interval was greater than
this threshold, a single event will be generated.
A single event will also be generated if the first
sample after this entry becomes valid is less than or
equal to this threshold and the associated
alarmStartupAlarm is equal to fallingAlarm(2) or
risingOrFallingAlarm(3).

After a falling event is generated, another such event
will not be generated until the sampled value
rises above this threshold and reaches the
alarmRisingThreshold.

This object may not be modified if the associated
alarmStatus object is equal to valid(1).

The index of the eventEntry that is
used when a rising threshold is crossed.  The
eventEntry identified by a particular value of
this index is the same as identified by the same value
of the eventIndex object.  If there is no
corresponding entry in the eventTable, then
no association exists.  In particular, if this value
is zero, no associated event will be generated, as
zero is not a valid event index.

This object may not be modified if the associated


alarmStatus object is equal to valid(1).

The index of the eventEntry that is
used when a falling threshold is crossed.  The
eventEntry identified by a particular value of
this index is the same as identified by the same value
of the eventIndex object.  If there is no
corresponding entry in the eventTable, then
no association exists.  In particular, if this value
is zero, no associated event will be generated, as
zero is not a valid event index.

This object may not be modified if the associated
alarmStatus object is equal to valid(1).

The entity that configured this entry and is therefore
using the resources assigned to it.

The status of this alarm entry.

A list of host table control entries.

A list of parameters that set up the discovery of hosts
on a particular interface and the collection of statistics
about these hosts.  For example, an instance of the
hostControlTableSize object might be named
hostControlTableSize.1

An index that uniquely identifies an entry in the


hostControl table.  Each such entry defines
a function that discovers hosts on a particular interface
and places statistics about them in the hostTable and
the hostTimeTable on behalf of this hostControlEntry.

This object identifies the source of the data for
this instance of the host function.  This source
can be any interface on this device.  In order
to identify a particular interface, this object shall
identify the instance of the ifIndex object, defined
in RFC 2233 [17], for the desired interface.
For example, if an entry were to receive data from
interface #1, this object would be set to ifIndex.1.

The statistics in this group reflect all packets
on the local network segment attached to the identified
interface.

An agent may or may not be able to tell if fundamental
changes to the media of the interface have occurred and
necessitate an invalidation of this entry.  For example, a
hot-pluggable ethernet card could be pulled out and replaced
by a token-ring card.  In such a case, if the agent has such
knowledge of the change, it is recommended that it
invalidate this entry.

This object may not be modified if the associated
hostControlStatus object is equal to valid(1).

The number of hostEntries in the hostTable and the
hostTimeTable associated with this hostControlEntry.

The value of sysUpTime when the last entry
was deleted from the portion of the hostTable
associated with this hostControlEntry.  If no
deletions have occurred, this value shall be zero.

The entity that configured this entry and is therefore
using the resources assigned to it.

The status of this hostControl entry.

If this object is not equal to valid(1), all associated
entries in the hostTable, hostTimeTable, and the
hostTopNTable shall be deleted by the agent.

A list of host entries.

A collection of statistics for a particular host that has
been discovered on an interface of this device.  For example,
an instance of the hostOutBroadcastPkts object might be
named hostOutBroadcastPkts.1.6.8.0.32.27.3.176

The physical address of this host.

An index that defines the relative ordering of
the creation time of hosts captured for a
particular hostControlEntry.  This index shall
be between 1 and N, where N is the value of
the associated hostControlTableSize.  The ordering
of the indexes is based on the order of each entry's
insertion into the table, in which entries added earlier
have a lower index value than entries added later.

It is important to note that the order for a
particular entry may change as an (earlier) entry
is deleted from the table.  Because this order may
change, management stations should make use of the
hostControlLastDeleteTime variable in the
hostControlEntry associated with the relevant
portion of the hostTable.  By observing
this variable, the management station may detect
the circumstances where a previous association
between a value of hostCreationOrder
and a hostEntry may no longer hold.

