Networking and Architecture Exam Study Guide

Manual Release 1 Networking and Architecture Exam Study Guide Version 7.0 Citect Pty Ltd 3 Fitzsimons Lane GORDON NSW 2072 PO Box 174 PYMBLE NSW 207...
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Manual Release 1

Networking and Architecture Exam Study Guide Version 7.0

Citect Pty Ltd 3 Fitzsimons Lane GORDON NSW 2072 PO Box 174 PYMBLE NSW 2073 AUSTRALIA Telephone: Fax:

61 2 9496 7300 61 2 9496 7399

DISCLAIMER Citect Pty Ltd makes no representations or warranties with respect to this manual and, to the maximum extent permitted by law, expressly limits its liability for breach of any warranty that may be implied to the replacement of this manual with another. Furthermore, Citect Pty Ltd reserves the right to revise this publication at any time without incurring an obligation to notify any person of the revision. Citect Pty Ltd ABN 88 001 158 854 (“Citect”) Networking and Architecture Exam Study Guide Training Manual INTRODUCTION AND LEGAL NOTICE Your purchase of this official Networking and Architecture Exam Study Guide Training Manual entitles you to undertake the Networking and Architecture Exam Study Guide training course. The number allocated to you on purchase of this manual is your key to complete the course evaluation. Satisfactory completion of this evaluation is mandatory for you to obtain a Citect certificate of completion of the training course. The contents of this manual are proprietary to Citect Pty Ltd and all rights, including copyright, are reserved by Citect Pty Ltd. You must not copy any part of the manual in hard or electronic form or make any adaptation or other commercial use of it without Citect's prior written consent. Citect Pty Ltd will not accept any liability for action taken in reliance on this training manual.

COPYRIGHT © Copyright Citect Pty Ltd All rights reserved.

TRADEMARKS Citect Pty Ltd has made every effort to supply trademark information about company names, products and services mentioned in this manual. Trademarks shown below were derived from various sources. CitectSCADA, CitectHMI, CitectFacilities, CitectSCADA Reports and Ampla are registered trademarks of Citect Pty Ltd Windows, Windows NT, Windows 2000, Windows XP, MSSQL Server and Excel are trademarks of Microsoft Corporation. Oracle is a registered trademark of Oracle Corporation and/or its affiliates. Novell and NetWare are registered trademarks of Novell Inc. dBASE is a trademark of Borland Inc. General Notice: Some product names used in this manual are used for identification purposes only and may be trademarks of their respective companies. About Us Members of Citect’s team of Instructional Designers have tertiary qualifications in Education, Educational Course Development and are also experienced trainers in their own right; some are also published authors. Currently, the team is supporting a range of over 70 courses in multiple languages and multiple software environments. Authors Alynda Brown, David Heath

July 2008 Edition for Version 7.0 Manual Release 1 Written, Printed and bound in Australia

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Contents CHAPTER 1:

INTRODUCTION TO THE EXAMINATION SYSTEM .................................. 1-1

Overview .................................................................................................................... 1-1 Examination and Certification.................................................................................... 1-1 Registration................................................................................................................. 1-2 The Examination System............................................................................................ 1-4 Examination Instructions Course................................................................................ 1-7 Exam Questions.......................................................................................................... 1-8 The Examination ...................................................................................................... 1-10 Exam Sections .......................................................................................................... 1-14 Working through the Exam ...................................................................................... 1-17 Submitting an Exam ................................................................................................. 1-18 Completing the Exam ............................................................................................... 1-20 Successful Completion ............................................................................................. 1-21 CHAPTER 2:

NETWORKING AND ARCHITECTURE EXAM TOPICS ............................. 2-1

Overview .................................................................................................................... 2-1 Networking ................................................................................................................. 2-2 Citect Networking ...................................................................................................... 2-7 Redundancy ................................................................................................................ 2-9 Internet Display Client ............................................................................................. 2-10 Web Client................................................................................................................ 2-11 Object IDs................................................................................................................. 2-12 CHAPTER 3:

NAVIGATING THE KNOWLEDGE BASE .................................................. 3-1

Overview .................................................................................................................... 3-1 Searching .................................................................................................................... 3-2 APPENDIX A:

FIRST APPENDIX ................................................................................... A-1

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Chapter 1:

Introduction to the Examination System

Overview Introduction

There are not many people who enjoy taking exams. In fact most people view impending exams with some degree of trepidation. There are, however, three things that help alleviate anxiety – preparation, preparation and preparation. This Study Guide is designed to help prepare you for the exams in the Citect Certified SCADA Engineer stream. In this study guide you will see a list of suggested exercises, and a list of references for suggested reading.

