MPLS-LDP-STD-MIB

MplsLdpIdentifierThe LDP identifier is a six octet quantity which is used to identify a Label Switching Router (LSR) label space. The first four octets identify the LSR and must be a globally unique value, such as a 32-bit router ID assigned to the LSR, and the last two octets identify a specific label space within the LSR. SIZE (6) · OCTET STRING · hint 1d.1d.1d.1d:2d

Reference: RFC3036, LDP Specification, Section on LDP Identifiers.

The LDP identifier.

IndexIntegerAn integer which may be used as a table index. (1..4294967295) · Unsigned32 · hint d

This index is used as a secondary index to uniquely identify this row. Before creating a row in this table, the 'mplsLdpEntityIndexNext' object should be retrieved. That value should be used for the value of this index when creating a row in this table. NOTE: if a value of zero (0) is retrieved, that indicates that no rows can be created in this table at this time. A secondary index (this object) is meaningful to some but not all, LDP implementations. For example an LDP implementation which uses PPP would use this index to differentiate PPP sub-links. Another way to use this index is to give this the value of ifIndex. However, this is dependant on the implementation.

Unsigned32 (1..65535)

Reference: RFC3036, LDP Specification, Section 3.5.3 Initialization Message.

The version number of the LDP protocol which will be used in the session initialization message. Section 3.5.3 in the LDP Specification specifies that the version of the LDP protocol is negotiated during session establishment. The value of this object represents the value that is sent in the initialization message.

INTEGER1 = enable2 = disable · Integer32

The administrative status of this LDP Entity. If this object is changed from 'enable' to 'disable' and this entity has already attempted to establish contact with a Peer, then all contact with that Peer is lost and all information from that Peer needs to be removed from the MIB. (This implies that the network management subsystem should clean up any related entry in the mplsLdpPeerTable. This further implies that a 'tear-down' for that session is issued and the session and all information related to that session cease to exist). At this point the operator is able to change values which are related to this entity. When the admin status is set back to 'enable', then this Entity will attempt to establish a new session with the Peer.

INTEGER1 = unknown2 = enabled3 = disabled · Integer32

The operational status of this LDP Entity. The value of unknown(1) indicates that the operational status cannot be determined at this time. The value of unknown should be a transient condition before changing to enabled(2) or disabled(3).

InetPortNumberRepresents a 16 bit port number of an Internet transport layer protocol. Port numbers are assigned by IANA. A current list of all assignments is available from <http://www.iana.org/>. The value zero is object-specific and must be defined as part of the description of any object that uses this syntax. Examples of the usage of zero might include situations where a port number is unknown, or when the value zero is used as a wildcard in a filter.Reference: STD 6 (RFC 768), STD 7 (RFC 793) and RFC 2960 (0..65535) · Unsigned32 · hint d

Reference: RFC3036, LDP Specification, Section 3.10, Well-known Numbers, and Section 3.10.1. UDP and TCP Ports.

The TCP Port for LDP. The default value is the well-known value of this port.

InetPortNumberRepresents a 16 bit port number of an Internet transport layer protocol. Port numbers are assigned by IANA. A current list of all assignments is available from <http://www.iana.org/>. The value zero is object-specific and must be defined as part of the description of any object that uses this syntax. Examples of the usage of zero might include situations where a port number is unknown, or when the value zero is used as a wildcard in a filter.Reference: STD 6 (RFC 768), STD 7 (RFC 793) and RFC 2960 (0..65535) · Unsigned32 · hint d

Reference: RFC3036, LDP Specification, Section 2.4.1, Basic Discovery Mechanism, Section 2.4.2, Extended Discovery Mechanism, Section 3.10, Well-known Numbers, and Section 3.10.1. UDP and TCP Ports.

The UDP Discovery Port for LDP. The default value is the well-known value for this port.

Unsigned32 (256..65535) · octets

Reference: RFC3036, LDP Specification, Section 3.5.3. Initialization Message.

The maximum PDU Length that is sent in the Common Session Parameters of an Initialization Message. According to the LDP Specification [RFC3036] a value of 255 or less specifies the default maximum length of 4096 octets, this is why the value of this object starts at 256. The operator should explicitly choose the default value (i.e., 4096), or some other value. The receiving LSR MUST calculate the maximum PDU length for the session by using the smaller of its and its peer's proposals for Max PDU Length.

Unsigned32 (1..65535) · seconds

The 16-bit integer value which is the proposed keep alive hold timer for this LDP Entity.

Unsigned32 (0..65535) · seconds

Reference: RFC3036, LDP Specification, Section 3.5.2., Hello Message.

The 16-bit integer value which is the proposed Hello hold timer for this LDP Entity. The Hello Hold time in seconds. An LSR maintains a record of Hellos received from potential peers. This object represents the Hold Time in the Common Hello Parameters TLV of the Hello Message. A value of 0 is a default value and should be interpretted in conjunction with the mplsLdpEntityTargetPeer object. If the value of this object is 0: if the value of the mplsLdpEntityTargetPeer object is false(2), then this specifies that the Hold Time's actual default value is 15 seconds (i.e., the default Hold time for Link Hellos is 15 seconds). Otherwise if the value of the mplsLdpEntityTargetPeer object is true(1), then this specifies that the Hold Time's actual default value is 45 seconds (i.e., the default Hold time for Targeted Hellos is 45 seconds). A value of 65535 means infinite (i.e., wait forever). All other values represent the amount of time in seconds to wait for a Hello Message. Setting the hold time to a value smaller than 15 is not recommended, although not forbidden according to RFC3036.

Integer32 (0..100)

Reference: RFC3036, LDP Specification, Section 2.5.3 Session Initialization.

When attempting to establish a session with a given Peer, the given LDP Entity should send out the SNMP notification, 'mplsLdpInitSessionThresholdExceeded', when the number of Session Initialization messages sent exceeds this threshold. The notification is used to notify an operator when this Entity and its Peer are possibly engaged in an endless sequence of messages as each NAKs the other's Initialization messages with Error Notification messages. Setting this threshold which triggers the notification is one way to notify the operator. The notification should be generated each time this threshold is exceeded and for every subsequent Initialization message which is NAK'd with an Error Notification message after this threshold is exceeded. A value of 0 (zero) for this object indicates that the threshold is infinity, thus the SNMP notification will never be generated.

MplsLabelDistributionMethod1 = downstreamOnDemand2 = downstreamUnsolicitedThe label distribution method which is also called the label advertisement mode [RFC3036]. Each interface on an LSR is configured to operate in either Downstream Unsolicited or Downstream on Demand.Reference: Multiprotocol Label Switching Architecture, RFC3031. LDP Specification, RFC3036, Section 2.6.3. · Integer32

For any given LDP session, the method of label distribution must be specified.

MplsRetentionMode1 = conservative2 = liberalThe label retention mode which specifies whether an LSR maintains a label binding for a FEC learned from a neighbor that is not its next hop for the FEC. If the value is conservative(1) then advertised label mappings are retained only if they will be used to forward packets, i.e., if label came from a valid next hop. If the value is liberal(2) then all advertised label mappings are retained whether they are from a valid next hop or not.Reference: Multiprotocol Label Switching Architecture, RFC3031. LDP Specification, RFC3036, Section 2.6.2. · Integer32

The LDP Entity can be configured to use either conservative or liberal label retention mode. If the value of this object is conservative(1) then advertized label mappings are retained only if they will be used to forward packets, i.e., if label came from a valid next hop. If the value of this object is liberal(2) then all advertized label mappings are retained whether they are from a valid next hop or not.

Integer32 (0..255)

Reference: RFC3036, LDP Specification, Section 2.8 Loop Dection, Section 3.4.5 Path Vector TLV.

If the value of this object is 0 (zero) then Loop Detection for Path Vectors is disabled. Otherwise, if this object has a value greater than zero, then Loop Dection for Path Vectors is enabled, and the Path Vector Limit is this value. Also, the value of the object, 'mplsLdpLsrLoopDetectionCapable', must be set to either 'pathVector(4)' or 'hopCountAndPathVector(5)', if this object has a value greater than 0 (zero), otherwise it is ignored.

Integer32 (0..255)

If the value of this object is 0 (zero), then Loop Detection using Hop Counters is disabled. If the value of this object is greater than 0 (zero) then Loop Detection using Hop Counters is enabled, and this object specifies this Entity's maximum allowable value for the Hop Count. Also, the value of the object mplsLdpLsrLoopDetectionCapable must be set to either 'hopCount(3)' or 'hopCountAndPathVector(5)' if this object has a value greater than 0 (zero), otherwise it is ignored.

INTEGER1 = interface2 = loopback · Integer32

This specifies whether the loopback or interface address is to be used as the transport address in the transport address TLV of the hello message. If the value is interface(1), then the IP address of the interface from which hello messages are sent is used as the transport address in the hello message. Otherwise, if the value is loopback(2), then the IP address of the loopback interface is used as the transport address in the hello message.

TruthValue1 = true2 = falseRepresents a boolean value. · Integer32

If this LDP entity uses targeted peer then set this to true.

InetAddressType0 = unknown1 = ipv42 = ipv63 = ipv4z4 = ipv6z16 = dnsA value that represents a type of Internet address. unknown(0) An unknown address type. This value MUST be used if the value of the corresponding InetAddress object is a zero-length string. It may also be used to indicate an IP address that is not in one of the formats defined below. ipv4(1) An IPv4 address as defined by the InetAddressIPv4 textual convention. ipv6(2) An IPv6 address as defined by the InetAddressIPv6 textual convention. ipv4z(3) A non-global IPv4 address including a zone index as defined by the InetAddressIPv4z textual convention. ipv6z(4) A non-global IPv6 address including a zone index as defined by the InetAddressIPv6z textual convention. dns(16) A DNS domain name as defined by the InetAddressDNS textual convention. Each definition of a concrete InetAddressType value must be accompanied by a definition of a textual convention for use with that InetAddressType. To support future extensions, the InetAddressType textual convention SHOULD NOT be sub-typed in object type definitions. It MAY be sub-typed in compliance statements in order to require only a subset of these address types for a compliant implementation. Implementations must ensure that InetAddressType objects and any dependent objects (e.g., InetAddress objects) are consistent. An inconsistentValue error must be generated if an attempt to change an InetAddressType object would, for example, lead to an undefined InetAddress value. In particular, InetAddressType/InetAddress pairs must be changed together if the address type changes (e.g., from ipv6(2) to ipv4(1)). · Integer32

The type of the internetwork layer address used for the Extended Discovery. This object indicates how the value of mplsLdpEntityTargetPeerAddr is to be interpreted.

