All MIBs › IEEE8021-CN-MIB
Organization: IEEE 802.1 Working Group
Last Updated: 2018-06-28
Category: Quality of Service, Standard: IEEE 802, Technology: Switching/L2
Description: IEEE 802.1 MIB for Congestion Notification (802.1Qau) managing quantized congestion notification in Ethernet networks.
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What Is IEEE8021-CN-MIB?
IEEE8021-CN-MIB is a vendor-neutral, standards-based MIB defined by IEEE 802.1Q for Congestion Notification (802.1Qau), a mechanism used in data center Ethernet networks to signal upstream congestion via Congestion Notification Messages (CNMs) so that traffic sources can throttle back before switch buffers overflow. It exposes global per-switch-component congestion-notification settings (master enable, CNM transmit priority, discarded-frame counts) and per-port error/priority tables identifying which ports and priorities are experiencing congestion. This is primarily a performance/fault-status MIB for network congestion, letting an administrator detect buffer-overflow-driven frame discards and identify which ports and traffic priorities are contributing to congestion in a data center fabric. It is defined as part of, and depends on, the IEEE 802.1Q bridging standard for its object model. It is typically deployed on data center Ethernet switches supporting Data Center Bridging (DCB) features such as CN, PFC, and ETS for lossless or low-loss fabric behavior. Engineers implementing or auditing this functionality typically reference the IEEE8021-CN-MIB RFC/standard documentation for the authoritative specification.
IPNetwork Monitor allows you to monitor SNMP objects defined in IEEE8021-CN-MIB. Use the built-in SNMP Monitoring Browser to explore available variables, view their current values and descriptions, and select the objects you want to monitor. You can then create SNMP monitors, configure thresholds, and receive alerts when monitored values change.
Supported Devices
- vendor-neutral, standards-based MIB, not tied to a specific manufacturer; applies to data center Ethernet switches supporting 802.1Qau Congestion Notification
Monitoring Examples
An administrator would poll ieee8021CnGlobalDiscardedFrames on ieee8021CnGlobalTable to detect rising frame-discard counts indicating congestion-driven drops on a switch component. Checking ieee8021CnErroredPortTable's ieee8021CnEpIfIndex and ieee8021CnEpPriority would identify which specific port and traffic priority class is triggering congestion notifications. A sudden increase in discarded frames combined with a specific priority consistently flagged in ieee8021CnErroredPortTable would point to an oversubscribed link or misconfigured priority-based flow control on that port.
What Can Be Monitored
- congestion notification enable status
- discarded frame counts
- errored ports by priority
- CNM transmit priority configuration
This MIB depends on
Related MIBs
Imported Objects
From IEEE8021-TC-MIB
| IEEE8021PbbComponentIdentifier | |
| IEEE8021PriorityValue | |
| ieee802dot1mibs | OBJECT-IDENTITY |
From IF-MIB
| InterfaceIndex | |
| ifGeneralInformationGroup | OBJECT-GROUP |
From LLDP-V2-TC-MIB
| LldpV2DestAddressTableIndex |
From SNMPv2-CONF
| MODULE-COMPLIANCE | |
| OBJECT-GROUP |
From SNMPv2-MIB
| systemGroup | OBJECT-GROUP |
From SNMPv2-SMI
| Counter32 | |
| Counter64 | |
| Integer32 | |
| MODULE-IDENTITY | |
| OBJECT-TYPE | |
| Unsigned32 |
From SNMPv2-TC
| MacAddress | |
| RowStatus | |
| TEXTUAL-CONVENTION | |
| TimeInterval | |
| TruthValue |
How to Use in IPNetwork Monitor
Example using ieee8021CnGlobalDiscardedFrames OID:
Select a data center Ethernet switch as the target host to create a monitor — the SNMP service should be up and running on it. Click New Monitor, then check SNMP Custom on the Favorites tab, click Next, and confirm the host. On the next page, click Select... to open the built-in SNMP MIB Browser and type ieee8021CnGlobalDiscardedFrames into the Find box to locate it in the OID tree, selecting the specific row/instance you want to monitor since this is a table column, then select it and click OK. The number of frames discarded from full CP queues, in spite of the efforts of congestion notification to avoid discards. On the monitor's Main parameters page you can set the target's SNMP port (default 161), credentials, polling interval, and other settings — see the SNMP Monitor help for details. On the State conditions and Alerting tabs, configure when the monitor should change state and trigger an alert; since this is a Counter64-type OID, Value bounds is the most useful condition here — trigger an alert if the counter increases between polls, since a rising count of errors, failures, or discards often points to a real underlying problem. Click Finish to create the monitor; you can adjust any parameter later.
