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IconMonitoring of network infrastructure

case study

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The control and monitoring of technological processes is more and more based on network technologies using IP protocol. It is possible to use this protocol not only in Ethernet networks but also in wireless networks (WiFi - Wireless Fiedlity) and while communicating with devices with serial interface (using PPTP - Point to Point Tunneling Protocol), via phone lines, GSM and GPRS. Most devices using this protocol have implemented complete "IP protocol stack" including the application protocol SNMP (Simple Network Management Protocol). This protocol is used already for a long time for the purpose of control and monitoring of network devices within corporate IT systems and gradually, with fast growing industrial Ethernet, it starts to assert also within network infrastructure of technological process control. There are more and more devices of various producers that use SNMP protocol even for transfer of process data such as temperature, pressure, ...

The overview of communication infrastructure connecting individual technological units together as well as superior corporate information system can be obtained based on the information provided by our SAEAUT SNMP OPC Server.

monitoring1en (17K)

Image 1: Application platform with SAEAUT SNMP OPC Server

With its usage it is possible to determine what communication problems are caused by malfunctions in software applications of particular technological units. Suppliers of technological software applications will not be able to make excuses that their application is working properly and does not cause flooding of communication channels, if the administrator is able to prove from current and historical trends that it is not truth. From acquired data it will be possible to determine when it is necessary to strenghten or modernize the communication infrastructure. A very useful can be to integrate the control and monitoring of network infrastructure into an existing system of supervisory process control - (SCADA - Supervisory Control And Data Acquisition). SNMP OPC Server represents the connection of two technologies - SNMP and OPC. OPC (nowadays interpreted as Open Process Control) is not only a communication, but also a functional standard that ensures the interoperability between devices and software of various producers. SNMP OPC server allows variables, acquired or configured via SNMP protocol, to be converted into a format demanded by software application that includes an OPC client. There are lot of such applications. It is contained not only in every known SCADA application, but also in some dynamic process simulation applications. As a part of the shipment of our server, you can find examples of OPC clients with their source code in C++, MS VB and MS VB.NET. The idea of connection of SNMP and OPC technologies is not new. Our SAEAUT SNMP OPC server has several advantages over solutions of other vendors. First of all, it implements not only the newest OPC standards such as OPC DA 3.0 and OPC AE 1.1, but also OPC XML DA that allows to communicate with it through web services and this way to use it within service oriented architectures (SOA). You can try this with using of XML DA client shipped by us together with its souce code or with the help of a web browser (such as MS Internet Explorer).

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Image 2: SAEAUT SNMP OPC Server configurator with in-built JScript editor

The shipment of SAEAUT SNMP OPC Server consists of two basic applications - a configurator, its main purpose is to configure data to be transfered and the "runtime" application, that ensures the transfer of preconfigured data. In contrast to other products of other vendors, besides data transfer it is possible to process the data with our product with the help of various filter and control algorithms and this way to reduce the amount of data transferred to the client application or eliminate time delays during the transfer from OPC server to OPC client application. This functionality is ensured by the configurator's MS Jscript editor and by interpreting of these scripts in the "runtime" application. The number of many controlled and monitored devices in a network can be very high and the amount of transfered variables huge. To create a configuration including such great amount of data could be very difficult without two utilities that are included in the configurator. It is "IP Scanner", that scans monitored devices into a configuration database, and "MIB Browser" that allows to find out which variables are available on a given device and then, or even in a single step, to store them into the OPC server's configuration database.

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Image 3: MIB Browser of SAEAUT SNMP OPC Servera

SAEAUT SNMP OPC Server allows to monitor also devices without an active SNMP agent and in a OPC variable to transfer the time delay to a ICMP ping from the server to such device. A very useful can be the function to log and display the activities of OPC server into log files.

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Image 4: Selecting "logged" events

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Image 5: Browsing log files

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Image 6: IP scanner

By using our trio of products SAEAUT SNMP OPC server, OpcDbGateway and OPC Adapter you can create a very complex system of control, monitoring, data storage in process databases, alarms, reports, visualisation, logging and data transfer between intranet domains and over Internet.

monitoring7en (24K)

Image 7: Complex solution of monitoring with our products.

Flex4Grid - Horizon 2020 project
28 Jul 2017
Extensions DLLs, configurations and examples of process databases for OpcDbGateway and SAEAUT SCADA are starting to be published as open source on GitHub in repository OpcDbGatewayEnhancements. We would like to welcome the contributors to this project. ...
29 Jun 2017
OpcDbGateway enables to process data collected from different external processes and to write data to them using different means of inter-process communication. This article describes possibilities and one concrete implementation of inter-process communication based on the piping of standard output of an external process to OpcDbGateway runtime process. Ready-made or custom console applications communicating over pipes or parameters of command line interface string can considerably enhance configurable and/or programmed functionality of integrated applications based on OpcDbGateway
27 Jun 2017
OpcDbGateway enables to enhance base configurable functionality using custom DLLs. Data exchange between core runtime application and the custom DLL can be provided over a C-style functional interface or over shared process variables of the process image memory. Advantages and problems of both methods are discussed in this article.