GeoDesy GD-P1000E1000 - Manual (Page 46)

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11.1.6 SNMP Technology
SNMP is part of the Internet network management architecture. This architecture is
based on the interaction of many entities, as described in the following section.
The Internet Management Model
As specified in Internet RFCs and other documents, a network management system
comprises:
Network elements -- Sometimes called managed devices, network elements are
hardware devices such as computers, routers, and terminal servers that are
connected to networks.
Agents -- Agents are software modules that reside in network elements. They collect
and store management information such as the number of error packets received by
a network element.
Managed object -- A managed object is a characteristic of something that can be
managed. For example, a list of currently active TCP circuits in a particular host
computer is a managed object. Managed objects differ from variables, which are
particular object instances. Using our example, an object instance is a single active
TCP circuit in a particular host computer. Managed objects can be scalar (defining a
single object instance) or tabular (defining multiple, related instances).
Management information base (MIB) -- A MIB is a collection of managed objects
residing in a virtual information store. Collections of related managed objects are
defined in specific MIB modules.
Syntax notation -- A syntax notation is a language used to describe a MIB's managed
objects in a machine-independent format. Consistent use of a syntax notation allows
different types of computers to share information. Internet management systems use
a subset of the International Organization for Standardization's (ISO's) Open System
Interconnection (OSI) Abstract Syntax Notation 1 (ASN.1) to define both the packets
exchanged by the management protocol and the objects that are to be managed.
Structure of Management Information (SMI) -- The SMI defines the rules for
describing management information. The SMI is defined using ASN.1.
Network management stations (NMSs) -- Sometimes called consoles, these devices
execute management applications that monitor and control network elements.
Physically, NMSs are usually engineering workstation-caliber computers with fast
CPUs, megapixel color displays, substantial memory, and abundant disk space. At
least one NMS must be present in each managed environment.
Parties -- Newly defined in SNMPv2, a party is a logical SNMPv2 entity that can
initiate or receive SNMPv2 communication. Each SNMPv2 party comprises a single,
unique party identity, a logical network location, a single authentication protocol, and
a single privacy protocol. SNMPv2 messages are communicated between two