The CCSE exams cover a very broad range of topics, so to enhance your chances of passing the exams it is advisable to take enough time to study the topics with which you are not yet familiar. The best resource is the Citect Educational Services Training courseware. Each of the exams is designed around the content in the Citect curriculum. Of course you also need to be familiar with searching the CitectSCADA Help files and searching the CitectSCADA Knowledge base.

This Chapter Covers These Topics: Examination and Certification ...............................................1-1 Registration............................................................................1-2 The Examination System .......................................................1-4 Examination Instructions Course...........................................1-7 Exam Questions .....................................................................1-8 The Examination..................................................................1-10 Exam Sections......................................................................1-14 Working through the Exam..................................................1-17 Submitting an Exam.............................................................1-18 Completing the Exam ..........................................................1-20 Successful Completion ........................................................1-21

Examination and Certification Citect Authorised Examination Centres

Citect has authorised selected offices throughout the world as Citect Authorised Examination Centres. These centres are most likely to be your local Citect Office or Partner. A list of Examination Centres is located on the Citect website. Any Authorised Examination Centre must have been approved by Citect Educational Services. We are currently in the process of authorising our Citect offices so many of the Citect offices are in provisional status. If you do not find your local office listed on this page contact them directly as they may be a Provisional Examination Centre. All examinations must be held under the supervision of an approved Citect Examination Supervisor.

Registration Registering for an Exam

Before anyone may sit for any of the Exams in the Citect Certified Engineer program they must register. This may be done in two ways: Contact a local Citect office or Register via the website To register for an exam through the website this page on the Citect website needs to be filled out with the candidate's details. When the request is submitted an email will be sent to the Exam Coordinator in the Examination Centre that has been specified. The Exam Coordinator will contact the candidate regarding the details of the examination. http://www3.citect.com/exams/register

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Registration (cont.) Why Register?

The registration process not only allows your local office to coordinate exams but is the first step in the exam process. When you register for the first time the Exam Coordinator in your region will arrange for your unique Student Login and Student Password. The Student Login and Password that you receive will be used in all of your Citect Exams. We will need an email address so that your exam results may be sent to you. The Student Login follows this format exam_firstname_lastname The Student Password is a computer generated random selection of characters. The password will generally not be revealed to you, instead the examination supervisor will log in on your behalf.

Exam Enrolment

The exam enrolment is created prior to the day of the exam. When the Exam coordinator registers the candidate to sit for a particular exam their Username is entered into the Enrolled User Group for that exam. The enrolment is disabled until the day of the exam.

The Day of the Exam

The Exams are supervised by Examination Supervisors. The exam may be held at the end of a training course or independently of any courses. When the candidate arrives at the Examination Centre they will need to identify themselves to the Exam Supervisor. If this is the candidate's first exam the Exam Supervisor will need to supply them with their Exam Username and Password. They will then be escorted to the Examination Room. The location of the testing room is most likely to be a Citect Training Room.

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The Examination System Open Book Exams

All exams are open book. The computers in the Examination room are loaded with an appropriate version of CitectSCADA for the exam being undertaken, the Knowledge Base and all PDF documents available on the distribution CD-ROM or DVD-ROM. However, no other material will be permitted in the Examination Room, for example, the Citect Educational Services Training Manuals or the Study Guides. The exams are supervised by the Exam Supervisor. Whilst candidates are allowed to refer to the online documentation and to create test projects on the installed CitectSCADA system, no speaking is allowed and no looking at another computer. The examination procedure does not allow: Notes to be taken in or out of the examination room Screen shots or copies of examination questions to be taken from the examination room USB keys or any other removable media to be taken in or out of the examination room Photographs of any type Talking Collaboration with anyone

Web Based Exams

All Citect Certified Exams are web based. Before you start your exam, the Exam Coordinator will have Internet Explorer loaded at the Citect Exam web page. For CitectSCADA V6.x exams, the Exam PC will be required to have the Adobe Flash player installed. This is not necessary for v7 exams as all Flash animations have been removed from the new exams.

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The Examination System (cont.) Logging In to the Exam System

The Examination system is hosted on the Citect UniverCITe website and can be accessed from a web browser as follows: External to the Citect WAN: learning.citect.com Within the Citect WAN: a URL shortcut will gain access: learning

exam_firstname_lastname password

GO

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Logging In to the Exam System (cont.)