The set of collected host statistics of which
this entry is a part.  The set of hosts
identified by a particular value of this
index is associated with the hostControlEntry
as identified by the same value of hostControlIndex.

The number of good packets transmitted to this
address since it was added to the hostTable.

The number of packets, including bad packets, transmitted
by this address since it was added to the hostTable.

The number of octets transmitted to this address since
it was added to the hostTable (excluding framing
bits but including FCS octets), except for those
octets in bad packets.

The number of octets transmitted by this address since
it was added to the hostTable (excluding framing
bits but including FCS octets), including those
octets in bad packets.

The number of bad packets transmitted by this address
since this host was added to the hostTable.

The number of good packets transmitted by this
address that were directed to the broadcast address
since this host was added to the hostTable.

The number of good packets transmitted by this
address that were directed to a multicast address
since this host was added to the hostTable.
Note that this number does not include packets
directed to the broadcast address.

A list of time-ordered host table entries.

A collection of statistics for a particular host that has
been discovered on an interface of this device.  This
collection includes the relative ordering of the creation
time of this object.  For example, an instance of the
hostTimeOutBroadcastPkts object might be named
hostTimeOutBroadcastPkts.1.687

The physical address of this host.

An index that uniquely identifies an entry in
the hostTime table among those entries associated
with the same hostControlEntry.  This index shall
be between 1 and N, where N is the value of


the associated hostControlTableSize.  The ordering
of the indexes is based on the order of each entry's
insertion into the table, in which entries added earlier
have a lower index value than entries added later.
Thus the management station has the ability to
learn of new entries added to this table without
downloading the entire table.

It is important to note that the index for a
particular entry may change as an (earlier) entry
is deleted from the table.  Because this order may
change, management stations should make use of the
hostControlLastDeleteTime variable in the
hostControlEntry associated with the relevant
portion of the hostTimeTable.  By observing
this variable, the management station may detect
the circumstances where a download of the table
may have missed entries, and where a previous
association between a value of hostTimeCreationOrder
and a hostTimeEntry may no longer hold.

The set of collected host statistics of which
this entry is a part.  The set of hosts
identified by a particular value of this
index is associated with the hostControlEntry
as identified by the same value of hostControlIndex.

The number of good packets transmitted to this
address since it was added to the hostTimeTable.

The number of packets, including bad packets, transmitted
by this address since it was added to the hostTimeTable.

The number of octets transmitted to this address since
it was added to the hostTimeTable (excluding framing
bits but including FCS octets), except for those
octets in bad packets.

The number of octets transmitted by this address since
it was added to the hostTimeTable (excluding framing
bits but including FCS octets), including those
octets in bad packets.

The number of bad packets transmitted by this address
since this host was added to the hostTimeTable.

The number of good packets transmitted by this
address that were directed to the broadcast address


since this host was added to the hostTimeTable.

The number of good packets transmitted by this
address that were directed to a multicast address
since this host was added to the hostTimeTable.
Note that this number does not include packets directed
to the broadcast address.

A list of top N host control entries.

A set of parameters that control the creation of a report
of the top N hosts according to several metrics.  For
example, an instance of the hostTopNDuration object might
be named hostTopNDuration.3

An index that uniquely identifies an entry
in the hostTopNControl table.  Each such
entry defines one top N report prepared for
one interface.

The host table for which a top N report will be prepared
on behalf of this entry.  The host table identified by a
particular value of this index is associated with the same
host table as identified by the same value of
hostIndex.

This object may not be modified if the associated
hostTopNStatus object is equal to valid(1).

The variable for each host that the hostTopNRate
variable is based upon.

This object may not be modified if the associated
hostTopNStatus object is equal to valid(1).

The number of seconds left in the report currently being
collected.  When this object is modified by the management
station, a new collection is started, possibly aborting
a currently running report.  The new value is used
as the requested duration of this report, which is
loaded into the associated hostTopNDuration object.

