RFC 1316 (rfc1316) - Page 2 of 17
Definitions of Managed Objects for Character Stream Devices
Alternative Format: Original Text Document
RFC 1316 Character MIB April 1992
defined using the subset of Abstract Syntax Notation One (ASN.1) [7]
defined in the SMI. In particular, each object has a name, a syntax,
and an encoding. The name is an object identifier, an
administratively assigned name, which specifies an object type.
The object type together with an object instance serves to uniquely
identify a specific instantiation of the object. For human
convenience, we often use a textual string, termed the OBJECT
DESCRIPTOR, to also refer to the object type.
The syntax of an object type defines the abstract data structure
corresponding to that object type. The ASN.1 language is used for
this purpose. However, the SMI [3] purposely restricts the ASN.1
constructs which may be used. These restrictions are explicitly made
for simplicity.
The encoding of an object type is simply how that object type is
represented using the object type's syntax. Implicitly tied to the
notion of an object type's syntax and encoding is how the object type
is represented when being transmitted on the network.
The SMI specifies the use of the basic encoding rules of ASN.1 [8],
subject to the additional requirements imposed by the SNMP.
3.1. Format of Definitions
Section 5 contains the specification of all object types contained in
this MIB module. The object types are defined using the conventions
defined in the SMI, as amended by the extensions specified in [9,10].
4. Overview
The Character MIB applies to interface ports that carry a character
stream, whether physical or virtual, serial or parallel, synchronous
or asynchronous. The most common example of a character port is a
hardware terminal port with an RS-232 interface. Another common
hardware example is a parallel printer port, say with a Centronics
interface. The concept also includes virtual terminal ports, such as
a software connection point for a remote console.
The Character MIB is one of a set of MIBs designed for complementary
use. At this writing, the set comprises:
Character MIB
PPP MIB
RS-232-like MIB
Parallel-printer-like MIB
Character MIB Working Group