OIDs
| OID symbolic | OID numeric | Type | Access | Description |
|---|---|---|---|---|
| ieee8021CnMib | 1.3.111.2.802.1.1.18 | Congestion notification module. Unless otherwise indicated, the references in this MIB module are to IEEE Std 802.1Q. Copyright (C) IEEE (2018). This version of this MIB module is part of IEEE Std 802.1Q; see the draft itself for full legal notices. | ||
| ieee8021CnMIBObjects | 1.3.111.2.802.1.1.18.1 | |||
| ieee8021CnGlobalTable | 1.3.111.2.802.1.1.18.1.1 | not-accessible | A table containing the global variables for each component of a Bridge or for an end station. A value of 1 is used in a Bridge or end station that does not have multiple components. The contents of this table SHALL be maintained across a restart of the system. | |
| ieee8021CnGlobalEntry | 1.3.111.2.802.1.1.18.1.1.1 | not-accessible | A list of objects pertaining to a whole Bridge component or end station. | |
| OID ieee8021CnGlobalComponentId | 1.3.111.2.802.1.1.18.1.1.1.1 | IEEE8021PbbComponentIdentifier | not-accessible | The Bridge component within the system to which the information in this ieee8021CnGlobalEntry applies. If the system is not a Bridge, or if only one component is present in the Bridge, then this variable (index) MUST be equal to 1. |
| T/F ieee8021CnGlobalMasterEnable | 1.3.111.2.802.1.1.18.1.1.1.2 | TruthValue | read-write | The state of the congestion notification feature on this Bridge component or system. If true, Congestion notification is enabled, and if false, congestion notification is disabled. |
| IEE ieee8021CnGlobalCnmTransmitPriority | 1.3.111.2.802.1.1.18.1.1.1.3 | IEEE8021PriorityValue | read-write | The priority to use for all Congestion Notification Messages transmitted by this Bridge component or end station. |
| C64 ieee8021CnGlobalDiscardedFramesEx | 1.3.111.2.802.1.1.18.1.1.1.4 | Counter64 | read-only | The number of frames discarded from full CP queues, in spite of the efforts of congestion notification to avoid discards. This object is incremented whenever any of the ieee8021CnCpDiscardedFrames objects on any Port or priority in this same component are incremented. Discontinuities in the value of this counter can occur at re-initialization of the management system, and at other times as indicated by the value of ifCounterDiscontinuityTime object of the associated interface (if any). |
| ieee8021CnErroredPortTable | 1.3.111.2.802.1.1.18.1.2 | not-accessible | There is one Errored Port Table per Bridge component or end station. It permits the retrieval of information about which interfaces have congestion notification configuration errors, namely, those specifying an alternate priority that is a CNPV. | |
| ieee8021CnErroredPortEntry | 1.3.111.2.802.1.1.18.1.2.1 | not-accessible | A list of interfaces whose ieee8021CnComPriAlternatePriority and/or ieee8021CnPortPriAlternatePriority specify a priority value that is a Congestion Notification Priority Value. | |
| OID ieee8021CnEpComponentId | 1.3.111.2.802.1.1.18.1.2.1.1 | IEEE8021PbbComponentIdentifier | not-accessible | The Bridge component within the system to which the information in this ieee8021CnErroredPortEntry applies. If the system is not a Bridge, or if only one component is present in the Bridge, then this variable (index) MUST be equal to 1. |
| IEE ieee8021CnEpPriority | 1.3.111.2.802.1.1.18.1.2.1.2 | IEEE8021PriorityValue | not-accessible | The priority value whose alternate priority is misconfigured. |
| NUM ieee8021CnEpIfIndex | 1.3.111.2.802.1.1.18.1.2.1.3 | InterfaceIndex | read-only | This object represents the Bridge Port or aggregated port on which the congestion notification alternate priority is misconfigured. Upon a restart of the system, the system SHALL, if necessary, change the value of this variable so that it references the row in the ifXTable with the same value of ifAlias that it referenced before the system restart. If no such row exists, then the system SHALL delete this row in the ieee8021CnErroredPortTable. |
| ieee8021CnCompntPriTable | 1.3.111.2.802.1.1.18.1.3 | not-accessible | Each row in this table supplies default values for one Congestion Notification Priority Value for a whole Bridge component or end station. Creating a row in this table makes the priority value of ieee8021CnComPriPriority a Congestion Notification Priority Value. Deleting a row in this table makes the value in the deleted ieee8021CnComPriPriority no longer a Congestion Notification Priority Value. A system SHALL NOT allow eight rows in this table to be created with the same value of ieee8021CnComPriComponentId; see the description of ieee8021CnComPriRowStatus. The contents of this table SHALL be maintained across a restart of the system. | |
| ieee8021CnCompntPriEntry | 1.3.111.2.802.1.1.18.1.3.1 | not-accessible | One entry per Congestion Notification Priority Value per Bridge component or end station. | |