When this object is set to a non-zero value, any
associated hostTopNEntries shall be made
inaccessible by the monitor.  While the value of this
object is non-zero, it decrements by one per second until
it reaches zero.  During this time, all associated
hostTopNEntries shall remain inaccessible.  At the time
that this object decrements to zero, the report is made
accessible in the hostTopNTable.  Thus, the hostTopN
table needs to be created only at the end of the collection
interval.

The number of seconds that this report has collected
during the last sampling interval, or if this
report is currently being collected, the number
of seconds that this report is being collected
during this sampling interval.

When the associated hostTopNTimeRemaining object is set,
this object shall be set by the probe to the same value
and shall not be modified until the next time
the hostTopNTimeRemaining is set.

This value shall be zero if no reports have been
requested for this hostTopNControlEntry.

The maximum number of hosts requested for the top N
table.

When this object is created or modified, the probe
should set hostTopNGrantedSize as closely to this
object as is possible for the particular probe
implementation and available resources.

The maximum number of hosts in the top N table.

When the associated hostTopNRequestedSize object is
created or modified, the probe should set this
object as closely to the requested value as is possible
for the particular implementation and available


resources. The probe must not lower this value except
as a result of a set to the associated
hostTopNRequestedSize object.

Hosts with the highest value of hostTopNRate shall be
placed in this table in decreasing order of this rate
until there is no more room or until there are no more
hosts.

The value of sysUpTime when this top N report was
last started.  In other words, this is the time that
the associated hostTopNTimeRemaining object was
modified to start the requested report.

The entity that configured this entry and is therefore
using the resources assigned to it.

The status of this hostTopNControl entry.

If this object is not equal to valid(1), all associated
hostTopNEntries shall be deleted by the agent.

A list of top N host entries.

A set of statistics for a host that is part of a top N
report.  For example, an instance of the hostTopNRate
object might be named hostTopNRate.3.10

This object identifies the top N report of which
this entry is a part.  The set of hosts
identified by a particular value of this
object is part of the same report as identified
by the same value of the hostTopNControlIndex object.

An index that uniquely identifies an entry in
the hostTopN table among those in the same report.
This index is between 1 and N, where N is the
number of entries in this table.  Increasing values
of hostTopNIndex shall be assigned to entries with
decreasing values of hostTopNRate until index N
is assigned to the entry with the lowest value of
hostTopNRate or there are no more hostTopNEntries.

The physical address of this host.

The amount of change in the selected variable
during this sampling interval.  The selected
variable is this host's instance of the object
selected by hostTopNRateBase.

A list of information entries for the
traffic matrix on each interface.

Information about a traffic matrix on a particular


interface.  For example, an instance of the
matrixControlLastDeleteTime object might be named
matrixControlLastDeleteTime.1

An index that uniquely identifies an entry in the
matrixControl table.  Each such entry defines
a function that discovers conversations on a particular
interface and places statistics about them in the
matrixSDTable and the matrixDSTable on behalf of this
matrixControlEntry.

This object identifies the source of
the data from which this entry creates a traffic matrix.
This source can be any interface on this device.  In
order to identify a particular interface, this object
shall identify the instance of the ifIndex object,
defined in RFC 2233 [17], for the desired
interface.  For example, if an entry were to receive data
from interface #1, this object would be set to ifIndex.1.

The statistics in this group reflect all packets
on the local network segment attached to the identified
interface.

An agent may or may not be able to tell if fundamental
changes to the media of the interface have occurred and


necessitate an invalidation of this entry.  For example, a
hot-pluggable ethernet card could be pulled out and replaced
by a token-ring card.  In such a case, if the agent has such
knowledge of the change, it is recommended that it
invalidate this entry.

This object may not be modified if the associated
matrixControlStatus object is equal to valid(1).

The number of matrixSDEntries in the matrixSDTable
for this interface.  This must also be the value of
the number of entries in the matrixDSTable for this
interface.

The value of sysUpTime when the last entry
was deleted from the portion of the matrixSDTable
or matrixDSTable associated with this matrixControlEntry.
If no deletions have occurred, this value shall be
zero.