InetAddressDenotes a generic Internet address. An InetAddress value is always interpreted within the context of an InetAddressType value. Every usage of the InetAddress textual convention is required to specify the InetAddressType object that provides the context. It is suggested that the InetAddressType object be logically registered before the object(s) that use the InetAddress textual convention, if they appear in the same logical row. The value of an InetAddress object must always be consistent with the value of the associated InetAddressType object. Attempts to set an InetAddress object to a value inconsistent with the associated InetAddressType must fail with an inconsistentValue error. When this textual convention is used as the syntax of an index object, there may be issues with the limit of 128 sub-identifiers specified in SMIv2, STD 58. In this case, the object definition MUST include a 'SIZE' clause to limit the number of potential instance sub-identifiers; otherwise the applicable constraints MUST be stated in the appropriate conceptual row DESCRIPTION clauses, or in the surrounding documentation if there is no single DESCRIPTION clause that is appropriate. SIZE (0..255) · OCTET STRING

The value of the internetwork layer address used for the Extended Discovery. The value of mplsLdpEntityTargetPeerAddrType specifies how this address is to be interpreted.

MplsLdpLabelType1 = generic2 = atm3 = frameRelayThe Layer 2 label types which are defined for MPLS LDP and/or CR-LDP are generic(1), atm(2), or frameRelay(3). · Integer32

Reference: RFC3036, LDP Specification, Section 3.5.3., Initialization Message.

Specifies the optional parameters for the LDP Initialization Message. If the value is generic(1) then no optional parameters will be sent in the LDP Initialization message associated with this Entity. If the value is atmParameters(2) then a row must be created in the mplsLdpEntityAtmTable, which corresponds to this entry. If the value is frameRelayParameters(3) then a row must be created in the mplsLdpEntityFrameRelayTable, which corresponds to this entry.

TimeStampThe value of the sysUpTime object at which a specific occurrence happened. The specific occurrence must be defined in the description of any object defined using this type. If sysUpTime is reset to zero as a result of a re- initialization of the network management (sub)system, then the values of all TimeStamp objects are also reset. However, after approximately 497 days without a re- initialization, the sysUpTime object will reach 2^^32-1 and then increment around to zero; in this case, existing values of TimeStamp objects do not change. This can lead to ambiguities in the value of TimeStamp objects. · TimeTicks

The value of sysUpTime on the most recent occasion at which any one or more of this entity's counters suffered a discontinuity. The relevant counters are the specific instances associated with this entity of any Counter32 object contained in the 'mplsLdpEntityStatsTable'. If no such discontinuities have occurred since the last re-initialization of the local management subsystem, then this object contains a zero value.

StorageType1 = other2 = volatile3 = nonVolatile4 = permanent5 = readOnlyDescribes the memory realization of a conceptual row. A row which is volatile(2) is lost upon reboot. A row which is either nonVolatile(3), permanent(4) or readOnly(5), is backed up by stable storage. A row which is permanent(4) can be changed but not deleted. A row which is readOnly(5) cannot be changed nor deleted. If the value of an object with this syntax is either permanent(4) or readOnly(5), it cannot be written. Conversely, if the value is either other(1), volatile(2) or nonVolatile(3), it cannot be modified to be permanent(4) or readOnly(5). (All illegal modifications result in a 'wrongValue' error.) Every usage of this textual convention is required to specify the columnar objects which a permanent(4) row must at a minimum allow to be writable. · Integer32

The storage type for this conceptual row. Conceptual rows having the value 'permanent(4)' need not allow write-access to any columnar objects in the row.

RowStatus1 = active2 = notInService3 = notReady4 = createAndGo5 = createAndWait6 = destroyThe RowStatus textual convention is used to manage the creation and deletion of conceptual rows, and is used as the value of the SYNTAX clause for the status column of a conceptual row (as described in Section 7.7.1 of [2].) The status column has six defined values: - `active', which indicates that the conceptual row is available for use by the managed device; - `notInService', which indicates that the conceptual row exists in the agent, but is unavailable for use by the managed device (see NOTE below); 'notInService' has no implication regarding the internal consistency of the row, availability of resources, or consistency with the current state of the managed device; - `notReady', which indicates that the conceptual row exists in the agent, but is missing information necessary in order to be available for use by the managed device (i.e., one or more required columns in the conceptual row have not been instanciated); - `createAndGo', which is supplied by a management station wishing to create a new instance of a conceptual row and to have its status automatically set to active, making it available for use by the managed device; - `createAndWait', which is supplied by a management station wishing to create a new instance of a conceptual row (but not make it available for use by the managed device); and, - `destroy', which is supplied by a management station wishing to delete all of the instances associated with an existing conceptual row. Whereas five of the six values (all except `notReady') may be specified in a management protocol set operation, only three values will be returned in response to a management protocol retrieval operation: `notReady', `notInService' or `active'. That is, when queried, an existing conceptual row has only three states: it is either available for use by the managed device (the status column has value `active'); it is not available for use by the managed device, though the agent has sufficient information to attempt to make it so (the status column has value `notInService'); or, it is not available for use by the managed device, and an attempt to make it so would fail because the agent has insufficient information (the state column has value `notReady'). NOTE WELL This textual convention may be used for a MIB table, irrespective of whether the values of that table's conceptual rows are able to be modified while it is active, or whether its conceptual rows must be taken out of service in order to be modified. That is, it is the responsibility of the DESCRIPTION clause of the status column to specify whether the status column must not be `active' in order for the value of some other column of the same conceptual row to be modified. If such a specification is made, affected columns may be changed by an SNMP set PDU if the RowStatus would not be equal to `active' either immediately before or after processing the PDU. In other words, if the PDU also contained a varbind that would change the RowStatus value, the column in question may be changed if the RowStatus was not equal to `active' as the PDU was received, or if the varbind sets the status to a value other than 'active'. Also note that whenever any elements of a row exist, the RowStatus column must also exist. To summarize the effect of having a conceptual row with a status column having a SYNTAX clause value of RowStatus, consider the following state diagram: STATE +--------------+-----------+-------------+------------- | A | B | C | D | |status col.|status column| |status column | is | is |status column ACTION |does not exist| notReady | notInService| is active --------------+--------------+-----------+-------------+------------- set status |noError ->D|inconsist- |inconsistent-|inconsistent- column to | or | entValue| Value| Value createAndGo |inconsistent- | | | | Value| | | --------------+--------------+-----------+-------------+------------- set status |noError see 1|inconsist- |inconsistent-|inconsistent- column to | or | entValue| Value| Value createAndWait |wrongValue | | | --------------+--------------+-----------+-------------+------------- set status |inconsistent- |inconsist- |noError |noError column to | Value| entValue| | active | | | | | | or | | | | | | | |see 2 ->D|see 8 ->D| ->D --------------+--------------+-----------+-------------+------------- set status |inconsistent- |inconsist- |noError |noError ->C column to | Value| entValue| | notInService | | | | | | or | | or | | | | | |see 3 ->C| ->C|see 6 --------------+--------------+-----------+-------------+------------- set status |noError |noError |noError |noError ->A column to | | | | or destroy | ->A| ->A| ->A|see 7 --------------+--------------+-----------+-------------+------------- set any other |see 4 |noError |noError |see 5 column to some| | | | value | | see 1| ->C| ->D --------------+--------------+-----------+-------------+------------- (1) goto B or C, depending on information available to the agent. (2) if other variable bindings included in the same PDU, provide values for all columns which are missing but required, and all columns have acceptable values, then return noError and goto D. (3) if other variable bindings included in the same PDU, provide legal values for all columns which are missing but required, then return noError and goto C. (4) at the discretion of the agent, the return value may be either: inconsistentName: because the agent does not choose to create such an instance when the corresponding RowStatus instance does not exist, or inconsistentValue: if the supplied value is inconsistent with the state of some other MIB object's value, or noError: because the agent chooses to create the instance. If noError is returned, then the instance of the status column must also be created, and the new state is B or C, depending on the information available to the agent. If inconsistentName or inconsistentValue is returned, the row remains in state A. (5) depending on the MIB definition for the column/table, either noError or inconsistentValue may be returned. (6) the return value can indicate one of the following errors: wrongValue: because the agent does not support notInService (e.g., an agent which does not support createAndWait), or inconsistentValue: because the agent is unable to take the row out of service at this time, perhaps because it is in use and cannot be de-activated. (7) the return value can indicate the following error: inconsistentValue: because the agent is unable to remove the row at this time, perhaps because it is in use and cannot be de-activated. (8) the transition to D can fail, e.g., if the values of the conceptual row are inconsistent, then the error code would be inconsistentValue. NOTE: Other processing of (this and other varbinds of) the set request may result in a response other than noError being returned, e.g., wrongValue, noCreation, etc. Conceptual Row Creation There are four potential interactions when creating a conceptual row: selecting an instance-identifier which is not in use; creating the conceptual row; initializing any objects for which the agent does not supply a default; and, making the conceptual row available for use by the managed device. Interaction 1: Selecting an Instance-Identifier The algorithm used to select an instance-identifier varies for each conceptual row. In some cases, the instance- identifier is semantically significant, e.g., the destination address of a route, and a management station selects the instance-identifier according to the semantics. In other cases, the instance-identifier is used solely to distinguish conceptual rows, and a management station without specific knowledge of the conceptual row might examine the instances present in order to determine an unused instance-identifier. (This approach may be used, but it is often highly sub-optimal; however, it is also a questionable practice for a naive management station to attempt conceptual row creation.) Alternately, the MIB module which defines the conceptual row might provide one or more objects which provide assistance in determining an unused instance-identifier. For example, if the conceptual row is indexed by an integer-value, then an object having an integer-valued SYNTAX clause might be defined for such a purpose, allowing a management station to issue a management protocol retrieval operation. In order to avoid unnecessary collisions between competing management stations, `adjacent' retrievals of this object should be different. Finally, the management station could select a pseudo-random number to use as the index. In the event that this index was already in use and an inconsistentValue was returned in response to the management protocol set operation, the management station should simply select a new pseudo-random number and retry the operation. A MIB designer should choose between the two latter algorithms based on the size of the table (and therefore the efficiency of each algorithm). For tables in which a large number of entries are expected, it is recommended that a MIB object be defined that returns an acceptable index for creation. For tables with small numbers of entries, it is recommended that the latter pseudo-random index mechanism be used. Interaction 2: Creating the Conceptual Row Once an unused instance-identifier has been selected, the management station determines if it wishes to create and activate the conceptual row in one transaction or in a negotiated set of interactions. Interaction 2a: Creating and Activating the Conceptual Row The management station must first determine the column requirements, i.e., it must determine those columns for which it must or must not provide values. Depending on the complexity of the table and the management station's knowledge of the agent's capabilities, this determination can be made locally by the management station. Alternately, the management station issues a management protocol get operation to examine all columns in the conceptual row that it wishes to create. In response, for each column, there are three possible outcomes: - a value is returned, indicating that some other management station has already created this conceptual row. We return to interaction 1. - the exception `noSuchInstance' is returned, indicating that the agent implements the object-type associated with this column, and that this column in at least one conceptual row would be accessible in the MIB view used by the retrieval were it to exist. For those columns to which the agent provides read-create access, the `noSuchInstance' exception tells the management station that it should supply a value for this column when the conceptual row is to be created. - the exception `noSuchObject' is returned, indicating that the agent does not implement the object-type associated with this column or that there is no conceptual row for which this column would be accessible in the MIB view used by the retrieval. As such, the management station can not issue any management protocol set operations to create an instance of this column. Once the column requirements have been determined, a management protocol set operation is accordingly issued. This operation also sets the new instance of the status column to `createAndGo'. When the agent processes the set operation, it verifies that it has sufficient information to make the conceptual row available for use by the managed device. The information available to the agent is provided by two sources: the management protocol set operation which creates the conceptual row, and, implementation-specific defaults supplied by the agent (note that an agent must provide implementation-specific defaults for at least those objects which it implements as read-only). If there is sufficient information available, then the conceptual row is created, a `noError' response is returned, the status column is set to `active', and no further interactions are necessary (i.e., interactions 3 and 4 are skipped). If there is insufficient information, then the conceptual row is not created, and the set operation fails with an error of `inconsistentValue'. On this error, the management station can issue a management protocol retrieval operation to determine if this was because it failed to specify a value for a required column, or, because the selected instance of the status column already existed. In the latter case, we return to interaction 1. In the former case, the management station can re-issue the set operation with the additional information, or begin interaction 2 again using `createAndWait' in order to negotiate creation of the conceptual row. NOTE WELL Regardless of the method used to determine the column requirements, it is possible that the management station might deem a column necessary when, in fact, the agent will not allow that particular columnar instance to be created or written. In this case, the management protocol set operation will fail with an error such as `noCreation' or `notWritable'. In this case, the management station decides whether it needs to be able to set a value for that particular columnar instance. If not, the management station re-issues the management protocol set operation, but without setting a value for that particular columnar instance; otherwise, the management station aborts the row creation algorithm. Interaction 2b: Negotiating the Creation of the Conceptual Row The management station issues a management protocol set operation which sets the desired instance of the status column to `createAndWait'. If the agent is unwilling to process a request of this sort, the set operation fails with an error of `wrongValue'. (As a consequence, such an agent must be prepared to accept a single management protocol set operation, i.e., interaction 2a above, containing all of the columns indicated by its column requirements.) Otherwise, the conceptual row is created, a `noError' response is returned, and the status column is immediately set to either `notInService' or `notReady', depending on whether it has sufficient information to (attempt to) make the conceptual row available for use by the managed device. If there is sufficient information available, then the status column is set to `notInService'; otherwise, if there is insufficient information, then the status column is set to `notReady'. Regardless, we proceed to interaction 3. Interaction 3: Initializing non-defaulted Objects The management station must now determine the column requirements. It issues a management protocol get operation to examine all columns in the created conceptual row. In the response, for each column, there are three possible outcomes: - a value is returned, indicating that the agent implements the object-type associated with this column and had sufficient information to provide a value. For those columns to which the agent provides read-create access (and for which the agent allows their values to be changed after their creation), a value return tells the management station that it may issue additional management protocol set operations, if it desires, in order to change the value associated with this column. - the exception `noSuchInstance' is returned, indicating that the agent implements the object-type associated with this column, and that this column in at least one conceptual row would be accessible in the MIB view used by the retrieval were it to exist. However, the agent does not have sufficient information to provide a value, and until a value is provided, the conceptual row may not be made available for use by the managed device. For those columns to which the agent provides read-create access, the `noSuchInstance' exception tells the management station that it must issue additional management protocol set operations, in order to provide a value associated with this column. - the exception `noSuchObject' is returned, indicating that the agent does not implement the object-type associated with this column or that there is no conceptual row for which this column would be accessible in the MIB view used by the retrieval. As such, the management station can not issue any management protocol set operations to create an instance of this column. If the value associated with the status column is `notReady', then the management station must first deal with all `noSuchInstance' columns, if any. Having done so, the value of the status column becomes `notInService', and we proceed to interaction 4. Interaction 4: Making the Conceptual Row Available Once the management station is satisfied with the values associated with the columns of the conceptual row, it issues a management protocol set operation to set the status column to `active'. If the agent has sufficient information to make the conceptual row available for use by the managed device, the management protocol set operation succeeds (a `noError' response is returned). Otherwise, the management protocol set operation fails with an error of `inconsistentValue'. NOTE WELL A conceptual row having a status column with value `notInService' or `notReady' is unavailable to the managed device. As such, it is possible for the managed device to create its own instances during the time between the management protocol set operation which sets the status column to `createAndWait' and the management protocol set operation which sets the status column to `active'. In this case, when the management protocol set operation is issued to set the status column to `active', the values held in the agent supersede those used by the managed device. If the management station is prevented from setting the status column to `active' (e.g., due to management station or network failure) the conceptual row will be left in the `notInService' or `notReady' state, consuming resources indefinitely. The agent must detect conceptual rows that have been in either state for an abnormally long period of time and remove them. It is the responsibility of the DESCRIPTION clause of the status column to indicate what an abnormally long period of time would be. This period of time should be long enough to allow for human response time (including `think time') between the creation of the conceptual row and the setting of the status to `active'. In the absence of such information in the DESCRIPTION clause, it is suggested that this period be approximately 5 minutes in length. This removal action applies not only to newly-created rows, but also to previously active rows which are set to, and left in, the notInService state for a prolonged period exceeding that which is considered normal for such a conceptual row. Conceptual Row Suspension When a conceptual row is `active', the management station may issue a management protocol set operation which sets the instance of the status column to `notInService'. If the agent is unwilling to do so, the set operation fails with an error of `wrongValue' or `inconsistentValue'. Otherwise, the conceptual row is taken out of service, and a `noError' response is returned. It is the responsibility of the DESCRIPTION clause of the status column to indicate under what circumstances the status column should be taken out of service (e.g., in order for the value of some other column of the same conceptual row to be modified). Conceptual Row Deletion For deletion of conceptual rows, a management protocol set operation is issued which sets the instance of the status column to `destroy'. This request may be made regardless of the current value of the status column (e.g., it is possible to delete conceptual rows which are either `notReady', `notInService' or `active'.) If the operation succeeds, then all instances associated with the conceptual row are immediately removed. · Integer32

