rfc2578.txt

著名的RFC文档,其中有一些文档是已经翻译成中文的的.

-- built-in ASN.1 types

SimpleSyntax ::=
    CHOICE {
        -- INTEGERs with a more restrictive range
        -- may also be used
        integer-value               -- includes Integer32
            INTEGER (-2147483648..2147483647),

        -- OCTET STRINGs with a more restrictive size
        -- may also be used
        string-value
            OCTET STRING (SIZE (0..65535)),

        objectID-value
            OBJECT IDENTIFIER
    }

-- indistinguishable from INTEGER, but never needs more than
-- 32-bits for a two's complement representation
Integer32 ::=
        INTEGER (-2147483648..2147483647)


-- application-wide types

ApplicationSyntax ::=
    CHOICE {
        ipAddress-value
            IpAddress,

        counter-value
            Counter32,

        timeticks-value
            TimeTicks,

        arbitrary-value
            Opaque,

        big-counter-value
            Counter64,

        unsigned-integer-value  -- includes Gauge32
            Unsigned32
    }

-- in network-byte order


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RFC 2578                         SMIv2                        April 1999


-- (this is a tagged type for historical reasons)
IpAddress ::=
    [APPLICATION 0]
        IMPLICIT OCTET STRING (SIZE (4))

-- this wraps
Counter32 ::=
    [APPLICATION 1]
        IMPLICIT INTEGER (0..4294967295)

-- this doesn't wrap
Gauge32 ::=
    [APPLICATION 2]
        IMPLICIT INTEGER (0..4294967295)

-- an unsigned 32-bit quantity
-- indistinguishable from Gauge32
Unsigned32 ::=
    [APPLICATION 2]
        IMPLICIT INTEGER (0..4294967295)

-- hundredths of seconds since an epoch
TimeTicks ::=
    [APPLICATION 3]
        IMPLICIT INTEGER (0..4294967295)

-- for backward-compatibility only
Opaque ::=
    [APPLICATION 4]
        IMPLICIT OCTET STRING

-- for counters that wrap in less than one hour with only 32 bits
Counter64 ::=
    [APPLICATION 6]
        IMPLICIT INTEGER (0..18446744073709551615)


-- definition for objects

OBJECT-TYPE MACRO ::=
BEGIN
    TYPE NOTATION ::=
                  "SYNTAX" Syntax
                  UnitsPart
                  "MAX-ACCESS" Access
                  "STATUS" Status
                  "DESCRIPTION" Text
                  ReferPart


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                  IndexPart
                  DefValPart

    VALUE NOTATION ::=
                  value(VALUE ObjectName)

    Syntax ::=   -- Must be one of the following:
                       -- a base type (or its refinement),
                       -- a textual convention (or its refinement), or
                       -- a BITS pseudo-type
                   type
                | "BITS" "{" NamedBits "}"

    NamedBits ::= NamedBit
                | NamedBits "," NamedBit

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

    UnitsPart ::=
                  "UNITS" Text
                | empty

    Access ::=
                  "not-accessible"
                | "accessible-for-notify"
                | "read-only"
                | "read-write"
                | "read-create"

    Status ::=
                  "current"
                | "deprecated"
                | "obsolete"

    ReferPart ::=
                  "REFERENCE" Text
                | empty

    IndexPart ::=
                  "INDEX"    "{" IndexTypes "}"
                | "AUGMENTS" "{" Entry      "}"
                | empty
    IndexTypes ::=
                  IndexType
                | IndexTypes "," IndexType
    IndexType ::=
                  "IMPLIED" Index
                | Index


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    Index ::=
                    -- use the SYNTAX value of the
                    -- correspondent OBJECT-TYPE invocation
                  value(ObjectName)
    Entry ::=
                    -- use the INDEX value of the
                    -- correspondent OBJECT-TYPE invocation
                  value(ObjectName)

    DefValPart ::= "DEFVAL" "{" Defvalue "}"
                | empty

    Defvalue ::=  -- must be valid for the type specified in
                  -- SYNTAX clause of same OBJECT-TYPE macro
                  value(ObjectSyntax)
                | "{" BitsValue "}"