| OID ieee8021CnComPriComponentId | 1.3.111.2.802.1.1.18.1.3.1.1 | IEEE8021PbbComponentIdentifier | not-accessible | The Bridge component within the system to which the information in this ieee8021CnCompntPriEntry applies. If the system is not a Bridge, or if only one component is present in the Bridge, then this variable (index) MUST be equal to 1. |
| IEE ieee8021CnComPriPriority | 1.3.111.2.802.1.1.18.1.3.1.2 | IEEE8021PriorityValue | not-accessible | The Congestion Notification Priority Value for which this row supplies default values. |
| IEE ieee8021CnComPriDefModeChoice | 1.3.111.2.802.1.1.18.1.3.1.3 | Ieee8021CnControlChoice | read-create | Specifies how the default CND defense mode and alternate priority for this Congestion Notification Priority Value on all ports on this Bridge component or end station are to be chosen, either: cpcAdmin(1) Default CND defense mode is chosen by ieee8021CnComPriAdminDefenseMode, and alternate priority by ieee8021CnComPriAlternatePriority. cpcAuto(2) Default CND defense mode is chosen by ieee8021CnPortPriAutoDefenseMode, and alternate priority by ieee8021CnComPriAutoAltPri. This variable can be overridden by ieee8021CnPortPriDefModeChoice. |
| IEE ieee8021CnComPriAlternatePriority | 1.3.111.2.802.1.1.18.1.3.1.4 | IEEE8021PriorityValue | read-create | The Congestion Notification Priority Value to which an incoming frame is to be mapped, in spite of what the Priority Regereration Table says, if 1) Congestion Notification is enabled and 2) the CND defense mode of the port is cptEdge. Deleting a row in this table does not alter the value of any other row's ieee8021CnComPriAlternatePriority. |
| IEE ieee8021CnComPriAutoAltPri | 1.3.111.2.802.1.1.18.1.3.1.5 | IEEE8021PriorityValue | read-only | The Congestion Notification Priority Value to which an incoming frame can be mapped, in spite of what the Priority Regereration Table says, if 1) Congestion Notification is enabled, 2) the CND defense mode of the port is cptEdge, and 3) ieee8021CnComPriDefModeChoice contains the value cpcAuto (2). The value of this object is the next lower priority value than this row's ieee8021CnComPriPriority that is not a CNPV, or the next higher non-CNPV, if all lower values are CNPVs. The value of this object, and any consequent priority regeneration, is automatically updated by the managed system whenever a row in the ieee8021CnCompntPriTable is created or deleted. The value of this object is not dependent upon whether congestion notification is enabled or disabled for any priority or for the whole Bridge component or end station; it depends only upon whether the ieee8021CnCompntPriTable row exists. |
| IEE ieee8021CnComPriAdminDefenseMode | 1.3.111.2.802.1.1.18.1.3.1.6 | Ieee8021CnDefenseMode | read-create | The default CND defense mode for this Congestion Notification Priority Value on all ports on this Bridge component or end station. This variable can be overridden by ieee8021CnPortPriAdminDefenseMode. |
| INT ieee8021CnComPriCreation | 1.3.111.2.802.1.1.18.1.3.1.7 | INTEGER | read-create | The default value for ieee8021CnComPriDefModeChoice for newly-created entries in the ieee8021CnPortPriTable: cncpAutoEnable (1) Newly-created ieee8021CnPortPriDefModeChoice objects take the value cpcComp (3). cncpAutoDisable(2) Newly-created ieee8021CnPortPriDefModeChoice objects take the value cpcAdmin (1). |
| IEE ieee8021CnComPriLldpInstanceChoice | 1.3.111.2.802.1.1.18.1.3.1.8 | Ieee8021CnLldpChoice | read-create | Specifies whether or not the default value for all Ports is to send and receive the Congestion Notification TLV in LLDPDUs, either: cnlNone(1) Do not send Congestion Notification TLVs, and ignore them on receipt. cnlAdmin(2) Use the LLDP instance selected by ieee8021CnComPriLldpInstanceSelector to send and receive the Congestion Notification TLV. This object can be overridden by ieee8021CnPortPriLldpInstanceChoice. |
| ADR ieee8021CnComPriLldpInstanceSelector | 1.3.111.2.802.1.1.18.1.3.1.9 | LldpV2DestAddressTableIndex | read-create | Specifies a default value for which LLDP instance is to be used to provide the information for automatic configuration of ports' CND defense modes (ieee8021CnPortPriAutoDefenseMode). This object is ignored by the managed system if ieee8021CnComPriLldpInstanceChoice contains the value cnlNone (1). This object can be overridden by ieee8021CnPortPriLldpInstanceChoice and ieee8021CnPortPriLldpInstanceChoice. |
| ROW ieee8021CnComPriRowStatus | 1.3.111.2.802.1.1.18.1.3.1.10 | RowStatus | read-create | This object indicates the status of an entry, and is used to create/delete entries. A system SHALL NOT permit eight ieee8021CnComPriRowStatus objects, all with the same value of ieee8021CnComPriComponentId, to have the value active(1). An attempt to create or activate a row when there are already seven active rows SHALL result in that eighth row's ieee8021CnComPriRowStatus having the value notReady(3), and the return of an inconsistentValue error. |