The entity that configured this entry and is therefore
using the resources assigned to it.

The status of this matrixControl entry.


If this object is not equal to valid(1), all associated
entries in the matrixSDTable and the matrixDSTable
shall be deleted by the agent.

A list of traffic matrix entries indexed by
source and destination MAC address.

A collection of statistics for communications between
two addresses on a particular interface.  For example,
an instance of the matrixSDPkts object might be named
matrixSDPkts.1.6.8.0.32.27.3.176.6.8.0.32.10.8.113

The source physical address.

The destination physical address.

The set of collected matrix statistics of which
this entry is a part.  The set of matrix statistics
identified by a particular value of this index
is associated with the same matrixControlEntry
as identified by the same value of matrixControlIndex.

The number of packets transmitted from the source
address to the destination address (this number includes
bad packets).

The number of octets (excluding framing bits but
including FCS octets) contained in all packets
transmitted from the source address to the
destination address.

The number of bad packets transmitted from
the source address to the destination address.

A list of traffic matrix entries indexed by
destination and source MAC address.

A collection of statistics for communications between
two addresses on a particular interface.  For example,
an instance of the matrixSDPkts object might be named
matrixSDPkts.1.6.8.0.32.10.8.113.6.8.0.32.27.3.176

The source physical address.

The destination physical address.

The set of collected matrix statistics of which
this entry is a part.  The set of matrix statistics
identified by a particular value of this index
is associated with the same matrixControlEntry
as identified by the same value of matrixControlIndex.

The number of packets transmitted from the source
address to the destination address (this number includes
bad packets).

The number of octets (excluding framing bits
but including FCS octets) contained in all packets
transmitted from the source address to the
destination address.

The number of bad packets transmitted from
the source address to the destination address.

A list of packet filter entries.

A set of parameters for a packet filter applied on a
particular interface.  As an example, an instance of the
filterPktData object might be named filterPktData.12

An index that uniquely identifies an entry
in the filter table.  Each such entry defines
one filter that is to be applied to every packet
received on an interface.

This object identifies the channel of which this filter
is a part.  The filters identified by a particular value
of this object are associated with the same channel as
identified by the same value of the channelIndex object.

The offset from the beginning of each packet where
a match of packet data will be attempted.  This offset
is measured from the point in the physical layer
packet after the framing bits, if any.  For example,
in an Ethernet frame, this point is at the beginning of
the destination MAC address.

This object may not be modified if the associated
filterStatus object is equal to valid(1).

The data that is to be matched with the input packet.
For each packet received, this filter and the accompanying
filterPktDataMask and filterPktDataNotMask will be
adjusted for the offset.  The only bits relevant to this
match algorithm are those that have the corresponding
filterPktDataMask bit equal to one.  The following three
rules are then applied to every packet:

(1) If the packet is too short and does not have data
    corresponding to part of the filterPktData, the packet
    will fail this data match.

(2) For each relevant bit from the packet with the
    corresponding filterPktDataNotMask bit set to zero, if
    the bit from the packet is not equal to the corresponding
    bit from the filterPktData, then the packet will fail
    this data match.

(3) If for every relevant bit from the packet with the
    corresponding filterPktDataNotMask bit set to one, the
    bit from the packet is equal to the corresponding bit
    from the filterPktData, then the packet will fail this
    data match.

Any packets that have not failed any of the three matches
above have passed this data match.  In particular, a zero
length filter will match any packet.

This object may not be modified if the associated
filterStatus object is equal to valid(1).

The mask that is applied to the match process.
After adjusting this mask for the offset, only those
bits in the received packet that correspond to bits set
in this mask are relevant for further processing by the


match algorithm.  The offset is applied to filterPktDataMask
in the same way it is applied to the filter.  For the
purposes of the matching algorithm, if the associated
filterPktData object is longer than this mask, this mask is
conceptually extended with '1' bits until it reaches the
length of the filterPktData object.