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Examination Instructions Course Course for New Candidates

A course has been provided to introduce new candidates to the examination system. If this is a new candidate they should complete this course before proceeding.

!

Examination Examination Instructions

Instructions

Start -->

Next -->

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Exam Questions Single Answer

Read the question and select your response from the list of options. Select the radio button beside your choice.

True or False Response

These questions offer a simple choice between two responses. Occasionally, they will also be expressed as a choice between two specific possibilities.

Multiple Answers

These questions are expecting at least one response, possibly as many as four. Tick boxes are provided for you to select as many or as few responses as you think appropriate. In order to score the marks for these questions, you much select exactly the correct set of responses; there are no partial marks for partially correct responses.

Typed Responses

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A small number of questions expect a typed response.

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Exam Questions (cont.) Drag and Drop

These questions only exist in the v6.x exams. the candidate is expected to drag the buttons in the left column onto the responses on the right column. Click the submit button when done.

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The Examination Starting the Examination

Once a candidate has completed the Examination Instructions course they are ready to begin their first examination.

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Title Page

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The Examination (cont.)

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The Examination (cont.) Examination Instructions #

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The Flash Player is no longer needed for the examinations.

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Starting the Examination (cont.)

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Exam Sections Topics

Each Exam Section covers a specific Topic. These topics are listed when the exam is entered but before the exam starts.

Value

Each section contains a pool of questions. The candidate is given a random selection from this pool. Not all questions are of the same difficulty. Therefore different sections have different values assigned to the questions. However, all questions in each section have the same value. The Section information at the beginning of each section indicates the value of the questions.

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Exam Sections (cont.) Entering the Section

The Section Information page has a Start button that must be clicked to enter the section. The candidate should NOT press the Next --> link as this will not enter the section. Instead it will take them to the beginning of the following section.

Section Time

All Sections allow a certain maximum amount of time in which to complete your work. Each section of the examination corresponds to chapters in the courses and is timed independently. The available time is fixed for each exam and is also subdivided into allotments for each section of the exam. The system will not "bank" time - at the end of a section, any spare time is lost. The Introduction page of each section provides the candidate with the time available for that section.

The candidate is able to control when they start each section. The section timer starts when the candidate clicks the Start button This time is indicated by an onscreen counter/clock in the top right hand corner of the screen.

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Exam Sections (cont.) Completing a Section

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When the candidate clicks Submit, the section is graded and the section results are displayed. This is the reason why it is not possible to return to a section.

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Working through the Exam Exam Sections

Having confirmed your details, you are then presented with the exam sections you will encounter. Each of these sections is separately timed and questions in each section, although having equal value, may have different value to questions in other sections. Typically, there are easy questions worth few marks and hard questions worth more marks. This is your last opportunity to decide you're attempting the wrong exam!

Once you click the Start button (not shown in the graphic) timing commences for the first section. Inside a section

You will be given the name of the section and advised the value of each section and the total number of marks available in the section. The timer in the top-right corner of the screen commences a count-down. Click submit at the bottom of the screen to complete the section. You will be warned if there are un-completed questions and the section will not close.

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Submitting an Exam Last Exam Section

Once the examination has been completed the candidate needs to submit their examination. This is done by clicking the Click to Complete Course & upload Marks link.

Confirmation and Results

The examination completion is confirmed and the candidate may view their results by clicking the Grades link on the left side menu.

The page will display their overall result. The full section detail may be viewed by clicking the module name.

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Submitting an Exam (cont.) Detailed Results

The full section detail allows the candidate to view the results for each section so that they can see which sections they may need to review.

Passing Grade

The pass mark for all exams is 75%. Once all of the examshave been passed (or the upgrade exam for an existing CCSE), the CCSE Administrator will be advised automatically. The certificate will be mailed within a few days.

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Completing the Exam Uploading Your Marks

After submitting the final exam section, a screen will be presented inviting you to upload your marks.

Once done, you are advised that your final grade may be seen via the Grades link on the left-side menu. The exam is completed.

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Successful Completion Certificates

If the candidate has been successful in all the required examinations they will be given CCSE status. Unlike the course certificates a CCSE qualification is one that implies attainment of a level of expertise. In order to separate the two types of certificate given by Citect any accreditation that implies the attainment of expertise is represented by the word PASSED on the certificate. The certificates may be sent either directly to the candidate or to the examination centre.