The status of this conceptual row. All writable objects in this row may be modified at any time, however, as described in detail in the section entitled, 'Changing Values After Session Establishment', and again described in the DESCRIPTION clause of the mplsLdpEntityAdminStatus object, if a session has been initiated with a Peer, changing objects in this table will wreak havoc with the session and interrupt traffic. To repeat again: the recommended procedure is to set the mplsLdpEntityAdminStatus to down, thereby explicitly causing a session to be torn down. Then, change objects in this entry, then set the mplsLdpEntityAdminStatus to enable, which enables a new session to be initiated.

Counter32

A count of the Session Initialization messages which were sent or received by this LDP Entity and were NAK'd. In other words, this counter counts the number of session initializations that failed. 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 mplsLdpEntityDiscontinuityTime.

Counter32

A count of the Session Rejected/No Hello Error Notification Messages sent or received by this LDP Entity. 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 mplsLdpEntityDiscontinuityTime.

Counter32

A count of the Session Rejected/Parameters Advertisement Mode Error Notification Messages sent or received by this LDP Entity. 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 mplsLdpEntityDiscontinuityTime.

Counter32

A count of the Session Rejected/Parameters Max Pdu Length Error Notification Messages sent or received by this LDP Entity. 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 mplsLdpEntityDiscontinuityTime.

Counter32

A count of the Session Rejected/Parameters Label Range Notification Messages sent or received by this LDP Entity. 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 mplsLdpEntityDiscontinuityTime.

Counter32

Reference: RFC3036, LDP Specification, Section 3.5.1.2.

This object counts the number of Bad LDP Identifier Fatal Errors detected by the session(s) (past and present) associated with this LDP Entity. 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 mplsLdpEntityDiscontinuityTime.

Counter32

Reference: RFC3036, LDP Specification, Section 3.5.1.2.

This object counts the number of Bad PDU Length Fatal Errors detected by the session(s) (past and present) associated with this LDP Entity. 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 mplsLdpEntityDiscontinuityTime.

Counter32

Reference: RFC3036, LDP Specification, Section 3.5.1.2.

This object counts the number of Bad Message Length Fatal Errors detected by the session(s) (past and present) associated with this LDP Entity. 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 mplsLdpEntityDiscontinuityTime.

Counter32

Reference: RFC3036, LDP Specification, Section 3.5.1.2.

This object counts the number of Bad TLV Length Fatal Errors detected by the session(s) (past and present) associated with this LDP Entity. 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 mplsLdpEntityDiscontinuityTime.

Counter32

Reference: RFC3036, LDP Specification, Section 3.5.1.2.

This object counts the number of Malformed TLV Value Fatal Errors detected by the session(s) (past and present) associated with this LDP Entity. 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 mplsLdpEntityDiscontinuityTime.

Counter32

Reference: RFC3036, LDP Specification, Section 3.5.1.2.

This object counts the number of Session Keep Alive Timer Expired Errors detected by the session(s) (past and present) associated with this LDP Entity. 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 mplsLdpEntityDiscontinuityTime.

Counter32

This object counts the number of Shutdown Notifications received related to session(s) (past and present) associated with this LDP Entity. 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 mplsLdpEntityDiscontinuityTime.

Counter32

This object counts the number of Shutdown Notfications sent related to session(s) (past and present) associated with this LDP Entity. 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 mplsLdpEntityDiscontinuityTime.

MplsLdpIdentifierThe LDP identifier is a six octet quantity which is used to identify a Label Switching Router (LSR) label space. The first four octets identify the LSR and must be a globally unique value, such as a 32-bit router ID assigned to the LSR, and the last two octets identify a specific label space within the LSR. SIZE (6) · OCTET STRING · hint 1d.1d.1d.1d:2d

The LDP identifier of this LDP Peer.

MplsLabelDistributionMethod1 = downstreamOnDemand2 = downstreamUnsolicitedThe label distribution method which is also called the label advertisement mode [RFC3036]. Each interface on an LSR is configured to operate in either Downstream Unsolicited or Downstream on Demand.Reference: Multiprotocol Label Switching Architecture, RFC3031. LDP Specification, RFC3036, Section 2.6.3. · Integer32

For any given LDP session, the method of label distribution must be specified.

