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HDT-02_H.264 High Definition Digital Camera Transmitter
MANUAL V9.9 144
6.4 SNMP
Simple Network Management Protocol (SNMP) is an Internet-standard
protocol for managing devices on IP networks. SNMP exposes management
data in the form of variables on the managed systems, which describe the
system ’s configuration. These variables can then be queried (and sometimes
set) by managing applications.
SNMP is an application-layer protocol and it runs over UDP at the transport
level. SNMP is based on a manager / agent model as shown below:
Figure 6.15: SNMP management system
The SNMP agent used is MIB-II compliant. The SVP MIB (Management
Information Base) provides a standard representation of the SNMP
Agent’s
available information and where it is stored. The MIB is defined according to
the ASN.1.
6.4.1 SNMP commands
Operation Description Sender
Get Readout the current value
of specific objects in the
MIB. NMS
Get next Readout the current value
of the next object in the
MIB. NMS
Set Change a value of a specific
object in the MIB. NMS
Get response Responds to a get, get next
or set request. Agent
Trap A trap is a mechanism to
trigger the NMS that a
change in the device has
occurred.
After receiving the trap the
NMS still has to poll the
device to find out the details
of the change.
Agent
Table 6.1: SNMP commands
Network Management
Station
SNMP agent