SNMPv2-TC DEFINITIONS ::= BEGIN

IMPORTS

    TimeTicks         FROM SNMPv2-SMI;

-- definition of textual conventions

TEXTUAL-CONVENTION MACRO ::=

BEGIN

    TYPE NOTATION ::=

                  DisplayPart

                  "STATUS" Status

                  "DESCRIPTION" Text

                  ReferPart

                  "SYNTAX" Syntax

    VALUE NOTATION ::=

                   value(VALUE Syntax)      -- adapted ASN.1

    DisplayPart ::=

                  "DISPLAY-HINT" Text

                | empty

    Status ::=

                  "current"

                | "deprecated"

                | "obsolete"

    ReferPart ::=

                  "REFERENCE" Text

                | empty

    -- a character string as defined in [2]

    Text ::= value(IA5String)

    Syntax ::=   -- Must be one of the following:

                       -- a base type (or its refinement), or

                       -- a BITS pseudo-type

                  type

                | "BITS" "{" NamedBits "}"

    NamedBits ::= NamedBit

                | NamedBits "," NamedBit

    NamedBit ::=  identifier "(" number ")" -- number is nonnegative

END

DisplayString ::= TEXTUAL-CONVENTION

    DISPLAY-HINT "255a"

    STATUS       current

    DESCRIPTION

            "Represents textual information taken from the NVT ASCII

            character set, as defined in pages 4, 10-11 of RFC 854.

            To summarize RFC 854, the NVT ASCII repertoire specifies:

              - the use of character codes 0-127 (decimal)

              - the graphics characters (32-126) are interpreted as

                US ASCII

              - NUL, LF, CR, BEL, BS, HT, VT and FF have the special

                meanings specified in RFC 854

              - the other 25 codes have no standard interpretation

              - the sequence 'CR LF' means newline

              - the sequence 'CR NUL' means carriage-return

              - an 'LF' not preceded by a 'CR' means moving to the

                same column on the next line.

              - the sequence 'CR x' for any x other than LF or NUL is

                illegal.  (Note that this also means that a string may

                end with either 'CR LF' or 'CR NUL', but not with CR.)

            Any object defined using this syntax may not exceed 255

            characters in length."

    SYNTAX       OCTET STRING (SIZE (0..255))

PhysAddress ::= TEXTUAL-CONVENTION

    DISPLAY-HINT "1x:"

    STATUS       current

    DESCRIPTION

            "Represents media- or physical-level addresses."

    SYNTAX       OCTET STRING

MacAddress ::= TEXTUAL-CONVENTION

    DISPLAY-HINT "1x:"

    STATUS       current

    DESCRIPTION

            "Represents an 802 MAC address represented in the

            `canonical' order defined by IEEE 802.1a, i.e., as if it

            were transmitted least significant bit first, even though

            802.5 (in contrast to other 802.x protocols) requires MAC

            addresses to be transmitted most significant bit first."

    SYNTAX       OCTET STRING (SIZE (6))

TruthValue ::= TEXTUAL-CONVENTION

    STATUS       current

    DESCRIPTION

            "Represents a boolean value."

    SYNTAX       INTEGER { true(1), false(2) }

TestAndIncr ::= TEXTUAL-CONVENTION

    STATUS       current

    DESCRIPTION

            "Represents integer-valued information used for atomic

            operations.  When the management protocol is used to specify

            that an object instance having this syntax is to be

            modified, the new value supplied via the management protocol

            must precisely match the value presently held by the

            instance.  If not, the management protocol set operation

            fails with an error of `inconsistentValue'.  Otherwise, if

            the current value is the maximum value of 2^31-1 (2147483647

            decimal), then the value held by the instance is wrapped to

            zero; otherwise, the value held by the instance is

            incremented by one.  (Note that regardless of whether the

            management protocol set operation succeeds, the variable-

            binding in the request and response PDUs are identical.)

            The value of the ACCESS clause for objects having this

            syntax is either `read-write' or `read-create'.  When an

            instance of a columnar object having this syntax is created,

            any value may be supplied via the management protocol.

            When the network management portion of the system is re-

            initialized, the value of every object instance having this

            syntax must either be incremented from its value prior to

            the re-initialization, or (if the value prior to the re-

            initialization is unknown) be set to a pseudo-randomly

            generated value."

    SYNTAX       INTEGER (0..2147483647)

AutonomousType ::= TEXTUAL-CONVENTION

    STATUS       current

    DESCRIPTION

            "Represents an independently extensible type identification

            value.  It may, for example, indicate a particular sub-tree

            with further MIB definitions, or define a particular type of

            protocol or hardware."