Integer32 (0..255)

Reference: RFC3036, LDP Specification, Section 2.8 Loop Dection, Section 3.4.5 Path Vector TLV.

If the value of this object is 0 (zero) then Loop Dection for Path Vectors for this Peer is disabled. Otherwise, if this object has a value greater than zero, then Loop Dection for Path Vectors for this Peer is enabled and the Path Vector Limit is this value.

InetAddressType0 = unknown1 = ipv42 = ipv63 = ipv4z4 = ipv6z16 = dnsA value that represents a type of Internet address. unknown(0) An unknown address type. This value MUST be used if the value of the corresponding InetAddress object is a zero-length string. It may also be used to indicate an IP address that is not in one of the formats defined below. ipv4(1) An IPv4 address as defined by the InetAddressIPv4 textual convention. ipv6(2) An IPv6 address as defined by the InetAddressIPv6 textual convention. ipv4z(3) A non-global IPv4 address including a zone index as defined by the InetAddressIPv4z textual convention. ipv6z(4) A non-global IPv6 address including a zone index as defined by the InetAddressIPv6z textual convention. dns(16) A DNS domain name as defined by the InetAddressDNS textual convention. Each definition of a concrete InetAddressType value must be accompanied by a definition of a textual convention for use with that InetAddressType. To support future extensions, the InetAddressType textual convention SHOULD NOT be sub-typed in object type definitions. It MAY be sub-typed in compliance statements in order to require only a subset of these address types for a compliant implementation. Implementations must ensure that InetAddressType objects and any dependent objects (e.g., InetAddress objects) are consistent. An inconsistentValue error must be generated if an attempt to change an InetAddressType object would, for example, lead to an undefined InetAddress value. In particular, InetAddressType/InetAddress pairs must be changed together if the address type changes (e.g., from ipv6(2) to ipv4(1)). · Integer32

Reference: RFC3036, LDP Specification, Section 2.5.2 Transport Connection Establishment and Section 3.5.2.1 Hello Message Procedures.

The type of the Internet address for the mplsLdpPeerTransportAddr object. The LDP specification describes this as being either an IPv4 Transport Address or IPv6 Transport Address which is used in opening the LDP session's TCP connection, or if the optional TLV is not present, then this is the IPv4/IPv6 source address for the UPD packet carrying the Hellos. This object specifies how the value of the mplsLdpPeerTransportAddr object should be interpreted.

InetAddressDenotes a generic Internet address. An InetAddress value is always interpreted within the context of an InetAddressType value. Every usage of the InetAddress textual convention is required to specify the InetAddressType object that provides the context. It is suggested that the InetAddressType object be logically registered before the object(s) that use the InetAddress textual convention, if they appear in the same logical row. The value of an InetAddress object must always be consistent with the value of the associated InetAddressType object. Attempts to set an InetAddress object to a value inconsistent with the associated InetAddressType must fail with an inconsistentValue error. When this textual convention is used as the syntax of an index object, there may be issues with the limit of 128 sub-identifiers specified in SMIv2, STD 58. In this case, the object definition MUST include a 'SIZE' clause to limit the number of potential instance sub-identifiers; otherwise the applicable constraints MUST be stated in the appropriate conceptual row DESCRIPTION clauses, or in the surrounding documentation if there is no single DESCRIPTION clause that is appropriate. SIZE (0..255) · OCTET STRING

Reference: RFC3036, LDP Specification, Section 2.5.2 Transport Connection Establishment and Section 3.5.2.1 Hello Message Procedures.

The Internet address advertised by the peer in the Hello Message or the Hello source address. The type of this address is specified by the value of the mplsLdpPeerTransportAddrType object.

TimeStampThe value of the sysUpTime object at which a specific occurrence happened. The specific occurrence must be defined in the description of any object defined using this type. If sysUpTime is reset to zero as a result of a re- initialization of the network management (sub)system, then the values of all TimeStamp objects are also reset. However, after approximately 497 days without a re- initialization, the sysUpTime object will reach 2^^32-1 and then increment around to zero; in this case, existing values of TimeStamp objects do not change. This can lead to ambiguities in the value of TimeStamp objects. · TimeTicks

The value of sysUpTime at the time this Session entered its current state as denoted by the mplsLdpSessionState object.

INTEGER1 = nonexistent2 = initialized3 = openrec4 = opensent5 = operational · Integer32

Reference: RFC3036, LDP Specification, Section 2.5.4, Initialization State Machine.

The current state of the session, all of the states 1 to 5 are based on the state machine for session negotiation behavior.

INTEGER1 = unknown2 = active3 = passive · Integer32

Reference: RFC3036, LDP Specification, Section 2.5.3., Session Initialization

During session establishment the LSR/LER takes either the active role or the passive role based on address comparisons. This object indicates whether this LSR/LER was behaving in an active role or passive role during this session's establishment. The value of unknown(1), indicates that the role is not able to be determined at the present time.

Unsigned32 (1..65535)

Reference: RFC3036, LDP Specification, Section 3.5.3, Initialization Message.

The version of the LDP Protocol which this session is using. This is the version of the LDP protocol which has been negotiated during session initialization.

TimeIntervalA period of time, measured in units of 0.01 seconds. (0..2147483647) · Integer32

The keep alive hold time remaining for this session.

Unsigned32 (1..65535) · seconds

Reference: RFC3036, LDP Specification, Section 3.5.3, Initialization Message.

The negotiated KeepAlive Time which represents the amount of seconds between keep alive messages. The mplsLdpEntityKeepAliveHoldTimer related to this Session is the value that was proposed as the KeepAlive Time for this session. This value is negotiated during session initialization between the entity's proposed value (i.e., the value configured in mplsLdpEntityKeepAliveHoldTimer) and the peer's proposed KeepAlive Hold Timer value. This value is the smaller of the two proposed values.

Unsigned32 (1..65535) · octets

Reference: RFC3036, LDP Specification, Section 3.5.3, Initialization Message.

The value of maximum allowable length for LDP PDUs for this session. This value may have been negotiated during the Session Initialization. This object is related to the mplsLdpEntityMaxPduLength object. The mplsLdpEntityMaxPduLength object specifies the requested LDP PDU length, and this object reflects the negotiated LDP PDU length between the Entity and the Peer.

TimeStampThe value of the sysUpTime object at which a specific occurrence happened. The specific occurrence must be defined in the description of any object defined using this type. If sysUpTime is reset to zero as a result of a re- initialization of the network management (sub)system, then the values of all TimeStamp objects are also reset. However, after approximately 497 days without a re- initialization, the sysUpTime object will reach 2^^32-1 and then increment around to zero; in this case, existing values of TimeStamp objects do not change. This can lead to ambiguities in the value of TimeStamp objects. · TimeTicks

The value of sysUpTime on the most recent occasion at which any one or more of this session's counters suffered a discontinuity. The relevant counters are the specific instances associated with this session of any Counter32 object contained in the mplsLdpSessionStatsTable. The initial value of this object is the value of sysUpTime when the entry was created in this table. Also, a command generator can distinguish when a session between a given Entity and Peer goes away and a new session is established. This value would change and thus indicate to the command generator that this is a different session.

Counter32

This object counts the number of Unknown Message Type Errors detected by this LSR/LER during this session. 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 mplsLdpSessionDiscontinuityTime.

Counter32

This object counts the number of Unknown TLV Errors detected by this LSR/LER during this session. 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 mplsLdpSessionDiscontinuityTime.

Unsigned32 (1..4294967295)

An identifier for this specific adjacency.

TimeIntervalA period of time, measured in units of 0.01 seconds. (0..2147483647) · Integer32 · seconds

If the value of this object is 65535, this means that the hold time is infinite (i.e., wait forever). Otherwise, the time remaining for this Hello Adjacency to receive its next Hello Message. This interval will change when the 'next' Hello Message which corresponds to this Hello Adjacency is received unless it is infinite.

Unsigned32 (0..65535)

Reference: RFC3036, LDP Specification, Section 3.5.2 Hello Message

The Hello hold time which is negotiated between the Entity and the Peer. The entity associated with this Hello Adjacency issues a proposed Hello Hold Time value in the mplsLdpEntityHelloHoldTimer object. The peer also proposes a value and this object represents the negotiated value. A value of 0 means the default, which is 15 seconds for Link Hellos and 45 seconds for Targeted Hellos. A value of 65535 indicates an infinite hold time.

INTEGER1 = link2 = targeted · Integer32

This adjacency is the result of a 'link' hello if the value of this object is link(1). Otherwise, it is a result of a 'targeted' hello, targeted(2).

MplsIndexTypeThis is an octet string that can be used as a table index in cases where a large addressable space is required such as on an LSR where many applications may be provisioning labels. Note that the string containing the single octet with the value 0x00 is a reserved value used to represent special cases. When this TEXTUAL-CONVENTION is used as the SYNTAX of an object, the DESCRIPTION clause MUST specify if this special value is valid and if so what the special meaning is. In systems that provide write access to the MPLS-LSR-STD MIB, mplsIndexType SHOULD be used as a simple multi-digit integer encoded as an octet string. No further overloading of the meaning of an index SHOULD be made. In systems that do not offer write access to the MPLS-LSR-STD MIB, the mplsIndexType may contain implicit formatting that is specific to the implementation to convey additional information such as interface index, physical card or device, or application id. The interpretation of this additional formatting is implementation dependent and not covered in this document. Such formatting MUST NOT impact the basic functionality of read-only access to the MPLS-LSR-STD MIB by management applications that are not aware of the formatting rules. SIZE (1..24) · OCTET STRING

This contains the same value as the mplsInSegmentIndex in the MPLS-LSR-STD-MIB's mplsInSegmentTable.

MplsLdpLabelType1 = generic2 = atm3 = frameRelayThe Layer 2 label types which are defined for MPLS LDP and/or CR-LDP are generic(1), atm(2), or frameRelay(3). · Integer32

The Layer 2 Label Type.

MplsLspType1 = unknown2 = terminatingLsp3 = originatingLsp4 = crossConnectingLspTypes of Label Switch Paths (LSPs) on a Label Switching Router (LSR) or a Label Edge Router (LER) are: unknown(1) -- if the LSP is not known to be one of the following. terminatingLsp(2) -- if the LSP terminates on the LSR/LER, then this is an egressing LSP which ends on the LSR/LER, originatingLsp(3) -- if the LSP originates from this LSR/LER, then this is an ingressing LSP which is the head-end of the LSP, crossConnectingLsp(4) -- if the LSP ingresses and egresses on the LSR, then it is cross-connecting on that LSR. · Integer32

The type of LSP connection.