| ieee8021CnPortPriTable | 1.3.111.2.802.1.1.18.1.4 | not-accessible | Each row in this table supplies values for one port's Congestion Notification Priority Value (CNPV). Creating an entry in ieee8021CnCompntPriTable creates this entry, with the default values, on all ports in the Bridge component or end station. Deleting an entry in ieee8021CnCompntPriTable deletes this ieee8021CnCompntPriEntry on all ports in the Bridge component or end station. The contents of this table SHALL be maintained across a restart of the system, except as noted in the description of ieee8021CnPortPriIfIndex. | |
| ieee8021CnPortPriEntry | 1.3.111.2.802.1.1.18.1.4.1 | not-accessible | One entry per port per Congestion Notification Priority Value per Bridge component or end station. | |
| OID ieee8021CnPortPriComponentId | 1.3.111.2.802.1.1.18.1.4.1.1 | IEEE8021PbbComponentIdentifier | not-accessible | The Bridge component within the system to which the information in this ieee8021CnPortPriEntry applies. If the system is not a Bridge, or if only one component is present in the Bridge, then this variable (index) MUST be equal to 1. |
| IEE ieee8021CnPortPriority | 1.3.111.2.802.1.1.18.1.4.1.2 | IEEE8021PriorityValue | not-accessible | The Congestion Notification Priority Value for which this row supplies default values. |
| NUM ieee8021CnPortPriIfIndex | 1.3.111.2.802.1.1.18.1.4.1.3 | InterfaceIndex | not-accessible | This object represents the port or aggregated port to which the entry applies. Upon a restart of the system, the system SHALL, if necessary, change the value of this object, and rearrange the order of the ieee8021CnPortPriTable, so that the value in ieee8021CnPortPriIfIndex references the row in the ifXTable with the same value for ifAlias that it referenced before the system restart. If no such entry exists in the ifXTable, then the system SHALL delete the row in the ieee8021CnPortPriTable. |
| IEE ieee8021CnPortPriDefModeChoice | 1.3.111.2.802.1.1.18.1.4.1.4 | Ieee8021CnControlChoice | read-write | This object determines how the CND defense mode and alternate priority value of this port for this CNPV is to be selected, either: cpcAdmin(1) CND defense mode is controlled by ieee8021CnPortPriAdminDefenseMode, and alternate priority by ieee8021CnPortPriAlternatePriority. cpcAuto(2) CND defense mode is controlled by ieee8021CnPortPriAutoDefenseMode and alternate priority by ieee8021CnComPriAlternatePriority. cpcComp(3) CND defense mode and alternate priority are controlled by ieee8021CnComPriDefModeChoice. This variable can override ieee8021CnComPriDefModeChoice. |
| IEE ieee8021CnPortPriAdminDefenseMode | 1.3.111.2.802.1.1.18.1.4.1.5 | Ieee8021CnDefenseMode | read-write | This object indicates the operator's choice for the CND defense mode in which this port is to operate for this CNPV whenever ieee8021CnPortPriDefModeChoice has the value cpcAdmin(1). This variable can override ieee8021CnComPriDefModeChoice. |
| IEE ieee8021CnPortPriAutoDefenseMode | 1.3.111.2.802.1.1.18.1.4.1.6 | Ieee8021CnDefenseMode | read-only | This object indicates in which the CND defense mode this port would operate for this CNPV as determined by the LLDP Congestion Notification TLV. |
| IEE ieee8021CnPortPriLldpInstanceChoice | 1.3.111.2.802.1.1.18.1.4.1.7 | Ieee8021CnLldpChoice | read-write | Specifies how to determine the LLDP instance to be used for the Congestion Notification TLV, either: cnlNone(1) No LLDP Congestion Notification TLV is to carry Per-priority CNPV indicators or Per-priority Ready indicators on this Port for this priority. cnlAdmin(2) ieee8021CnPortPriLldpInstanceSelector governs which LLDP instance is to carry Per-priority CNPV indicators and Per-priority Ready indicators for this priority in its Congestion Notification TLV on this Port cnlComponent(3) ieee8021CnComPriLldpInstanceChoice governs LLDP instance selection for this Port and priority. This object can override ieee8021CnComPriLldpInstanceChoice. |
| ADR ieee8021CnPortPriLldpInstanceSelector | 1.3.111.2.802.1.1.18.1.4.1.8 | LldpV2DestAddressTableIndex | read-write | This object determines which LLDP instance selector, if any, is used for automatic determination of the CND defense mode for this port and CNPV. This object can override ieee8021CnComPriLldpInstanceSelector. |
| IEE ieee8021CnPortPriAlternatePriority | 1.3.111.2.802.1.1.18.1.4.1.9 | IEEE8021PriorityValue | read-write | The Congestion Notification Priority Value to which an incoming frame is to be mapped, in spite of what the Priority Regereration Table says, if 1) Congestion Notification is enabled and 2) the port is acting in the cptEdge (4) CND defense mode. This object is ignored unless ieee8021CnPortPriDefModeChoice contains the value cpcAdmin (1). |
