Arbiter Systems 1088A, Operation Manual

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232 Options List
C.22.5 SNMP Support
This section reviews in some more detail SNMP on the Model 1088A/B. Simple Network Man-
agement Protocol (SNMP) was created to provide a standard for managing different networks and
the devices on the networks. As such, SNMP is designed to operate on the application layer using
different transport protocols (e.g. TCP/IP and UDP), making it independent of network hardware.
SNMP operates on this basis in the Model 1088A/B.
An SNMP managed network consists of three components: A managed device, an agent and a
network-management system (NMS). The 1088A/B is a managed device running an SNMP agent
that responds to queries from the network-management system.
SNMP Version Information
Currently, there are three versions of SNMP defined: SNMP v1, v2 and v3. The Model 1088A/B
supports these three versions. Here are some differences between versions.
SNMP v1. Basic Operations and Features
•
GetUsed by the NMS to retrieve the value of one or more object instances from and agent.
•
GetNextUsed by the NMS to retrieve the value of the next object instance in a table or a list
within an agent.
•
SetUsed by the NMS to set the values of the object instances within an agent.
•
TrapUsed by agents to asynchronously inform the NMS of a significant event.
SNMP v2. Additional Operations and Features
•
GetBulkUsed by the NMS to efficiently retrieve large blocks of data.
•
InformAllows one NMS to send trap information to another NMS and to then receive a
response.
SNMP v3. Security Enhancement
•
User-based Security Model (USM) for SNMP message security.
•
View-based Access Control Model (VACM) for access control.
• Dynamically configure the SNMP agents using SNMP SET commands.
Management Information Base (MIB) Table
Object names are stored in a (MIB) table that reside on a computer, and correspond to values
in a managed device (the 1088A/B). The agent in the Option 34 will respond to queries from the
management program to return values of these objects. Currently, management programs may only
read the status of the Model 1088A/B and not configure settings. See Section C.22.5 for a print
out of the current MIB table. To obtain a soft copy of the MIB table for the Model 1088A/B, you
may download it from the Arbiter Systems website at the following address: www.arbiter.com.
SNMP Service
Descriptions that follow are based on the web interface. The SNMP service (agent) runs on the
Option 34 when enabled in the configuration. Figure C.41 illustrates the SNMP Status screen,