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Chapter 2:

Networking and Architecture Exam Topics

Overview Introduction

You can configure a CitectHMI/SCADA monitoring and control system to suit any industrial application. CitectHMI/SCADA has been designed with flexibility in mind, so you can design a system to suit your exact requirements. CitectHMI/SCADA suits both small and large applications. Since CitectSCADA has a flexible architecture it will keep pace with your plant and information requirements as they change and expand. Whilst reliability is a key feature of computer hardware breakdowns do occur. It is for this reason that Redundancy is designed into CitectSCADA and can be implemented without changing the project configuration.

This Chapter Covers These Topics: Networking ............................................................................2-2 Citect Networking..................................................................2-7 Redundancy ...........................................................................2-9 Internet Display Client.........................................................2-10 Web Client ...........................................................................2-11 Object IDs ............................................................................2-12

Networking Servers and Clients

So what is a Server? What is a Client? Most people think of a Server as a repository for all of the company’s important files. However, that is only one type of Server. To put it simply: A Server is a computer that is able to share a resource. A Client is a computer that is connected to a resource. Any resource. It does not matter what operating system is installed. The Operating System is dictated by the type of Server the computer is going to be. If the computer is going to be a Domain Controller then you will need a specific operating system. If the computer is a workstation that is going to be able to share a printer then Windows 95 will do the job.

The screen shot above shows that this computer is both a Server and a Client. It is a Server because File and Printer Sharing for Microsoft Networks is installed and enabled. It is a Client because Client for Microsoft Networks is installed and enabled.

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Networking (cont.) Protocols

Protocols are the language of computers. If computers want to talk to one another, they must speak the same language, or in other words, use the same protocol. If they don’t use the same protocol, they cannot exchange information. The good thing about Windows 2000 is that it supports many of the common network protocols in use today, which makes it a good choice of operating system to use in different types of networks. Protocols are sets of rules that define how computers and components interact with one another. They are developed either by a single entity or by an organization made up of a group of entities. The International Organization for Standardization (ISO), located in Geneva, Switzerland, is responsible for developing and publishing standards. This group designed a standard that is used as a model for network communication, the Open Systems Interconnection (OSI) reference model.

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OSI Model

Network communication is a complex process, requiring that participating parties all be “on the same page.” Having a set of rules to follow increases the chance that information will be exchanged, which is why the OSI reference model was designed. The model is a guide for developers to follow when creating or implementing a protocol. The OSI model is divided into seven layers. Each layer defines a part of the network communication process, by specifying the layer’s function in transmitting data on the network. Network communication is information passed between the layers. Each layer is directly related to the layer above it and the layer below it. The following are the OSI reference model layers:

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Layer

Description

Physical

Responsible for putting the data on the medium.

Data Link

Defines how the data is accessed from the medium and how it is put on the medium.

Network

Makes sure the information has the address of where it needs to go.

Transport

Provides error-checking and makes sure the information arrives.

Session

Establishes communication channels between hosts.

Presentation

Formats the information.

Application

Defines the way applications interact with the network.

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Networking (cont.) TCP/IP

TCP/IP is really a suite of protocols. In other words, it consists of a number of protocols that together effect network communication. It is the most open of all the protocol stacks, and for this reason, it is the most utilized. Open in this sense means that no single vendor controls it, unlike IPX/SPX or AppleTalk, which are owned by Novell and Apple, respectively. Almost every operating system supports TCP/IP.

IP Address

In order to recognise different nodes on a network TCP/IP uses IP addresses. The IP address of your computer may be set at the level of your computer or it may be given an IP address dynamically using Dynamic Host Configuration Protocol (DHCP). The easiest way to check the IP address of your computer is to open a command window and type ipconfig at the command prompt.

An IP Address is made up of four sets of three numbers. Actually they are four sets of eight bits (Binary Digits). 11000000.10101000.00000000.11010100

When those bits are translated into decimal they become the numbers from zero to 255. 192.168. 0.212

An IP Address tells you two things – The Identity of the Network The Identity of the Host (Computer, Printer, I/O Device etc)

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Networking (cont.) NetBIOS Names

On a NetBIOS network, every computer must have a unique name. The computer is identified on the network at the Physical layer by a MAC (Media Access Control) address. This is simply as string of unique numbers embedded into the network card. Unfortunately this system is a little difficult for us poor humans to remember so we use systems to resolve names that are more meaningful to us into those MAC addresses and therefore makes them easier to remember. The Netbios name of your computer can be viewed and changed in the network properties. The computer name must be 15 or fewer characters long. A NetBIOS name can include alphanumeric characters but must not include any of the following special characters: !@#$%^&()-_’{}.~

Suggested Exercises

Use these suggested exercises to increase your understanding of the topic. Set up a network between two computers using TCP/IP as the protocol. Use IPConfig to check the IP Addresses and the Subnet Masks. Create shares on each computer. Ping each of the computers. Connect to the shares by typing the UNC names into the Address in Windows Explorer.