| ieee8021CnCpTable | 1.3.111.2.802.1.1.18.1.5 | not-accessible | Each row in this table supplies values for one Congestion Point (CP). This table is indexed by component, port (interface), and an arbitrary CP index. This arbitrary CP index is not necessarily the Congestion Point Identifier (CPID) carried in Congestion Notification Messages (CNMs). Creating an entry in ieee8021CnCompntPriTable can create an entry in this table, with the default values, on all ports in the Bridge component or end station. Because more than one Congestion Notification Priority Value (CNPV) can flow through a single CP, the creation of an entry in ieee8021CnCompntPriTable does not necessarily create a new entry in this table. An end station can have more than one CP for the same CNPV, so creating an entry in ieee8021CnCompntPriTable can create multiple entries in this table. Because each port in a Bridge component or end station can have a different relationship between CNPVs and CPs, the entries created or deleted on each port can be different. Deleting the last entry in ieee8021CnCompntPriTable for a CNPV passing through the CP controlled by this entry deletes the entry on some or all of the ports in the Bridge component or end station. Because each port in a Bridge component or end station can have a different relationship between CNPVs and CPs, the entries created or deleted on each port can be different. The relationship between ieee8021CnCpIndex values and CPs is an implementation dependent matter. The contents of this table SHALL be maintained across a restart of the system, except as noted in the description of ieee8021CnCpIfIndex. | |
| ieee8021CnCpEntry | 1.3.111.2.802.1.1.18.1.5.1 | not-accessible | An entry in the Congestion Point table controls a single Congestion Point on a port in a Bridge component or end station. | |
| OID ieee8021CnCpComponentId | 1.3.111.2.802.1.1.18.1.5.1.1 | IEEE8021PbbComponentIdentifier | not-accessible | The Bridge component within the system to which the information in this ieee8021CnCpEntry applies. If the system is not a Bridge, or if only one component is present in the Bridge, then this variable (index) MUST be equal to 1. |
| NUM ieee8021CnCpIfIndex | 1.3.111.2.802.1.1.18.1.5.1.2 | InterfaceIndex | not-accessible | This object represents the port or aggregated port to which the entry applies. Upon a restart of the system, the system SHALL, if necessary, change the value of this object, and rearrange the order of the ieee8021CnCpTable, so that the value in ieee8021CnCpIfIndex references the row in the ifXTable with the same value for ifAlias that it referenced before the system restart. If no such entry exists in the ifXTable, then the system SHALL delete the row in the ieee8021CnCpTable. |
| U32 ieee8021CnCpIndex | 1.3.111.2.802.1.1.18.1.5.1.3 | Unsigned32 | not-accessible | This object is an arbitrary integer indexing the entries in this table among the entries for the same component and interface. In a system that supports no more than one Congestion Point per priority per interface, ieee8021CnCpIndex SHALL be equal to the lowest numerical Congestion Notification Priority Value served by this Congestion Point. Otherwise, it SHOULD be a small integer value. |
| IEE ieee8021CnCpPriority | 1.3.111.2.802.1.1.18.1.5.1.4 | IEEE8021PriorityValue | read-only | This object indicates the lowest numerical Congestion Notification Priority Value that this entry's Congestion Point serves. |
| MAC ieee8021CnCpMacAddress | 1.3.111.2.802.1.1.18.1.5.1.5 | MacAddress | read-only | This object indicates the MAC address used as the source address in Congestion Notification Message transmitted by this Congestion Point. |
| OCT ieee8021CnCpIdentifier | 1.3.111.2.802.1.1.18.1.5.1.6 | OCTET STRING | read-only | This object indicates the Congestion Point Identifier (CPID) transmitted in Congestion Notification Message by this Congestion Point. It is not specified whether the CPID reported in a CNM by a CP that serves multiple CNPVs does or does not have the same value for its different CNPVs. |
| U32 ieee8021CnCpQueueSizeSetPoint | 1.3.111.2.802.1.1.18.1.5.1.7 | Unsigned32 | read-write | This object is the set point for the queue managed by this Congestion Point (CP). Congestion Notification Messages are transmitted to the sources of frames queued in this CP's queue in order to keep the total number of octets stored in the queue at this set point. |
| I32 ieee8021CnCpFeedbackWeight | 1.3.111.2.802.1.1.18.1.5.1.8 | Integer32 | read-write | This object controls the weight (cpW) change in queue length in the calculation of cpFb when the Congestion Point is generating a Congestion Notification Message. The weight cpW is equal to two to the power of this object. Thus, if this object contains a -1, cpW = 1/2. |
| U32 ieee8021CnCpMinSampleBase | 1.3.111.2.802.1.1.18.1.5.1.9 | Unsigned32 | read-write | This object determines the minimum number of octets to enqueue in the Congestion Point's queue between transmissions of Congestion Notification Messages. |
| C64 ieee8021CnCpDiscardedFrames | 1.3.111.2.802.1.1.18.1.5.1.10 | Counter64 | read-only | The number of data frames discarded by the queue controlled by this Congestion Point due to queue congestion. Discontinuities in the value of this counter can occur at re-initialization of the management system, and at other times as indicated by the value of ifCounterDiscontinuityTime object of the associated interface (if any). |
