Facilities
6.4
SNMP Facility
SNMP Communication on UDP/IP
At a Glance The SNMP (Simple Network Management Protocol) standard defines network management solutions in terms of protocol and the exchange of supervised data.
The SNMP structure relies on the following essential elements: z
The Manager allows entire or partial network supervision, z z
One or more Agents . Each supervised device has a software module named
Agent used by the SNMP protocol.
A MIB (Management Information Base) is a data base or collection of objects.
The SNMP module agent is implemented on the TSX ETY modules. This allows a
Manager to access MIB-II standardized objects from the agent TSX ETY via the
SNMP protocol. The MIB-II allows management of TCP/IP communication layers.
On the TSX ETY 410•/PORT/510• module, it is possible to also access objects from the MIB Ethernet Transparent Factory, which provide specific information on Global
Data, I/O Scanning and Messaging utilities.
Branching view of the MIB Ethernet Transparent Factory: experimental private enterprises schneidergroup transparentFactoryEthernet switch port502Messaging ioScanning globalData web addressServer deviceProfile
The source file of the private MIB Ethernet Transparent Factory is available on the
TSX ETY 410•/PORT/510• module. It can be downloaded from an internet navigator by clicking on the "Download MIB file" link on the HTTP server index page (See
Ethernet Module Diagnostic Pages, p. 121 ). This file may be compiled by the main
SNMP Managers on the market.
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Facilities
The SNMP
Protocol
The SNMP protocol defines 5 types of message between the agent and the manager. These messages are encapsulated in the UDP datagrams.
Messages from the manager to an agent: z z
Get_Request
: message used to obtain the value of one or more variables.
Get_Next_Request
: obtains the value of the next variables.
z Set_Request
: sets the value of a variable.
Messages from an agent to the manager: z Get_Response
: allows the agent to re-send the value of the requested variable.
z Trap
: allows asynchronous event signaling by the agent.
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Description of the Utilities
Facilities
The SNMP manager transmits read or write requests (
Set_Request
,
Get_Request
,
Get_Next_Request
, etc.) for objects defined in the
MIB - II SNMP, and the SNMP agent of the TSX ETY module responds.
SNMP Manager
Get_Response
Trap
Set_Request
Get_Request
Get_Next_Request
SNMP Agent
TSX ETY PLC Station
The module's SNMP agent transmits events (Traps) to the Manager. The managed
Traps systems are as follows: z Coldstart Trap
: z z
For the TSX ETY 110 module, the event is transmitted following a module supply Reset.
For TSX ETY 410•/PORT/510• modules, the event is transmitted following a module supply Reset, or following a processor Reset, or following the z downloading of an application to the PLC.
Authentication Failure Trap
: event transmitted following an authentication problem. The Community Name field in the received message is different to the one configured on the module. This trap can be checked when configuring the TSX ETY module.
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