MplsIndexTypeThis is an octet string that can be used as a table index in cases where a large addressable space is required such as on an LSR where many applications may be provisioning labels. Note that the string containing the single octet with the value 0x00 is a reserved value used to represent special cases. When this TEXTUAL-CONVENTION is used as the SYNTAX of an object, the DESCRIPTION clause MUST specify if this special value is valid and if so what the special meaning is. In systems that provide write access to the MPLS-LSR-STD MIB, mplsIndexType SHOULD be used as a simple multi-digit integer encoded as an octet string. No further overloading of the meaning of an index SHOULD be made. In systems that do not offer write access to the MPLS-LSR-STD MIB, the mplsIndexType may contain implicit formatting that is specific to the implementation to convey additional information such as interface index, physical card or device, or application id. The interpretation of this additional formatting is implementation dependent and not covered in this document. Such formatting MUST NOT impact the basic functionality of read-only access to the MPLS-LSR-STD MIB by management applications that are not aware of the formatting rules. SIZE (1..24) · OCTET STRING

This contains the same value as the mplsOutSegmentIndex in the MPLS-LSR-STD-MIB's mplsOutSegmentTable.

MplsLdpLabelType1 = generic2 = atm3 = frameRelayThe Layer 2 label types which are defined for MPLS LDP and/or CR-LDP are generic(1), atm(2), or frameRelay(3). · Integer32

The Layer 2 Label Type.

MplsLspType1 = unknown2 = terminatingLsp3 = originatingLsp4 = crossConnectingLspTypes of Label Switch Paths (LSPs) on a Label Switching Router (LSR) or a Label Edge Router (LER) are: unknown(1) -- if the LSP is not known to be one of the following. terminatingLsp(2) -- if the LSP terminates on the LSR/LER, then this is an egressing LSP which ends on the LSR/LER, originatingLsp(3) -- if the LSP originates from this LSR/LER, then this is an ingressing LSP which is the head-end of the LSP, crossConnectingLsp(4) -- if the LSP ingresses and egresses on the LSR, then it is cross-connecting on that LSR. · Integer32

The type of LSP connection.

IndexIntegerAn integer which may be used as a table index. (1..4294967295) · Unsigned32 · hint d

The index which uniquely identifies this entry.

INTEGER1 = prefix2 = hostAddress · Integer32

Reference: RFC3036, Section 3.4.1. FEC TLV.

The type of the FEC. If the value of this object is 'prefix(1)' then the FEC type described by this row is an address prefix. If the value of this object is 'hostAddress(2)' then the FEC type described by this row is a host address.

InetAddressPrefixLengthDenotes the length of a generic Internet network address prefix. A value of n corresponds to an IP address mask that has n contiguous 1-bits from the most significant bit (MSB), with all other bits set to 0. An InetAddressPrefixLength value is always interpreted within the context of an InetAddressType value. Every usage of the InetAddressPrefixLength textual convention is required to specify the InetAddressType object that provides the context. It is suggested that the InetAddressType object be logically registered before the object(s) that use the InetAddressPrefixLength textual convention, if they appear in the same logical row. InetAddressPrefixLength values larger than the maximum length of an IP address for a specific InetAddressType are treated as the maximum significant value applicable for the InetAddressType. The maximum significant value is 32 for the InetAddressType 'ipv4(1)' and 'ipv4z(3)' and 128 for the InetAddressType 'ipv6(2)' and 'ipv6z(4)'. The maximum significant value for the InetAddressType 'dns(16)' is 0. The value zero is object-specific and must be defined as part of the description of any object that uses this syntax. Examples of the usage of zero might include situations where the Internet network address prefix is unknown or does not apply. The upper bound of the prefix length has been chosen to be consistent with the maximum size of an InetAddress. (0..2040) · Unsigned32 · hint d

Reference: RFC3036, Section 3.4.1. FEC TLV.

If the value of the 'mplsFecType' is 'hostAddress(2)' then this object is undefined. If the value of 'mplsFecType' is 'prefix(1)' then the value of this object is the length in bits of the address prefix represented by 'mplsFecAddr', or zero. If the value of this object is zero, this indicates that the prefix matches all addresses. In this case the address prefix MUST also be zero (i.e., 'mplsFecAddr' should have the value of zero.)

InetAddressType0 = unknown1 = ipv42 = ipv63 = ipv4z4 = ipv6z16 = dnsA value that represents a type of Internet address. unknown(0) An unknown address type. This value MUST be used if the value of the corresponding InetAddress object is a zero-length string. It may also be used to indicate an IP address that is not in one of the formats defined below. ipv4(1) An IPv4 address as defined by the InetAddressIPv4 textual convention. ipv6(2) An IPv6 address as defined by the InetAddressIPv6 textual convention. ipv4z(3) A non-global IPv4 address including a zone index as defined by the InetAddressIPv4z textual convention. ipv6z(4) A non-global IPv6 address including a zone index as defined by the InetAddressIPv6z textual convention. dns(16) A DNS domain name as defined by the InetAddressDNS textual convention. Each definition of a concrete InetAddressType value must be accompanied by a definition of a textual convention for use with that InetAddressType. To support future extensions, the InetAddressType textual convention SHOULD NOT be sub-typed in object type definitions. It MAY be sub-typed in compliance statements in order to require only a subset of these address types for a compliant implementation. Implementations must ensure that InetAddressType objects and any dependent objects (e.g., InetAddress objects) are consistent. An inconsistentValue error must be generated if an attempt to change an InetAddressType object would, for example, lead to an undefined InetAddress value. In particular, InetAddressType/InetAddress pairs must be changed together if the address type changes (e.g., from ipv6(2) to ipv4(1)). · Integer32

Reference: RFC3036, Section 3.4.1. FEC TLV.

The value of this object is the type of the Internet address. The value of this object, decides how the value of the mplsFecAddr object is interpreted.

InetAddressDenotes a generic Internet address. An InetAddress value is always interpreted within the context of an InetAddressType value. Every usage of the InetAddress textual convention is required to specify the InetAddressType object that provides the context. It is suggested that the InetAddressType object be logically registered before the object(s) that use the InetAddress textual convention, if they appear in the same logical row. The value of an InetAddress object must always be consistent with the value of the associated InetAddressType object. Attempts to set an InetAddress object to a value inconsistent with the associated InetAddressType must fail with an inconsistentValue error. When this textual convention is used as the syntax of an index object, there may be issues with the limit of 128 sub-identifiers specified in SMIv2, STD 58. In this case, the object definition MUST include a 'SIZE' clause to limit the number of potential instance sub-identifiers; otherwise the applicable constraints MUST be stated in the appropriate conceptual row DESCRIPTION clauses, or in the surrounding documentation if there is no single DESCRIPTION clause that is appropriate. SIZE (0..255) · OCTET STRING

Reference: RFC3036, Section 3.4.1 FEC TLV.

The value of this object is interpreted based on the value of the 'mplsFecAddrType' object. This address is then further interpretted as an being used with the address prefix, or as the host address. This further interpretation is indicated by the 'mplsFecType' object. In other words, the FEC element is populated according to the Prefix FEC Element value encoding, or the Host Address FEC Element encoding.

StorageType1 = other2 = volatile3 = nonVolatile4 = permanent5 = readOnlyDescribes the memory realization of a conceptual row. A row which is volatile(2) is lost upon reboot. A row which is either nonVolatile(3), permanent(4) or readOnly(5), is backed up by stable storage. A row which is permanent(4) can be changed but not deleted. A row which is readOnly(5) cannot be changed nor deleted. If the value of an object with this syntax is either permanent(4) or readOnly(5), it cannot be written. Conversely, if the value is either other(1), volatile(2) or nonVolatile(3), it cannot be modified to be permanent(4) or readOnly(5). (All illegal modifications result in a 'wrongValue' error.) Every usage of this textual convention is required to specify the columnar objects which a permanent(4) row must at a minimum allow to be writable. · Integer32

The storage type for this conceptual row. Conceptual rows having the value 'permanent(4)' need not allow write-access to any columnar objects in the row.