    SYNTAX       OBJECT IDENTIFIER

InstancePointer ::= TEXTUAL-CONVENTION

    STATUS       obsolete

    DESCRIPTION

            "A pointer to either a specific instance of a MIB object or

            a conceptual row of a MIB table in the managed device.  In

            the latter case, by convention, it is the name of the

            particular instance of the first accessible columnar object

            in the conceptual row.

            The two uses of this textual convention are replaced by

            VariablePointer and RowPointer, respectively."

    SYNTAX       OBJECT IDENTIFIER

VariablePointer ::= TEXTUAL-CONVENTION

    STATUS       current

    DESCRIPTION

            "A pointer to a specific object instance.  For example,

            sysContact.0 or ifInOctets.3."

    SYNTAX       OBJECT IDENTIFIER

RowPointer ::= TEXTUAL-CONVENTION

    STATUS       current

    DESCRIPTION

            "Represents a pointer to a conceptual row.  The value is the

            name of the instance of the first accessible columnar object

            in the conceptual row.

            For example, ifIndex.3 would point to the 3rd row in the

            ifTable (note that if ifIndex were not-accessible, then

            ifDescr.3 would be used instead)."

    SYNTAX       OBJECT IDENTIFIER

RowStatus ::= TEXTUAL-CONVENTION

    STATUS       current

    DESCRIPTION

            "The 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."

    SYNTAX       INTEGER {

                     -- the following two values are states:

                     -- these values may be read or written

                     active(1),

                     notInService(2),

                     -- the following value is a state:

                     -- this value may be read, but not written

                     notReady(3),

                     -- the following three values are

                     -- actions: these values may be written,

                     --   but are never read

                     createAndGo(4),

                     createAndWait(5),

                     destroy(6)

                 }

TimeStamp ::= TEXTUAL-CONVENTION

    STATUS       current

    DESCRIPTION

            "The 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."

    SYNTAX       TimeTicks

TimeInterval ::= TEXTUAL-CONVENTION

    STATUS       current

    DESCRIPTION

            "A period of time, measured in units of 0.01 seconds."

    SYNTAX       INTEGER (0..2147483647)

DateAndTime ::= TEXTUAL-CONVENTION

    DISPLAY-HINT "2d-1d-1d,1d:1d:1d.1d,1a1d:1d"

    STATUS       current

    DESCRIPTION

            "A date-time specification.

            field  octets  contents                  range

            -----  ------  --------                  -----

              1      1-2   year*                     0..65536

              2       3    month                     1..12

              3       4    day                       1..31

              4       5    hour                      0..23

              5       6    minutes                   0..59

              6       7    seconds                   0..60

                           (use 60 for leap-second)

              7       8    deci-seconds              0..9

              8       9    direction from UTC        '+' / '-'

              9      10    hours from UTC*           0..13

             10      11    minutes from UTC          0..59

            * Notes:

            - the value of year is in network-byte order

            - daylight saving time in New Zealand is +13

            For example, Tuesday May 26, 1992 at 1:30:15 PM EDT would be

            displayed as:

                             1992-5-26,13:30:15.0,-4:0

            Note that if only local time is known, then timezone

            information (fields 8-10) is not present."

    SYNTAX       OCTET STRING (SIZE (8 | 11))

StorageType ::= TEXTUAL-CONVENTION

    STATUS       current

    DESCRIPTION

            "Describes 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."

    SYNTAX       INTEGER {

                     other(1),       -- eh?

                     volatile(2),    -- e.g., in RAM

                     nonVolatile(3), -- e.g., in NVRAM

                     permanent(4),   -- e.g., partially in ROM

                     readOnly(5)     -- e.g., completely in ROM

                 }

TDomain ::= TEXTUAL-CONVENTION

    STATUS       current

    DESCRIPTION

          "Denotes a kind of transport service.

          Some possible values, such as snmpUDPDomain, are defined in

          the SNMPv2-TM MIB module.  Other possible values are defined

          in other MIB modules."

    REFERENCE    "The SNMPv2-TM MIB module is defined in RFC 1906."

    SYNTAX       OBJECT IDENTIFIER

TAddress ::= TEXTUAL-CONVENTION

    STATUS       current

    DESCRIPTION

          "Denotes a transport service address.

          A TAddress value is always interpreted within the context of a

          TDomain value.  Thus, each definition of a TDomain value must

          be accompanied by a definition of a textual convention for use

          with that TDomain.  Some possible textual conventions, such as

          SnmpUDPAddress for snmpUDPDomain, are defined in the SNMPv2-TM

          MIB module.  Other possible textual conventions are defined in

          other MIB modules."

    REFERENCE    "The SNMPv2-TM MIB module is defined in RFC 1906."

    SYNTAX       OCTET STRING (SIZE (1..255))

END