Further Reading

Use the following references to assist your understanding of the topic. CitectSCADA Help Topic - [LAN] parameters. CitectSCADA Help Topic - Configuring CitectSCADA to communicate over a WAN. Citect Knowledge Base Article Q2449: TCP/IP Port Settings. Citect Knowledge Base Article Q3070: Using TCP/IP Sockets with Citect. Citect Knowledge Base Article Q3984: NetBIOS and TCP/IP Advantages and Disadvantages.

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Citect Networking How CitectSCADA is Structured, Client/Server

Each CitectSCADA computer can be viewed as a client and potential server of CitectSCADA information (Reports/Alarms/Trends). On top of this, each CitectSCADA computer is fully capable of serving real-time I/O to clients, plus executing events and maintaining system time (Time Server).

Suggested Exercises

Use these suggested exercises to increase your understanding of the topic. Set up a project that is networked across several computers. Configure an I/O Server Configure a Citect cluster with different computers taking the I/O, Trend, Alarm and Report Server roles. Configure a Global Client to connect to two separate Citect clusters. Create a new tag and extension to a graphics page. Test that the on-line changes system will correctly propagate the update.

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Citect Networking (cont.) Further Reading

Use the following references to assist your understanding of the topic. CitectSCADA Help Topic - Setting up a Network. CitectSCADA Help Topic - Using TCP/IP for network communications. CitectSCADA Help Topic - Using Distributed Processing. CitectSCADA Help Topic - Using Distributed Servers. CitectSCADA Help Topic - [LAN] parameters. CitectSCADA Help Topic - Clustering. CitectSCADA Help Topic - Rules of Clustering. Citect Knowledge Base Article Q1378: Using Citect with Redundant LANs. Citect Knowledge Base Article Q3943: Implications for Citect and Microsoft Windows XP Service Pack 2.

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Redundancy Why Use Redundancy?

Many industrial plants cannot afford to have their CitectSCADA monitoring system fail at any time. Building redundancy into your system can prevent the loss of control and monitoring of your CitectSCADA system.

Suggested Exercises

Use these suggested exercises to increase your understanding of the topic. Create a project with a Primary and Standby I/O Server. Configure the Servers to also act as redundant Trend, Report and Alarm Servers. Add File Server Redundancy to the system. Configure a redundant Disk I/O Device. Disable the Primary Server and change some of the values on the Standby. Reconnect the Primary and watch what happens.

Further Reading

Use the following references to assist your understanding of the topic. CitectSCADA Help Topic - Building Redundancy into Your System. CitectSCADA Help Topic - Data Path Redundancy CitectSCADA Help Topic - Multiple Device Redundancy (Standby Data Paths) Citect Knowledge Base Article Q2228: Configuring a Redundant Disk PLC. Citect Knowledge Base Article Q3723: Trend Redundancy Backfilling.

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Internet Display Client Runtime Only CitectSCADA

If you have a computer with Internet access, you can use it to run your project over the Internet from a remote location. Your computer would then be called an Internet Display Client. This is basically a runtime-only version of CitectSCADA; you can run your project from that computer, just as you would from any normal Display Client. However, an Internet Display Client cannot be a server, and it cannot be used to make configuration changes - you can only run the project as it is on the server.

Suggested Exercises

Use these suggested exercises to increase your understanding of the topic. Set up your I/O Server as an Internet Server. Configure an Internet Display Client. Create automated login and multiple server systems.

Further Reading

Use the following references to assist your understanding of the topic. CitectSCADA Help Topic - CitectSCADA Internet Display Client. Citect Knowledge Base Article Q2751: What TCP/IP ports are used for the IDC client? Citect Knowledge Base Article Q2931: Trouble Free IDC.

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Web Client CitectSCADA through Internet Explorer

The CitectSCADA Web Client allows you to view a live CitectSCADA project within a Web browser. It provides easy access to CitectSCADA Runtime for LANconnected users requiring read/write access to current production information. The CitectSCADA Web Client Help has a procedural structure that is intended to guide you through the steps required to successfully set up a Web Client system. To ensure a successful installation, it is recommended that you initially familiarise yourself with the System architecture, and then work your way through the following topics, as they logically guide you though the set up process.