This object may not be modified if the associated
filterStatus object is equal to valid(1).

The inversion mask that is applied to the match
process.  After adjusting this mask for the offset,
those relevant bits in the received packet that correspond
to bits cleared in this mask must all be equal to their
corresponding bits in the filterPktData object for the packet
to be accepted.  In addition, at least one of those relevant
bits in the received packet that correspond to bits set in
this mask must be different to its corresponding bit in the
filterPktData object.

For the purposes of the matching algorithm, if the associated
filterPktData object is longer than this mask, this mask is
conceptually extended with '0' bits until it reaches the
length of the filterPktData object.

This object may not be modified if the associated
filterStatus object is equal to valid(1).

The status that is to be matched with the input packet.
The only bits relevant to this match algorithm are those that
have the corresponding filterPktStatusMask bit equal to one.
The following two rules are then applied to every packet:

(1) For each relevant bit from the packet status with the
    corresponding filterPktStatusNotMask bit set to zero, if
    the bit from the packet status is not equal to the


    corresponding bit from the filterPktStatus, then the
    packet will fail this status match.

(2) If for every relevant bit from the packet status with the
    corresponding filterPktStatusNotMask bit set to one, the
    bit from the packet status is equal to the corresponding
    bit from the filterPktStatus, then the packet will fail
    this status match.

Any packets that have not failed either of the two matches
above have passed this status match.  In particular, a zero
length status filter will match any packet's status.

The value of the packet status is a sum.  This sum
initially takes the value zero.  Then, for each
error, E, that has been discovered in this packet,
2 raised to a value representing E is added to the sum.
The errors and the bits that represent them are dependent
on the media type of the interface that this channel
is receiving packets from.

The errors defined for a packet captured off of an
Ethernet interface are as follows:

    bit #    Error
        0    Packet is longer than 1518 octets
        1    Packet is shorter than 64 octets
        2    Packet experienced a CRC or Alignment error

For example, an Ethernet fragment would have a
value of 6 (2^1 + 2^2).

As this MIB is expanded to new media types, this object
will have other media-specific errors defined.

For the purposes of this status matching algorithm, if the
packet status is longer than this filterPktStatus object,
this object is conceptually extended with '0' bits until it
reaches the size of the packet status.

This object may not be modified if the associated
filterStatus object is equal to valid(1).

The mask that is applied to the status match process.
Only those bits in the received packet that correspond to
bits set in this mask are relevant for further processing
by the status match algorithm.  For the purposes
of the matching algorithm, if the associated filterPktStatus
object is longer than this mask, this mask is conceptually
extended with '1' bits until it reaches the size of the
filterPktStatus.  In addition, if a packet status is longer
than this mask, this mask is conceptually extended with '0'
bits until it reaches the size of the packet status.

This object may not be modified if the associated
filterStatus object is equal to valid(1).

The inversion mask that is applied to the status match
process.  Those relevant bits in the received packet status
that correspond to bits cleared in this mask must all be
equal to their corresponding bits in the filterPktStatus
object for the packet to be accepted.  In addition, at least
one of those relevant bits in the received packet status
that correspond to bits set in this mask must be different
to its corresponding bit in the filterPktStatus object for
the packet to be accepted.

For the purposes of the matching algorithm, if the associated
filterPktStatus object or a packet status is longer than this
mask, this mask is conceptually extended with '0' bits until
it reaches the longer of the lengths of the filterPktStatus
object and the packet status.

This object may not be modified if the associated
filterStatus object is equal to valid(1).

The entity that configured this entry and is therefore
using the resources assigned to it.

The status of this filter entry.

A list of packet channel entries.

A set of parameters for a packet channel applied on a
particular interface.  As an example, an instance of the
channelMatches object might be named channelMatches.3

An index that uniquely identifies an entry in the channel
table.  Each such entry defines one channel, a logical
data and event stream.

It is suggested that before creating a channel, an
application should scan all instances of the
filterChannelIndex object to make sure that there are no
pre-existing filters that would be inadvertently be linked
to the channel.

