CTC Union ETU-01A, Installation And Operation Manual

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Chapter 6. SNMP Option
108
November 2001
The MIB includes the definitions of relevant managed objects (MIB
variables) for the specific node. Various MIB's can be defined for various
management purposes, types of equipment, etc. The management data itself
is a collection of integer, string and MIB address variables that contain all
the information necessary to manage the node.
A leaf object’s definition includes the range of instances (values) and the
"access" rights:
Read-only Instances of an object can be read, but cannot be set.
Read-write Instances of an object can be read or set.
Write-only Instances of an object can be set, but cannot be read.
Not accessible Instances of an object cannot be read, nor set.
6.2.4 MIB Structure
The MIB has an inverted tree-like structure (root over branches), with
each definition of a managed instance forming one leaf, located at the end of
a branch of that tree. Each "leaf" in the MIB is reached by a unique path,
therefore by numbering the branching points, starting with the top, each leaf
can be uniquely defined by a sequence of numbers. The formal description
of the managed objects and the MIB structure is provided in a special
standardized format, called Abstract Syntax Notation 1, or ASN.1
(pronounced A-S-N dot one).