| C64 ieee8021CnCpTransmittedFrames | 1.3.111.2.802.1.1.18.1.5.1.11 | Counter64 | read-only | The number of data frames passed on to the queue controlled by this Congestion Point that were not discarded due to queue congestion. Discontinuities in the value of this counter can occur at re-initialization of the management system, and at other times as indicated by the value of ifCounterDiscontinuityTime object of the associated interface (if any). |
| C64 ieee8021CnCpTransmittedCnms | 1.3.111.2.802.1.1.18.1.5.1.12 | Counter64 | read-only | The number of Congestion Notification Message transmitted by this Congestion Point. Discontinuities in the value of this counter can occur at re-initialization of the management system, and at other times as indicated by the value of ifCounterDiscontinuityTime object of the associated interface (if any). |
| U32 ieee8021CnCpMinHeaderOctets | 1.3.111.2.802.1.1.18.1.5.1.13 | Unsigned32 | read-write | Specifies the minimum number of octets to be returned in a Congestion Notification Message from the mac_service_data_unit of the data frame that triggered transmission of the CNM. If the mac_service_data_unit has fewer octets than the value of this object, then all of the mac_service_data_unit is returned in the CNM. |
| ieee8021CnCpidToInterfaceTable | 1.3.111.2.802.1.1.18.1.6 | not-accessible | This table allows the network manager to obtain the interface index and CP index needed to access an entry in the ieee8021CnCpTable, given a Congestion Point Identifier (CPID) received a Congestion Notification Messages (CNMs). Upon a restart of the system, the system SHALL, if necessary, update this table to be consistent with the ieee8021CnCpTable. | |
| ieee8021CnCpidToInterfaceEntry | 1.3.111.2.802.1.1.18.1.6.1 | not-accessible | An entry in the ieee8021CnCpidToInterfaceTable. Translates a Congestion Point Identifier to a component identifier, interface index, and CP index | |
| OCT ieee8021CnCpidToIfCpid | 1.3.111.2.802.1.1.18.1.6.1.1 | OCTET STRING | not-accessible | This object is the Congestion Point Identifier (CPID) transmitted in Congestion Notification Message by a Congestion Point residing in this Bridge component or end station. |
| OID ieee8021CnCpidToIfComponentId | 1.3.111.2.802.1.1.18.1.6.1.2 | IEEE8021PbbComponentIdentifier | read-only | The Bridge component within the system to which the information in this ieee8021CnCpidToInterfaceEntry applies. If the system is not a Bridge, or if only one component is present in the Bridge, then this variable (index) MUST be equal to 1. |
| NUM ieee8021CnCpidToIfIfIndex | 1.3.111.2.802.1.1.18.1.6.1.3 | InterfaceIndex | read-only | This object indicates the interface on which the selected Congestion Point resides. This value can be used, along with ieee8021CnCpidToIfCpIndex, to find the Congestion Point in the ieee8021CnCpTable. |
| U32 ieee8021CnCpidToIfCpIndex | 1.3.111.2.802.1.1.18.1.6.1.4 | Unsigned32 | read-only | This object indicates the Congestion Point's index on the interface on which the selected Congestion Point resides. This value can be used, along with ieee8021CnCpidToIfIfIndex, to find the Congestion Point in the ieee8021CnCpTable. |
| ieee8021CnRpPortPriTable | 1.3.111.2.802.1.1.18.1.7 | not-accessible | Each row in this table supplies values for all of the Reaction Points (RPs) on one Port and one priority of an end station or Bridge component. This table is indexed by component, port (interface), and priority. Creating an entry in ieee8021CnCompntPriTable can create an entry in this table, with the default values, on all ports in the end station. Deleting the an entry in ieee8021CnCompntPriTable for a CNPV passing through the RP controlled by this entry deletes entries on some or all of the ports in the end station. The contents of this table SHALL be maintained across a restart of the system, except as noted in the description of ieee8021CnRpPortPriIfIndex. | |
| ieee8021CnRpPortPriEntry | 1.3.111.2.802.1.1.18.1.7.1 | not-accessible | An entry in the Reaction Point table controls all of the Reaction Points on a port in an end station that share the same priority value. | |
| OID ieee8021CnRpPortPriComponentId | 1.3.111.2.802.1.1.18.1.7.1.1 | IEEE8021PbbComponentIdentifier | not-accessible | The Bridge component within the system to which the information in this ieee8021CnRpGroupEntry applies. If the system is not a Bridge, or if only one component is present in the Bridge, then this variable (index) MUST be equal to 1. |
| IEE ieee8021CnRpPortPriPriority | 1.3.111.2.802.1.1.18.1.7.1.2 | IEEE8021PriorityValue | not-accessible | This object indicates the lowest numerical Congestion Notification Priority Value that this entry's Reaction Point serves. |