RowStatus1 = active2 = notInService3 = notReady4 = createAndGo5 = createAndWait6 = destroyThe RowStatus textual convention is used to manage the creation and deletion of conceptual rows, and is used as the value of the SYNTAX clause for the status column of a conceptual row (as described in Section 7.7.1 of [2].) The status column has six defined values: - `active', which indicates that the conceptual row is available for use by the managed device; - `notInService', which indicates that the conceptual row exists in the agent, but is unavailable for use by the managed device (see NOTE below); 'notInService' has no implication regarding the internal consistency of the row, availability of resources, or consistency with the current state of the managed device; - `notReady', which indicates that the conceptual row exists in the agent, but is missing information necessary in order to be available for use by the managed device (i.e., one or more required columns in the conceptual row have not been instanciated); - `createAndGo', which is supplied by a management station wishing to create a new instance of a conceptual row and to have its status automatically set to active, making it available for use by the managed device; - `createAndWait', which is supplied by a management station wishing to create a new instance of a conceptual row (but not make it available for use by the managed device); and, - `destroy', which is supplied by a management station wishing to delete all of the instances associated with an existing conceptual row. Whereas five of the six values (all except `notReady') may be specified in a management protocol set operation, only three values will be returned in response to a management protocol retrieval operation: `notReady', `notInService' or `active'. That is, when queried, an existing conceptual row has only three states: it is either available for use by the managed device (the status column has value `active'); it is not available for use by the managed device, though the agent has sufficient information to attempt to make it so (the status column has value `notInService'); or, it is not available for use by the managed device, and an attempt to make it so would fail because the agent has insufficient information (the state column has value `notReady'). NOTE WELL This textual convention may be used for a MIB table, irrespective of whether the values of that table's conceptual rows are able to be modified while it is active, or whether its conceptual rows must be taken out of service in order to be modified. That is, it is the responsibility of the DESCRIPTION clause of the status column to specify whether the status column must not be `active' in order for the value of some other column of the same conceptual row to be modified. If such a specification is made, affected columns may be changed by an SNMP set PDU if the RowStatus would not be equal to `active' either immediately before or after processing the PDU. In other words, if the PDU also contained a varbind that would change the RowStatus value, the column in question may be changed if the RowStatus was not equal to `active' as the PDU was received, or if the varbind sets the status to a value other than 'active'. Also note that whenever any elements of a row exist, the RowStatus column must also exist. To summarize the effect of having a conceptual row with a status column having a SYNTAX clause value of RowStatus, consider the following state diagram: STATE +--------------+-----------+-------------+------------- | A | B | C | D | |status col.|status column| |status column | is | is |status column ACTION |does not exist| notReady | notInService| is active --------------+--------------+-----------+-------------+------------- set status |noError ->D|inconsist- |inconsistent-|inconsistent- column to | or | entValue| Value| Value createAndGo |inconsistent- | | | | Value| | | --------------+--------------+-----------+-------------+------------- set status |noError see 1|inconsist- |inconsistent-|inconsistent- column to | or | entValue| Value| Value createAndWait |wrongValue | | | --------------+--------------+-----------+-------------+------------- set status |inconsistent- |inconsist- |noError |noError column to | Value| entValue| | active | | | | | | or | | | | | | | |see 2 ->D|see 8 ->D| ->D --------------+--------------+-----------+-------------+------------- set status |inconsistent- |inconsist- |noError |noError ->C column to | Value| entValue| | notInService | | | | | | or | | or | | | | | |see 3 ->C| ->C|see 6 --------------+--------------+-----------+-------------+------------- set status |noError |noError |noError |noError ->A column to | | | | or destroy | ->A| ->A| ->A|see 7 --------------+--------------+-----------+-------------+------------- set any other |see 4 |noError |noError |see 5 column to some| | | | value | | see 1| ->C| ->D --------------+--------------+-----------+-------------+------------- (1) goto B or C, depending on information available to the agent. (2) if other variable bindings included in the same PDU, provide values for all columns which are missing but required, and all columns have acceptable values, then return noError and goto D. (3) if other variable bindings included in the same PDU, provide legal values for all columns which are missing but required, then return noError and goto C. (4) at the discretion of the agent, the return value may be either: inconsistentName: because the agent does not choose to create such an instance when the corresponding RowStatus instance does not exist, or inconsistentValue: if the supplied value is inconsistent with the state of some other MIB object's value, or noError: because the agent chooses to create the instance. If noError is returned, then the instance of the status column must also be created, and the new state is B or C, depending on the information available to the agent. If inconsistentName or inconsistentValue is returned, the row remains in state A. (5) depending on the MIB definition for the column/table, either noError or inconsistentValue may be returned. (6) the return value can indicate one of the following errors: wrongValue: because the agent does not support notInService (e.g., an agent which does not support createAndWait), or inconsistentValue: because the agent is unable to take the row out of service at this time, perhaps because it is in use and cannot be de-activated. (7) the return value can indicate the following error: inconsistentValue: because the agent is unable to remove the row at this time, perhaps because it is in use and cannot be de-activated. (8) the transition to D can fail, e.g., if the values of the conceptual row are inconsistent, then the error code would be inconsistentValue. NOTE: Other processing of (this and other varbinds of) the set request may result in a response other than noError being returned, e.g., wrongValue, noCreation, etc. Conceptual Row Creation There are four potential interactions when creating a conceptual row: selecting an instance-identifier which is not in use; creating the conceptual row; initializing any objects for which the agent does not supply a default; and, making the conceptual row available for use by the managed device. Interaction 1: Selecting an Instance-Identifier The algorithm used to select an instance-identifier varies for each conceptual row. In some cases, the instance- identifier is semantically significant, e.g., the destination address of a route, and a management station selects the instance-identifier according to the semantics. In other cases, the instance-identifier is used solely to distinguish conceptual rows, and a management station without specific knowledge of the conceptual row might examine the instances present in order to determine an unused instance-identifier. (This approach may be used, but it is often highly sub-optimal; however, it is also a questionable practice for a naive management station to attempt conceptual row creation.) Alternately, the MIB module which defines the conceptual row might provide one or more objects which provide assistance in determining an unused instance-identifier. For example, if the conceptual row is indexed by an integer-value, then an object having an integer-valued SYNTAX clause might be defined for such a purpose, allowing a management station to issue a management protocol retrieval operation. In order to avoid unnecessary collisions between competing management stations, `adjacent' retrievals of this object should be different. Finally, the management station could select a pseudo-random number to use as the index. In the event that this index was already in use and an inconsistentValue was returned in response to the management protocol set operation, the management station should simply select a new pseudo-random number and retry the operation. A MIB designer should choose between the two latter algorithms based on the size of the table (and therefore the efficiency of each algorithm). For tables in which a large number of entries are expected, it is recommended that a MIB object be defined that returns an acceptable index for creation. For tables with small numbers of entries, it is recommended that the latter pseudo-random index mechanism be used. Interaction 2: Creating the Conceptual Row Once an unused instance-identifier has been selected, the management station determines if it wishes to create and activate the conceptual row in one transaction or in a negotiated set of interactions. Interaction 2a: Creating and Activating the Conceptual Row The management station must first determine the column requirements, i.e., it must determine those columns for which it must or must not provide values. Depending on the complexity of the table and the management station's knowledge of the agent's capabilities, this determination can be made locally by the management station. Alternately, the management station issues a management protocol get operation to examine all columns in the conceptual row that it wishes to create. In response, for each column, there are three possible outcomes: - a value is returned, indicating that some other management station has already created this conceptual row. We return to interaction 1. - the exception `noSuchInstance' is returned, indicating that the agent implements the object-type associated with this column, and that this column in at least one conceptual row would be accessible in the MIB view used by the retrieval were it to exist. For those columns to which the agent provides read-create access, the `noSuchInstance' exception tells the management station that it should supply a value for this column when the conceptual row is to be created. - the exception `noSuchObject' is returned, indicating that the agent does not implement the object-type associated with this column or that there is no conceptual row for which this column would be accessible in the MIB view used by the retrieval. As such, the management station can not issue any management protocol set operations to create an instance of this column. Once the column requirements have been determined, a management protocol set operation is accordingly issued. This operation also sets the new instance of the status column to `createAndGo'. When the agent processes the set operation, it verifies that it has sufficient information to make the conceptual row available for use by the managed device. The information available to the agent is provided by two sources: the management protocol set operation which creates the conceptual row, and, implementation-specific defaults supplied by the agent (note that an agent must provide implementation-specific defaults for at least those objects which it implements as read-only). If there is sufficient information available, then the conceptual row is created, a `noError' response is returned, the status column is set to `active', and no further interactions are necessary (i.e., interactions 3 and 4 are skipped). If there is insufficient information, then the conceptual row is not created, and the set operation fails with an error of `inconsistentValue'. On this error, the management station can issue a management protocol retrieval operation to determine if this was because it failed to specify a value for a required column, or, because the selected instance of the status column already existed. In the latter case, we return to interaction 1. In the former case, the management station can re-issue the set operation with the additional information, or begin interaction 2 again using `createAndWait' in order to negotiate creation of the conceptual row. NOTE WELL Regardless of the method used to determine the column requirements, it is possible that the management station might deem a column necessary when, in fact, the agent will not allow that particular columnar instance to be created or written. In this case, the management protocol set operation will fail with an error such as `noCreation' or `notWritable'. In this case, the management station decides whether it needs to be able to set a value for that particular columnar instance. If not, the management station re-issues the management protocol set operation, but without setting a value for that particular columnar instance; otherwise, the management station aborts the row creation algorithm. Interaction 2b: Negotiating the Creation of the Conceptual Row The management station issues a management protocol set operation which sets the desired instance of the status column to `createAndWait'. If the agent is unwilling to process a request of this sort, the set operation fails with an error of `wrongValue'. (As a consequence, such an agent must be prepared to accept a single management protocol set operation, i.e., interaction 2a above, containing all of the columns indicated by its column requirements.) Otherwise, the conceptual row is created, a `noError' response is returned, and the status column is immediately set to either `notInService' or `notReady', depending on whether it has sufficient information to (attempt to) make the conceptual row available for use by the managed device. If there is sufficient information available, then the status column is set to `notInService'; otherwise, if there is insufficient information, then the status column is set to `notReady'. Regardless, we proceed to interaction 3. Interaction 3: Initializing non-defaulted Objects The management station must now determine the column requirements. It issues a management protocol get operation to examine all columns in the created conceptual row. In the response, for each column, there are three possible outcomes: - a value is returned, indicating that the agent implements the object-type associated with this column and had sufficient information to provide a value. For those columns to which the agent provides read-create access (and for which the agent allows their values to be changed after their creation), a value return tells the management station that it may issue additional management protocol set operations, if it desires, in order to change the value associated with this column. - the exception `noSuchInstance' is returned, indicating that the agent implements the object-type associated with this column, and that this column in at least one conceptual row would be accessible in the MIB view used by the retrieval were it to exist. However, the agent does not have sufficient information to provide a value, and until a value is provided, the conceptual row may not be made available for use by the managed device. For those columns to which the agent provides read-create access, the `noSuchInstance' exception tells the management station that it must issue additional management protocol set operations, in order to provide a value associated with this column. - the exception `noSuchObject' is returned, indicating that the agent does not implement the object-type associated with this column or that there is no conceptual row for which this column would be accessible in the MIB view used by the retrieval. As such, the management station can not issue any management protocol set operations to create an instance of this column. If the value associated with the status column is `notReady', then the management station must first deal with all `noSuchInstance' columns, if any. Having done so, the value of the status column becomes `notInService', and we proceed to interaction 4. Interaction 4: Making the Conceptual Row Available Once the management station is satisfied with the values associated with the columns of the conceptual row, it issues a management protocol set operation to set the status column to `active'. If the agent has sufficient information to make the conceptual row available for use by the managed device, the management protocol set operation succeeds (a `noError' response is returned). Otherwise, the management protocol set operation fails with an error of `inconsistentValue'. NOTE WELL A conceptual row having a status column with value `notInService' or `notReady' is unavailable to the managed device. As such, it is possible for the managed device to create its own instances during the time between the management protocol set operation which sets the status column to `createAndWait' and the management protocol set operation which sets the status column to `active'. In this case, when the management protocol set operation is issued to set the status column to `active', the values held in the agent supersede those used by the managed device. If the management station is prevented from setting the status column to `active' (e.g., due to management station or network failure) the conceptual row will be left in the `notInService' or `notReady' state, consuming resources indefinitely. The agent must detect conceptual rows that have been in either state for an abnormally long period of time and remove them. It is the responsibility of the DESCRIPTION clause of the status column to indicate what an abnormally long period of time would be. This period of time should be long enough to allow for human response time (including `think time') between the creation of the conceptual row and the setting of the status to `active'. In the absence of such information in the DESCRIPTION clause, it is suggested that this period be approximately 5 minutes in length. This removal action applies not only to newly-created rows, but also to previously active rows which are set to, and left in, the notInService state for a prolonged period exceeding that which is considered normal for such a conceptual row. Conceptual Row Suspension When a conceptual row is `active', the management station may issue a management protocol set operation which sets the instance of the status column to `notInService'. If the agent is unwilling to do so, the set operation fails with an error of `wrongValue' or `inconsistentValue'. Otherwise, the conceptual row is taken out of service, and a `noError' response is returned. It is the responsibility of the DESCRIPTION clause of the status column to indicate under what circumstances the status column should be taken out of service (e.g., in order for the value of some other column of the same conceptual row to be modified). Conceptual Row Deletion For deletion of conceptual rows, a management protocol set operation is issued which sets the instance of the status column to `destroy'. This request may be made regardless of the current value of the status column (e.g., it is possible to delete conceptual rows which are either `notReady', `notInService' or `active'.) If the operation succeeds, then all instances associated with the conceptual row are immediately removed. · Integer32

The status of this conceptual row. If the value of this object is 'active(1)', then none of the writable objects of this entry can be modified, except to set this object to 'destroy(6)'. NOTE: if this row is being referenced by any entry in the mplsLdpLspFecTable, then a request to destroy this row, will result in an inconsistentValue error.