    BitsValue ::= BitNames
                | empty

    BitNames ::=  BitName
                | BitNames "," BitName

    BitName ::= identifier

    -- a character string as defined in section 3.1.1
    Text ::= value(IA5String)
END


-- definitions for notifications

NOTIFICATION-TYPE MACRO ::=
BEGIN
    TYPE NOTATION ::=
                  ObjectsPart
                  "STATUS" Status
                  "DESCRIPTION" Text
                  ReferPart

    VALUE NOTATION ::=
                  value(VALUE NotificationName)

    ObjectsPart ::=
                  "OBJECTS" "{" Objects "}"
                | empty
    Objects ::=
                  Object


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                | Objects "," Object
    Object ::=
                  value(ObjectName)

    Status ::=
                  "current"
                | "deprecated"
                | "obsolete"

    ReferPart ::=
                  "REFERENCE" Text
                | empty

    -- a character string as defined in section 3.1.1
    Text ::= value(IA5String)
END

-- definitions of administrative identifiers

zeroDotZero    OBJECT-IDENTITY
    STATUS     current
    DESCRIPTION
            "A value used for null identifiers."
    ::= { 0 0 }

END

3.  Information Modules

   An "information module" is an ASN.1 module defining information
   relating to network management.

   The SMI describes how to use an adapted subset of ASN.1 (1988) to
   define an information module.  Further, additional restrictions are
   placed on "standard" information modules.  It is strongly recommended
   that "enterprise-specific" information modules also adhere to these
   restrictions.

   Typically, there are three kinds of information modules:

(1)  MIB modules, which contain definitions of inter-related managed
     objects, make use of the OBJECT-TYPE and NOTIFICATION-TYPE macros;

(2)  compliance statements for MIB modules, which make use of the
     MODULE-COMPLIANCE and OBJECT-GROUP macros [2]; and,

(3)  capability statements for agent implementations which make use of
     the AGENT-CAPABILITIES macros [2].


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   This classification scheme does not imply a rigid taxonomy.  For
   example, a "standard" information module will normally include
   definitions of managed objects and a compliance statement.
   Similarly, an "enterprise-specific" information module might include
   definitions of managed objects and a capability statement.  Of
   course, a "standard" information module may not contain capability
   statements.

   The constructs of ASN.1 allowed in SMIv2 information modules include:
   the IMPORTS clause, value definitions for OBJECT IDENTIFIERs, type
   definitions for SEQUENCEs (with restrictions), ASN.1 type assignments
   of the restricted ASN.1 types allowed in SMIv2, and instances of
   ASN.1 macros defined in this document and its companion documents [2,
   3].  Additional ASN.1 macros must not be defined in SMIv2 information
   modules.  SMIv1 macros must not be used in SMIv2 information modules.

   The names of all standard information modules must be unique (but
   different versions of the same information module should have the
   same name).  Developers of enterprise information modules are
   encouraged to choose names for their information modules that will
   have a low probability of colliding with standard or other enterprise
   information modules. An information module may not use the ASN.1
   construct of placing an object identifier value between the module
   name and the "DEFINITIONS" keyword.  For the purposes of this
   specification, an ASN.1 module name begins with an upper-case letter
   and continues with zero or more letters, digits, or hyphens, except
   that a hyphen can not be the last character, nor can there be two
   consecutive hyphens.

   All information modules start with exactly one invocation of the
   MODULE-IDENTITY macro, which provides contact information as well as
   revision history to distinguish between versions of the same
   information module.  This invocation must appear immediately after
   any IMPORTs statements.

3.1.  Macro Invocation

   Within an information module, each macro invocation appears as:

        <descriptor> <macro> <clauses> ::= <value>

   where <descriptor> corresponds to an ASN.1 identifier, <macro> names
   the macro being invoked, and <clauses> and <value> depend on the
   definition of the macro.  (Note that this definition of a descriptor
   applies to all macros defined in this memo and in [2].)





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   For the purposes of this specification, an ASN.1 identifier consists
   of one or more letters or digits, and its initial character must be a
   lower-case letter.  Note that hyphens are not allowed by this
   specification (except for use by information modules converted from
   SMIv1 which did allow hyphens).

   For all descriptors appearing in an information module, the