RFC1155-SMI DEFINITIONS ::= BEGIN

EXPORTS -- EVERYTHING
internet, directory, mgmt,
experimental, private, enterprises,
OBJECT-TYPE, ObjectName, ObjectSyntax, SimpleSyntax,
ApplicationSyntax, NetworkAddress, IpAddress,
Counter, Gauge, TimeTicks, Opaque;

-- the path to the root

internet OBJECT IDENTIFIER ::= { iso org(3) dod(6) 1 }

directory OBJECT IDENTIFIER ::= { internet 1 }

mgmt OBJECT IDENTIFIER ::= { internet 2 }

experimental OBJECT IDENTIFIER ::= { internet 3 }

private OBJECT IDENTIFIER ::= { internet 4 }
enterprises OBJECT IDENTIFIER ::= { private 1 }

-- definition of object types

OBJECT-TYPE MACRO ::=
BEGIN
TYPE NOTATION ::= "SYNTAX" type (TYPE ObjectSyntax)
"ACCESS" Access
"STATUS" Status
VALUE NOTATION ::= value (VALUE ObjectName)

Access ::= "read-only"
| "read-write"
| "write-only"
| "not-accessible"
Status ::= "mandatory"
| "optional"
| "obsolete"
END

-- names of objects in the MIB

ObjectName ::=
OBJECT IDENTIFIER

-- syntax of objects in the MIB

ObjectSyntax ::=
CHOICE {
simple
SimpleSyntax,
-- note that simple SEQUENCEs are not directly
-- mentioned here to keep things simple (i.e.,
-- prevent mis-use). However, application-wide
-- types which are IMPLICITly encoded simple
-- SEQUENCEs may appear in the following CHOICE

application-wide
ApplicationSyntax
}

SimpleSyntax ::=
CHOICE {
number
INTEGER,
string
OCTET STRING,
object
OBJECT IDENTIFIER,
empty
NULL
}

ApplicationSyntax ::=
CHOICE {
address
NetworkAddress,
counter
Counter,
gauge
Gauge,
ticks
TimeTicks,
arbitrary
Opaque

-- other application-wide types, as they are
-- defined, will be added here
}

-- application-wide types

NetworkAddress ::=
CHOICE {
internet
IpAddress
}

IpAddress ::=
[APPLICATION 0] -- in network-byte order
IMPLICIT OCTET STRING (SIZE (4))

Counter ::=
[APPLICATION 1]
IMPLICIT INTEGER (0..4294967295)

Gauge ::=
[APPLICATION 2]
IMPLICIT INTEGER (0..4294967295)

TimeTicks ::=
[APPLICATION 3]
IMPLICIT INTEGER (0..4294967295)

Opaque ::=
[APPLICATION 4] -- arbitrary ASN.1 value,
IMPLICIT OCTET STRING -- "double-wrapped"

END