INTEGER1 = inSegment2 = outSegment · Integer32

If the value is inSegment(1), then this indicates that the following index, mplsLdpLspFecSegmentIndex, contains the same value as the mplsInSegmentLdpLspIndex. Otherwise, if the value of this object is outSegment(2), then this indicates that following index, mplsLdpLspFecSegmentIndex, contains the same value as the mplsOutSegmentLdpLspIndex.

MplsIndexTypeThis is an octet string that can be used as a table index in cases where a large addressable space is required such as on an LSR where many applications may be provisioning labels. Note that the string containing the single octet with the value 0x00 is a reserved value used to represent special cases. When this TEXTUAL-CONVENTION is used as the SYNTAX of an object, the DESCRIPTION clause MUST specify if this special value is valid and if so what the special meaning is. In systems that provide write access to the MPLS-LSR-STD MIB, mplsIndexType SHOULD be used as a simple multi-digit integer encoded as an octet string. No further overloading of the meaning of an index SHOULD be made. In systems that do not offer write access to the MPLS-LSR-STD MIB, the mplsIndexType may contain implicit formatting that is specific to the implementation to convey additional information such as interface index, physical card or device, or application id. The interpretation of this additional formatting is implementation dependent and not covered in this document. Such formatting MUST NOT impact the basic functionality of read-only access to the MPLS-LSR-STD MIB by management applications that are not aware of the formatting rules. SIZE (1..24) · OCTET STRING

This index is interpretted by using the value of the mplsLdpLspFecSegment. If the mplsLdpLspFecSegment is inSegment(1), then this index has the same value as mplsInSegmentLdpLspIndex. If the mplsLdpLspFecSegment is outSegment(2), then this index has the same value as mplsOutSegmentLdpLspIndex.

IndexIntegerAn integer which may be used as a table index. (1..4294967295) · Unsigned32 · hint d

This index identifies the FEC entry in the mplsFecTable associated with this session. In other words, the value of this index is the same as the value of the mplsFecIndex that denotes the FEC associated with this Session.

StorageType1 = other2 = volatile3 = nonVolatile4 = permanent5 = readOnlyDescribes the memory realization of a conceptual row. A row which is volatile(2) is lost upon reboot. A row which is either nonVolatile(3), permanent(4) or readOnly(5), is backed up by stable storage. A row which is permanent(4) can be changed but not deleted. A row which is readOnly(5) cannot be changed nor deleted. If the value of an object with this syntax is either permanent(4) or readOnly(5), it cannot be written. Conversely, if the value is either other(1), volatile(2) or nonVolatile(3), it cannot be modified to be permanent(4) or readOnly(5). (All illegal modifications result in a 'wrongValue' error.) Every usage of this textual convention is required to specify the columnar objects which a permanent(4) row must at a minimum allow to be writable. · Integer32

The storage type for this conceptual row. Conceptual rows having the value 'permanent(4)' need not allow write-access to any columnar objects in the row.

