CTC Union FRM220-100AS-1, User Manual

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CHAPTER 3
PROVISIONING VIA TEXT MENU
3.10.3 The Management Information Base
The management information base (MIB) includes a collection of managed objects. Managed
objects are defined as parameters that can be managed, such as specific information on device
configuring or on performance statistics values.
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.
3.10.4 MIB Structure
The MIB has an inverted tree-like structure (root over leaves), 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. 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).
Since the general collection of MIB's can also be organized in a similar structure, under the
supervision of the Internet Activities Board (IAB), any parameter included in a MIB that is
recognized by the IAB is uniquely defined.
To provide the flexibility necessary in a global structure, MIB's are classified in various classes
(branches), one of them being the experimental branch, another being the management (mgmt)
branch, and yet another the group of private (enterprise-specific) branches. Under the private
enterprise-specific branch of MIB's, each enterprise (manufacturer) can be assigned a number,
which is its enterprise number. The assigned number designates the top of an enterprise-specific
sub-tree of non-standard MIB's.
Enterprise-specific MIB's are published and distributed by their creators, who are responsible for
their contents. The MIB supported by
100AS-1 SNMP Agent follows RFC 1213 (MIB-2 standard).
3.10.5 SNMP Communities
To enable the delimitation of management domains, SNMP uses "communities". Each community
is identified by a name, which is an alphanumeric string of up to 255 characters defined by the
user. Any SNMP entity (this term includes both managed nodes and management stations) is