| NUM ieee8021CnRpPortPriIfIndex | 1.3.111.2.802.1.1.18.1.7.1.3 | InterfaceIndex | not-accessible | This object indicates the interface on which the selected Reaction Points reside. Upon a restart of the system, the system SHALL, if necessary, change the value of this object, and rearrange the order of the ieee8021CnRpPortPriTable, so that the value in ieee8021CnRpPortPriIfIndex references the row in the ifXTable with the same value for ifAlias that it referenced before the system restart. If no such entry exists in the ifXTable, then the system SHALL delete the row in the ieee8021CnRpPortPriTable. |
| U32 ieee8021CnRpPortPriMaxRps | 1.3.111.2.802.1.1.18.1.7.1.4 | Unsigned32 | read-write | An integer controlling the maximum number of Reaction Points allowed for this CNPV on this Port. An end station SHALL not create more than this many Reaction Point on this Port, but it MAY create fewer. |
| C32 ieee8021CnRpPortPriCreatedRps | 1.3.111.2.802.1.1.18.1.7.1.5 | Counter32 | read-only | This object returns the number of times any of the Reaction Points (RPs) controlled by this entry has had its rpEnabled variable set TRUE by the reception of a Congestion Notification Message. Dividing the change in ieee8021CnRpPortPriCentiseconds by the change in this object over a time interval yields the average lifetime of an active RP during that interval. |
| C64 ieee8021CnRpPortPriCentiseconds | 1.3.111.2.802.1.1.18.1.7.1.6 | Counter64 | read-only | This object returns the total number of centi-seconds that any of the Reaction Points (RPs) controlled by this entry has had its rpEnabled variable in the TRUE state. That is, once each centi-second, this counter is incremented by the number of RPs this entry controls that are actively rate limiting output frames. Dividing the change in this object over a time interval by the length of the interval yields the average number of RPs active over that interval. Dividing the change in this object by the change in ieee8021CnRpPortPriCreatedRps over that same time interval yields the average lifetime of an active RP during that interval. |
| ieee8021CnRpGroupTable | 1.3.111.2.802.1.1.18.1.8 | not-accessible | Each row in this table supplies values for one or more Reaction Points (RPs). This table is indexed by component, port (interface), and an arbitrary RP index. Creating an entry in ieee8021CnCompntPriTable can create an entry in this table, with the default values, on all ports in the end station. An end station can have more than one RP for the same Congestion Notification Priority Value (CNPV), so creating an entry in ieee8021CnCompntPriTable can create multiple entries in this table. Because each port in a Bridge component or end station can have a different relationship between CNPVs and RPs, the entries created or deleted on each port can be different. Deleting the an entry in ieee8021CnCompntPriTable for a CNPV passing through the RP controlled by this entry deletes entries on some or all of the ports in the end station. Because each port in an end station can have a different relationship between CNPVs and RPs, the entries created or deleted on each port can be different. The relationship between ieee8021CnRpgIdentifier values and RPs is an implementation dependent matter. The contents of this table SHALL be maintained across a restart of the system, except as noted in the description of ieee8021CnRpgIfIndex. | |
| ieee8021CnRpGroupEntry | 1.3.111.2.802.1.1.18.1.8.1 | not-accessible | An entry in the Reaction Point table controls a group of Reaction Points, on a port in an end station. All of the Reaction Point controlled by this entry serve the same Congestion Notification Priority Value. | |
| OID ieee8021CnRpgComponentId | 1.3.111.2.802.1.1.18.1.8.1.1 | IEEE8021PbbComponentIdentifier | not-accessible | The Bridge component within the system to which the information in this ieee8021CnRpGroupEntry applies. If the system is not a Bridge, or if only one component is present in the Bridge, then this variable (index) MUST be equal to 1. |
| IEE ieee8021CnRpgPriority | 1.3.111.2.802.1.1.18.1.8.1.2 | IEEE8021PriorityValue | not-accessible | This object indicates the lowest numerical Congestion Notification Priority Value that this entry's Reaction Point serves. |
| NUM ieee8021CnRpgIfIndex | 1.3.111.2.802.1.1.18.1.8.1.3 | InterfaceIndex | not-accessible | This object indicates the interface on which the group of Reaction Points reside. Upon a restart of the system, the system SHALL, if necessary, change the value of this object, and rearrange the order of the ieee8021CnRpGroupTable, so that the value in ieee8021CnRpgIfIndex references the row in the ifXTable with the same value for ifAlias that it referenced before the system restart. If no such entry exists in the ifXTable, then the system SHALL delete the row in the ieee8021CnRpGroupTable. |
| U32 ieee8021CnRpgIdentifier | 1.3.111.2.802.1.1.18.1.8.1.4 | Unsigned32 | not-accessible | This object is an arbitrary integer indexing the entries in this table among the entries for the same interface. This index SHOULD, where possible, be equal to the Congestion Notification Priority Value served by this Reaction Point. |