The value of this object uniquely identifies the
interface on this remote network monitoring device to which
the associated filters are applied to allow data into this
channel.  The interface identified by a particular value
of this object is the same interface as identified by the
same value of the ifIndex object, defined in RFC 2233 [17].

The filters in this group are applied to all packets on
the local network segment attached to the identified
interface.

An agent may or may not be able to tell if fundamental
changes to the media of the interface have occurred and
necessitate an invalidation of this entry.  For example, a
hot-pluggable ethernet card could be pulled out and replaced
by a token-ring card.  In such a case, if the agent has such
knowledge of the change, it is recommended that it
invalidate this entry.

This object may not be modified if the associated
channelStatus object is equal to valid(1).

This object controls the action of the filters
associated with this channel.  If this object is equal
to acceptMatched(1), packets will be accepted to this
channel if they are accepted by both the packet data and
packet status matches of an associated filter.  If
this object is equal to acceptFailed(2), packets will
be accepted to this channel only if they fail either
the packet data match or the packet status match of
each of the associated filters.

In particular, a channel with no associated filters will
match no packets if set to acceptMatched(1) case and will
match all packets in the acceptFailed(2) case.

This object may not be modified if the associated
channelStatus object is equal to valid(1).

This object controls the flow of data through this channel.
If this object is on(1), data, status and events flow
through this channel.  If this object is off(2), data,
status and events will not flow through this channel.

The value of this object identifies the event
that is configured to turn the associated
channelDataControl from off to on when the event is
generated.  The event identified by a particular value
of this object is the same event as identified by the
same value of the eventIndex object.  If there is no
corresponding entry in the eventTable, then no
association exists.  In fact, if no event is intended
for this channel, channelTurnOnEventIndex must be
set to zero, a non-existent event index.


This object may not be modified if the associated
channelStatus object is equal to valid(1).

The value of this object identifies the event
that is configured to turn the associated
channelDataControl from on to off when the event is
generated.  The event identified by a particular value
of this object is the same event as identified by the
same value of the eventIndex object.  If there is no
corresponding entry in the eventTable, then no
association exists.  In fact, if no event is intended
for this channel, channelTurnOffEventIndex must be
set to zero, a non-existent event index.

This object may not be modified if the associated
channelStatus object is equal to valid(1).

The value of this object identifies the event
that is configured to be generated when the
associated channelDataControl is on and a packet
is matched.  The event identified by a particular value
of this object is the same event as identified by the
same value of the eventIndex object.  If there is no
corresponding entry in the eventTable, then no
association exists.  In fact, if no event is intended
for this channel, channelEventIndex must be
set to zero, a non-existent event index.

This object may not be modified if the associated
channelStatus object is equal to valid(1).

The event status of this channel.

If this channel is configured to generate events
when packets are matched, a means of controlling
the flow of those events is often needed.  When
this object is equal to eventReady(1), a single
event may be generated, after which this object
will be set by the probe to eventFired(2).  While
in the eventFired(2) state, no events will be
generated until the object is modified to
eventReady(1) (or eventAlwaysReady(3)).  The
management station can thus easily respond to a
notification of an event by re-enabling this object.

If the management station wishes to disable this
flow control and allow events to be generated
at will, this object may be set to
eventAlwaysReady(3).  Disabling the flow control
is discouraged as it can result in high network
traffic or other performance problems.

The number of times this channel has matched a packet.
Note that this object is updated even when
channelDataControl is set to off.

A comment describing this channel.

The entity that configured this entry and is therefore
using the resources assigned to it.

The status of this channel entry.

A list of buffers control entries.

A set of parameters that control the collection of a stream
of packets that have matched filters.  As an example, an
instance of the bufferControlCaptureSliceSize object might
be named bufferControlCaptureSliceSize.3

An index that uniquely identifies an entry
in the bufferControl table.  The value of this
index shall never be zero.  Each such
entry defines one set of packets that is
captured and controlled by one or more filters.