Stage

Description

Installation

Covers the hardware and software requirements, the process for installing the Web Server software, and an explanation of what gets installed.

Web Client user account types

Describes the different types of client accounts supported by the Web Server and their access rights.

Setting up Security

Describes how to prepare the Web Server for secure communication and how to set up client accounts.

Preparing a CitectSCADA project for deployment

Explains the adjustments that need to be made to a CitectSCADA project prior to deployment on the Web Server.

Configuring a deployment

Describes how to deploy a project on the Web Server, by identifying its source location and associated servers.

Implementing multiple language support

if required, there are several language options you can implement on the Web Server interface.

Frequently Asked Questions

If you have worked your way through the procedures outlined above and are still having problems, there is a Frequently Asked Questions section to help resolve some of the problems that may be encountered.

Suggested Exercises

Use these suggested exercises to increase your understanding of the topic. Set up a Web Server. Set up the Windows Security for the necessary Web Client Users. Deploy your Project. Connect using Internet Explorer. Attend a Citect Intermediate Networking Course where Web Client is examined in great detail.

Further Reading

Use the following references to assist your understanding of the topic. CitectSCADA Help Topic - CitectSCADA Web Client. All of it!

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Object IDs Validating Distributed Project Data for Tag-based Drivers

CitectSCADA uses numeric index values to uniquely identify all the variable tags in a project. They are used as a reference point when requesting data from the I/O server for a tag-based driver. These index values are automatically generated when a project is compiled, which means they need to be carefully monitored when running a project across a number of client and server machines. Circumstances may arise where a distributed project has index values that represent different tag addresses on different computers. For this reason, CitectSCADA has a number of automatic checks in place that validate a project's tag index values and flag any discrepancies. An initial security check takes place on client machines at a unit level, allowing a tag index mismatch to be isolated to a particular client before any requests are sent to the I/O Server. This confirms that the unit address, the unit type, the raw data type and the tag address match for all index values across the client and server machines. Any problems are flagged by a hardware alarm on the client machine. Each page is also checked to confirm that it was compiled against the current version of the variables database. There is also a check performed whenever a tagbased driver loads the variable database to ensure it matches the current tag addresses. The parameter TagAddressNoCase allows you to adjust the casesensitivity of these checks. In addition, CitectSCADA will also check if a project is currently running on the local machine when a compile is attempted, as this is one of the circumstances that may lead to mismatched index values. If the project uses a tag-based driver and is currently in runtime, CitectSCADA will stop the compiler and generate an error in the error database noting that Citect32.exe was still running. The .ini parameter [General]CitectRunningCheck allows you to override this feature, however it is recommended that you leave it enabled to ensure your tag index values remain valid.

Further Reading

Use the following references to assist your understanding of the topic. CitectSCADA Help Topic - [IOSERVER] parameters Citect Knowledge Base Article Q4074: OID Tag Based Drivers.

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Chapter 3:

Navigating the Knowledge Base

Overview Introduction

The Knowledge Base contains three navigational tools to help you quickly find relevant information: Contents - so you can always find the start and also lists the Latest Articles. Index - Lists all articles in numeric order Search - the quickest way to find relevant articles. It allows you to query all of the text in the entire Citect Knowledge Base.

This Chapter Covers These Topics: Searching................................................................................3-2

Searching Search Queries

Learning about effective queries will help you to locate relevant articles. The simplest query consists of just one word. For example, to find articles about alarm pages, you could enter the word alarm. This query would return a list of all articles that contain the word 'alarm'. If the query word is common, a large number of articles will be displayed, and you may need to further narrow your search.

Enter Multiple Words

To narrow your search, enter more than one word. For example, to find articles about alarm pages, you could enter the words alarm page. This query would return all articles that contain both the words 'alarm' and 'page'. Some search engines require the keyword AND to be used for this kind of search - it is not necessary here.

Operators

Customise your queries with the NEAR, NOT and OR keyword operators. For example, the query alarms page not hardware, would exclude an article about the "hardware alarms page".

Literal Phrases

Put quotation marks around keywords if you want to search for a literal expression. For example, searching for "alarm page" would find articles that contain that exact phrase. This can be quite useful if you need to use a keyword in your search. For example, "exclusive or" contains the keyword OR, and would cause an error without the quotes.

Wild Cards

Use wild cards (* and ?) where you are uncertain about the form of a word. For example, if you are uncertain about whether to search for "alarms", "alarm", or "alarming", search instead for alarm*. The ? is similar, but works only for one character.

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Appendix A: First Appendix

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