| T/F ieee8021CnRpgEnable | 1.3.111.2.802.1.1.18.1.8.1.5 | TruthValue | read-write | Controls the rpEnabled variable of the Reaction Point state machines of the Reaction Points (RPs) controlled by this entry as follows: true(1) The rpEnabled variable for the RPs controlled by this object are not held in the FALSE state, thus enabling them to pay attention to received CNMs. false(2) The rpEnabled variable for the RPs controlled by this object are held in the FALSE state, thus disabling them from paying attention to received CNMs. |
| NUM ieee8021CnRpgTimeReset | 1.3.111.2.802.1.1.18.1.8.1.6 | TimeInterval | read-write | This object controls the value for all of the state machine variables, rpgTimeReset, used to reset the timers RpWhile. |
| U32 ieee8021CnRpgByteReset | 1.3.111.2.802.1.1.18.1.8.1.7 | Unsigned32 | read-write | This object controls the value for all of the state machine variables, rpgByteReset, used to reset the counters rpByteCount. |
| U32 ieee8021CnRpgThreshold | 1.3.111.2.802.1.1.18.1.8.1.8 | Unsigned32 | read-write | This object controls the number of times rpByteStage or rpTimeStage can count before the RP rate control state machine advances states. |
| U32 ieee8021CnRpgMaxRate | 1.3.111.2.802.1.1.18.1.8.1.9 | Unsigned32 | read-write | This object controls the maximum rate, in multiples of 1 Mb/s, at which an RP can transmit. Default value is the speed of the port. A system SHALL support a minimim value for this object that is no larger than 5 Mbits/s (object value 5). This rate includes all bits consequent to transmitting the frame on the LAN, including preamble, inter-frame gap, etc. |
| U32 ieee8021CnRpgAiRate | 1.3.111.2.802.1.1.18.1.8.1.10 | Unsigned32 | read-write | This object controls the transmission rate increment in the RPR_ACTIVE_INCREASE state (rpgAiRate) in multiples of 1 Mb/s. This rate includes all bits consequent to transmitting the frame on the LAN, including preamble, inter-frame gap, etc. |
| U32 ieee8021CnRpgHaiRate | 1.3.111.2.802.1.1.18.1.8.1.11 | Unsigned32 | read-write | This object controls the transmission rate increment in the RPR_HYPER_INCREASE state (rpgHaiRate) in multiples of 1 Mb/s. This rate includes all bits consequent to transmitting the frame on the LAN, including preamble, inter-frame gap, etc. |
| I32 ieee8021CnRpgGd | 1.3.111.2.802.1.1.18.1.8.1.12 | Integer32 | read-write | This object controls the number of bits that the value of the Quantized Feedback field received in a CNM PDU is shifted to the right to decrease rpTargetRate. rpgGd is thus 2 to the negative power of this object, e.g., 7 means rpgGd = 1/128. |
| U32 ieee8021CnRpgMinDecFac | 1.3.111.2.802.1.1.18.1.8.1.13 | Unsigned32 | read-write | This object controls the minimum factor by which the current RP transmit rate rpCurrentRate can be changed by reception of a Congestion Notification Message. Its integer value represents a percentage, from 1% to 100%. |
| U32 ieee8021CnRpgMinRate | 1.3.111.2.802.1.1.18.1.8.1.14 | Unsigned32 | read-write | This object controls the minimum transmission rate (rpgMinRate) in multiples of 1 Mb/s. A system SHALL support a value for this object that is no larger than 5 Mb/s per second. This rate includes all bits consequent to transmitting the frame on the LAN, including preamble, inter-frame gap, etc. |
| ieee8021CnConformance | 1.3.111.2.802.1.1.18.2 | |||
| ieee8021CnCompliances | 1.3.111.2.802.1.1.18.2.1 | |||
| ieee8021CnBridgeCompliance | 1.3.111.2.802.1.1.18.2.1.1 | The compliance statement for support by a Bridge of the IEEE8021-MIRP-MIB module. | ||
| ieee8021CnStationCompliance | 1.3.111.2.802.1.1.18.2.1.2 | The compliance statement for support by an end station of the IEEE8021-MIRP-MIB module. | ||
| ieee8021CnGroups | 1.3.111.2.802.1.1.18.2.2 | |||
| ieee8021CnGlobalReqdGroup | 1.3.111.2.802.1.1.18.2.2.1 | Objects in the global required group. | ||
| ieee8021CnCpGlobalGroup | 1.3.111.2.802.1.1.18.2.2.2 | Objects in the Congestion Point global group. | ||
| ieee8021CnCpidTranslateGroup | 1.3.111.2.802.1.1.18.2.2.3 | Objects in the CPID translate group. | ||
| ieee8021CnEplGroup | 1.3.111.2.802.1.1.18.2.2.4 | Objects for the Errored Ports Table group. | ||
| ieee8021CnComPriGroup | 1.3.111.2.802.1.1.18.2.2.5 | Objects for the global per-priority group. | ||
| ieee8021CnCpPriGroup | 1.3.111.2.802.1.1.18.2.2.6 | Objects for the Congestion Point per-priority group. | ||
| ieee8021CnGlobalPriPortGroup | 1.3.111.2.802.1.1.18.2.2.7 | Objects for the global per-priority per-port group. | ||
| ieee8021CnCpPriPortGroup | 1.3.111.2.802.1.1.18.2.2.8 | Objects for the Congestion Point per-priority per-port group. | ||
| ieee8021CnCpGroup | 1.3.111.2.802.1.1.18.2.2.9 | Objects for the Congestion Point group. | ||
| ieee8021CnRpppGroup | 1.3.111.2.802.1.1.18.2.2.10 | Objects for the Reaction Point per-Port per-priority group. | ||
| ieee8021CnRpGroup | 1.3.111.2.802.1.1.18.2.2.11 | Objects for the Reaction Point group. |
RFC description
IEEE 802.1Q congestion notification MIB for managing network congestion and traffic flow.
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