RowStatus1 = active2 = notInService3 = notReady4 = createAndGo5 = createAndWait6 = destroyThe RowStatus textual convention is used to manage the creation and deletion of conceptual rows, and is used as the value of the SYNTAX clause for the status column of a conceptual row (as described in Section 7.7.1 of [2].) The status column has six defined values: - `active', which indicates that the conceptual row is available for use by the managed device; - `notInService', which indicates that the conceptual row exists in the agent, but is unavailable for use by the managed device (see NOTE below); 'notInService' has no implication regarding the internal consistency of the row, availability of resources, or consistency with the current state of the managed device; - `notReady', which indicates that the conceptual row exists in the agent, but is missing information necessary in order to be available for use by the managed device (i.e., one or more required columns in the conceptual row have not been instanciated); - `createAndGo', which is supplied by a management station wishing to create a new instance of a conceptual row and to have its status automatically set to active, making it available for use by the managed device; - `createAndWait', which is supplied by a management station wishing to create a new instance of a conceptual row (but not make it available for use by the managed device); and, - `destroy', which is supplied by a management station wishing to delete all of the instances associated with an existing conceptual row. Whereas five of the six values (all except `notReady') may be specified in a management protocol set operation, only three values will be returned in response to a management protocol retrieval operation: `notReady', `notInService' or `active'. That is, when queried, an existing conceptual row has only three states: it is either available for use by the managed device (the status column has value `active'); it is not available for use by the managed device, though the agent has sufficient information to attempt to make it so (the status column has value `notInService'); or, it is not available for use by the managed device, and an attempt to make it so would fail because the agent has insufficient information (the state column has value `notReady'). NOTE WELL This textual convention may be used for a MIB table, irrespective of whether the values of that table's conceptual rows are able to be modified while it is active, or whether its conceptual rows must be taken out of service in order to be modified. That is, it is the responsibility of the DESCRIPTION clause of the status column to specify whether the status column must not be `active' in order for the value of some other column of the same conceptual row to be modified. If such a specification is made, affected columns may be changed by an SNMP set PDU if the RowStatus would not be equal to `active' either immediately before or after processing the PDU. In other words, if the PDU also contained a varbind that would change the RowStatus value, the column in question may be changed if the RowStatus was not equal to `active' as the PDU was received, or if the varbind sets the status to a value other than 'active'. Also note that whenever any elements of a row exist, the RowStatus column must also exist. To summarize the effect of having a conceptual row with a status column having a SYNTAX clause value of RowStatus, consider the following state diagram: STATE +--------------+-----------+-------------+------------- | A | B | C | D | |status col.|status column| |status column | is | is |status column ACTION |does not exist| notReady | notInService| is active --------------+--------------+-----------+-------------+------------- set status |noError ->D|inconsist- |inconsistent-|inconsistent- column to | or | entValue| Value| Value createAndGo |inconsistent- | | | | Value| | | --------------+--------------+-----------+-------------+------------- set status |noError see 1|inconsist- |inconsistent-|inconsistent- column to | or | entValue| Value| Value createAndWait |wrongValue | | | --------------+--------------+-----------+-------------+------------- set status |inconsistent- |inconsist- |noError |noError column to | Value| entValue| | active | | | | | | or | | | | | | | |see 2 ->D|see 8 ->D| ->D --------------+--------------+-----------+-------------+------------- set status |inconsistent- |inconsist- |noError |noError ->C column to | Value| entValue| | notInService | | | | | | or | | or | | | | | |see 3 ->C| ->C|see 6 --------------+--------------+-----------+-------------+------------- set status |noError |noError |noError |noError ->A column to | | | | or destroy | ->A| ->A| ->A|see 7 --------------+--------------+-----------+-------------+------------- set any other |see 4 |noError |noError |see 5 column to some| | | | value | | see 1| ->C| ->D --------------+--------------+-----------+-------------+------------- (1) goto B or C, depending on information available to the agent. (2) if other variable bindings included in the same PDU, provide values for all columns which are missing but required, and all columns have acceptable values, then return noError and goto D. (3) if other variable bindings included in the same PDU, provide legal values for all columns which are missing but required, then return noError and goto C. (4) at the discretion of the agent, the return value may be either: inconsistentName: because the agent does not choose to create such an instance when the corresponding RowStatus instance does not exist, or inconsistentValue: if the supplied value is inconsistent with the state of some other MIB object's value, or noError: because the agent chooses to create the instance. If noError is returned, then the instance of the status column must also be created, and the new state is B or C, depending on the information available to the agent. If inconsistentName or inconsistentValue is returned, the row remains in state A. (5) depending on the MIB definition for the column/table, either noError or inconsistentValue may be returned. (6) the return value can indicate one of the following errors: wrongValue: because the agent does not support notInService (e.g., an agent which does not support createAndWait), or inconsistentValue: because the agent is unable to take the row out of service at this time, perhaps because it is in use and cannot be de-activated. (7) the return value can indicate the following error: inconsistentValue: because the agent is unable to remove the row at this time, perhaps because it is in use and cannot be de-activated. (8) the transition to D can fail, e.g., if the values of the conceptual row are inconsistent, then the error code would be inconsistentValue. NOTE: Other processing of (this and other varbinds of) the set request may result in a response other than noError being returned, e.g., wrongValue, noCreation, etc. Conceptual Row Creation There are four potential interactions when creating a conceptual row: selecting an instance-identifier which is not in use; creating the conceptual row; initializing any objects for which the agent does not supply a default; and, making the conceptual row available for use by the managed device. Interaction 1: Selecting an Instance-Identifier The algorithm used to select an instance-identifier varies for each conceptual row. In some cases, the instance- identifier is semantically significant, e.g., the destination address of a route, and a management station selects the instance-identifier according to the semantics. In other cases, the instance-identifier is used solely to distinguish conceptual rows, and a management station without specific knowledge of the conceptual row might examine the instances present in order to determine an unused instance-identifier. (This approach may be used, but it is often highly sub-optimal; however, it is also a questionable practice for a naive management station to attempt conceptual row creation.) Alternately, the MIB module which defines the conceptual row might provide one or more objects which provide assistance in determining an unused instance-identifier. For example, if the conceptual row is indexed by an integer-value, then an object having an integer-valued SYNTAX clause might be defined for such a purpose, allowing a management station to issue a management protocol retrieval operation. In order to avoid unnecessary collisions between competing management stations, `adjacent' retrievals of this object should be different. Finally, the management station could select a pseudo-random number to use as the index. In the event that this index was already in use and an inconsistentValue was returned in response to the management protocol set operation, the management station should simply select a new pseudo-random number and retry the operation. A MIB designer should choose between the two latter algorithms based on the size of the table (and therefore the efficiency of each algorithm). For tables in which a large number of entries are expected, it is recommended that a MIB object be defined that returns an acceptable index for creation. For tables with small numbers of entries, it is recommended that the latter pseudo-random index mechanism be used. Interaction 2: Creating the Conceptual Row Once an unused instance-identifier has been selected, the management station determines if it wishes to create and activate the conceptual row in one transaction or in a negotiated set of interactions. Interaction 2a: Creating and Activating the Conceptual Row The management station must first determine the column requirements, i.e., it must determine those columns for which it must or must not provide values. Depending on the complexity of the table and the management station's knowledge of the agent's capabilities, this determination can be made locally by the management station. Alternately, the management station issues a management protocol get operation to examine all columns in the conceptual row that it wishes to create. In response, for each column, there are three possible outcomes: - a value is returned, indicating that some other management station has already created this conceptual row. We return to interaction 1. - the exception `noSuchInstance' is returned, indicating that the agent implements the object-type associated with this column, and that this column in at least one conceptual row would be accessible in the MIB view used by the retrieval were it to exist. For those columns to which the agent provides read-create access, the `noSuchInstance' exception tells the management station that it should supply a value for this column when the conceptual row is to be created. - the exception `noSuchObject' is returned, indicating that the agent does not implement the object-type associated with this column or that there is no conceptual row for which this column would be accessible in the MIB view used by the retrieval. As such, the management station can not issue any management protocol set operations to create an instance of this column. Once the column requirements have been determined, a management protocol set operation is accordingly issued. This operation also sets the new instance of the status column to `createAndGo'. When the agent processes the set operation, it verifies that it has sufficient information to make the conceptual row available for use by the managed device. The information available to the agent is provided by two sources: the management protocol set operation which creates the conceptual row, and, implementation-specific defaults supplied by the agent (note that an agent must provide implementation-specific defaults for at least those objects which it implements as read-only). If there is sufficient information available, then the conceptual row is created, a `noError' response is returned, the status column is set to `active', and no further interactions are necessary (i.e., interactions 3 and 4 are skipped). If there is insufficient information, then the conceptual row is not created, and the set operation fails with an error of `inconsistentValue'. On this error, the management station can issue a management protocol retrieval operation to determine if this was because it failed to specify a value for a required column, or, because the selected instance of the status column already existed. In the latter case, we return to interaction 1. In the former case, the management station can re-issue the set operation with the additional information, or begin interaction 2 again using `createAndWait' in order to negotiate creation of the conceptual row. NOTE WELL Regardless of the method used to determine the column requirements, it is possible that the management station might deem a column necessary when, in fact, the agent will not allow that particular columnar instance to be created or written. In this case, the management protocol set operation will fail with an error such as `noCreation' or `notWritable'. In this case, the management station decides whether it needs to be able to set a value for that particular columnar instance. If not, the management station re-issues the management protocol set operation, but without setting a value for that particular columnar instance; otherwise, the management station aborts the row creation algorithm. Interaction 2b: Negotiating the Creation of the Conceptual Row The management station issues a management protocol set operation which sets the desired instance of the status column to `createAndWait'. If the agent is unwilling to process a request of this sort, the set operation fails with an error of `wrongValue'. (As a consequence, such an agent must be prepared to accept a single management protocol set operation, i.e., interaction 2a above, containing all of the columns indicated by its column requirements.) Otherwise, the conceptual row is created, a `noError' response is returned, and the status column is immediately set to either `notInService' or `notReady', depending on whether it has sufficient information to (attempt to) make the conceptual row available for use by the managed device. If there is sufficient information available, then the status column is set to `notInService'; otherwise, if there is insufficient information, then the status column is set to `notReady'. Regardless, we proceed to interaction 3. Interaction 3: Initializing non-defaulted Objects The management station must now determine the column requirements. It issues a management protocol get operation to examine all columns in the created conceptual row. In the response, for each column, there are three possible outcomes: - a value is returned, indicating that the agent implements the object-type associated with this column and had sufficient information to provide a value. For those columns to which the agent provides read-create access (and for which the agent allows their values to be changed after their creation), a value return tells the management station that it may issue additional management protocol set operations, if it desires, in order to change the value associated with this column. - the exception `noSuchInstance' is returned, indicating that the agent implements the object-type associated with this column, and that this column in at least one conceptual row would be accessible in the MIB view used by the retrieval were it to exist. However, the agent does not have sufficient information to provide a value, and until a value is provided, the conceptual row may not be made available for use by the managed device. For those columns to which the agent provides read-create access, the `noSuchInstance' exception tells the management station that it must issue additional management protocol set operations, in order to provide a value associated with this column. - the exception `noSuchObject' is returned, indicating that the agent does not implement the object-type associated with this column or that there is no conceptual row for which this column would be accessible in the MIB view used by the retrieval. As such, the management station can not issue any management protocol set operations to create an instance of this column. If the value associated with the status column is `notReady', then the management station must first deal with all `noSuchInstance' columns, if any. Having done so, the value of the status column becomes `notInService', and we proceed to interaction 4. Interaction 4: Making the Conceptual Row Available Once the management station is satisfied with the values associated with the columns of the conceptual row, it issues a management protocol set operation to set the status column to `active'. If the agent has sufficient information to make the conceptual row available for use by the managed device, the management protocol set operation succeeds (a `noError' response is returned). Otherwise, the management protocol set operation fails with an error of `inconsistentValue'. NOTE WELL A conceptual row having a status column with value `notInService' or `notReady' is unavailable to the managed device. As such, it is possible for the managed device to create its own instances during the time between the management protocol set operation which sets the status column to `createAndWait' and the management protocol set operation which sets the status column to `active'. In this case, when the management protocol set operation is issued to set the status column to `active', the values held in the agent supersede those used by the managed device. If the management station is prevented from setting the status column to `active' (e.g., due to management station or network failure) the conceptual row will be left in the `notInService' or `notReady' state, consuming resources indefinitely. The agent must detect conceptual rows that have been in either state for an abnormally long period of time and remove them. It is the responsibility of the DESCRIPTION clause of the status column to indicate what an abnormally long period of time would be. This period of time should be long enough to allow for human response time (including `think time') between the creation of the conceptual row and the setting of the status to `active'. In the absence of such information in the DESCRIPTION clause, it is suggested that this period be approximately 5 minutes in length. This removal action applies not only to newly-created rows, but also to previously active rows which are set to, and left in, the notInService state for a prolonged period exceeding that which is considered normal for such a conceptual row. Conceptual Row Suspension When a conceptual row is `active', the management station may issue a management protocol set operation which sets the instance of the status column to `notInService'. If the agent is unwilling to do so, the set operation fails with an error of `wrongValue' or `inconsistentValue'. Otherwise, the conceptual row is taken out of service, and a `noError' response is returned. It is the responsibility of the DESCRIPTION clause of the status column to indicate under what circumstances the status column should be taken out of service (e.g., in order for the value of some other column of the same conceptual row to be modified). Conceptual Row Deletion For deletion of conceptual rows, a management protocol set operation is issued which sets the instance of the status column to `destroy'. This request may be made regardless of the current value of the status column (e.g., it is possible to delete conceptual rows which are either `notReady', `notInService' or `active'.) If the operation succeeds, then all instances associated with the conceptual row are immediately removed. · Integer32

The status of this conceptual row. If the value of this object is 'active(1)', then none of the writable objects of this entry can be modified. The Agent should delete this row when the session ceases to exist. If an operator wants to associate the session with a different FEC, the recommended procedure is (as described in detail in the section entitled, 'Changing Values After Session Establishment', and again described in the DESCRIPTION clause of the mplsLdpEntityAdminStatus object) is to set the mplsLdpEntityAdminStatus to down, thereby explicitly causing a session to be torn down. This will also cause this entry to be deleted. Then, set the mplsLdpEntityAdminStatus to enable which enables a new session to be initiated. Once the session is initiated, an entry may be added to this table to associate the new session with a FEC.

Unsigned32 (1..4294967295)

An index which uniquely identifies this entry within a given session.

InetAddressType0 = unknown1 = ipv42 = ipv63 = ipv4z4 = ipv6z16 = dnsA value that represents a type of Internet address. unknown(0) An unknown address type. This value MUST be used if the value of the corresponding InetAddress object is a zero-length string. It may also be used to indicate an IP address that is not in one of the formats defined below. ipv4(1) An IPv4 address as defined by the InetAddressIPv4 textual convention. ipv6(2) An IPv6 address as defined by the InetAddressIPv6 textual convention. ipv4z(3) A non-global IPv4 address including a zone index as defined by the InetAddressIPv4z textual convention. ipv6z(4) A non-global IPv6 address including a zone index as defined by the InetAddressIPv6z textual convention. dns(16) A DNS domain name as defined by the InetAddressDNS textual convention. Each definition of a concrete InetAddressType value must be accompanied by a definition of a textual convention for use with that InetAddressType. To support future extensions, the InetAddressType textual convention SHOULD NOT be sub-typed in object type definitions. It MAY be sub-typed in compliance statements in order to require only a subset of these address types for a compliant implementation. Implementations must ensure that InetAddressType objects and any dependent objects (e.g., InetAddress objects) are consistent. An inconsistentValue error must be generated if an attempt to change an InetAddressType object would, for example, lead to an undefined InetAddress value. In particular, InetAddressType/InetAddress pairs must be changed together if the address type changes (e.g., from ipv6(2) to ipv4(1)). · Integer32

The internetwork layer address type of this Next Hop Address as specified in the Label Address Message associated with this Session. The value of this object indicates how to interpret the value of mplsLdpSessionPeerNextHopAddr.

InetAddressDenotes a generic Internet address. An InetAddress value is always interpreted within the context of an InetAddressType value. Every usage of the InetAddress textual convention is required to specify the InetAddressType object that provides the context. It is suggested that the InetAddressType object be logically registered before the object(s) that use the InetAddress textual convention, if they appear in the same logical row. The value of an InetAddress object must always be consistent with the value of the associated InetAddressType object. Attempts to set an InetAddress object to a value inconsistent with the associated InetAddressType must fail with an inconsistentValue error. When this textual convention is used as the syntax of an index object, there may be issues with the limit of 128 sub-identifiers specified in SMIv2, STD 58. In this case, the object definition MUST include a 'SIZE' clause to limit the number of potential instance sub-identifiers; otherwise the applicable constraints MUST be stated in the appropriate conceptual row DESCRIPTION clauses, or in the surrounding documentation if there is no single DESCRIPTION clause that is appropriate. SIZE (0..255) · OCTET STRING

Reference: RFC3036, Section 2.7. LDP Identifiers and Next Hop Addresses

The next hop address. The type of this address is specified by the value of the mplsLdpSessionPeerNextHopAddrType.