Tài liệu Part-3 living online

Living Online Using Windows XP IC3 Module C — Courseware 1118-1 © CCI LEARNING SOLUTIONS INC. LIVING ONLINE 1103-0C ii MODULE C: PREFACE Preface This courseware is one in a series prepared by CCI Learning Solutions Inc. for use by students and instructors in courses on computer software applications. CCI designed these materials to assist students and instructors in making the learning process both effective and enjoyable. CCI Learning Solutions Inc. would like to acknowledge the contributions of the instructors and consultants who have worked with CCI Learning Solutions Inc. for their participation in the development of this courseware. We acknowledge the financial support of the Government of Canada through the Book Publishing Industry Development Program for our publishing activities. In providing this courseware for the use of students and instructors, CCI does not intend to replace the user’s manuals and other documentation supplied by the software manufacturer. The manufacturer’s documentation covers topics in more detail than this courseware, and the material CCI provides is based on interpretation of available information at the time of publication. It is therefore subject to change. Courseware Developer & Managing Editor Publishing Manager Sue Wong Kelly Hegedus Technical Editor, Cover Design Grammatical Proofreader Bob Garnett Lorraine Ambrosio No portion of this document may be reproduced, stored in a retrieval system, or transmitted, in any form or by any means, electronic, mechanical, or otherwise, without the prior written permission of CCI Learning Solutions Inc. The information in this courseware is distributed on an “as is” basis, without warranty. While every precaution has been taken in the preparation of this courseware, neither the author nor CCI Learning Solutions Inc. shall have any liability to any person or entity with respect to any liability, loss, or damage caused or alleged to be caused directly or indirectly by the instructions contained in this courseware or by the computer software and hardware products described therein. Any other brand name or product mentioned in this publication is a trademark or registered trademark of their respective companies and are used for identification purposes only. CCI Learning Solutions Inc. Copyright 2002, 2003, 2004 CCI Learning Solutions Inc. United States: 1-888-997-4224 ISBN: 1-55332-071-9 Canada: 1-800-668-1669 All rights reserved. www.ccilearning.com Printed in Canada. The exercises in this courseware require you to use the data files provided for the book. The data files can be downloaded from http://www.ccilearning.com/data. Complete instructions on how to download the files are located on page viii. LIVING ONLINE 1118-1 © CCI LEARNING SOLUTIONS INC. About This Courseware Approved by Certiport We are pleased to announce that our courseware has been approved for the IC³ Certification. This book fulfills the basic requirements for the Living Online IC³ exam; please refer to the IC³ Courseware Mapping at the back of our book to see where the features are covered. What this means is that after completing the exercises in this book, the user could be prepared to take the Living Online IC³ exam for the Internet and Computing Core Certification Program. Passing these exams demonstrates a level of proficiency to employers and customers. The exams are available through participating IQ test centers. IC³ . . . What Is It? IC³, or the Internet and Computing Core Certification program, is a global training and certification program providing proof to the world that you are: ƒ Equipped with the needed computer skills to excel in a digital world. ƒ Capable of using a broad range of computer technology – from basic hardware and software, to operating systems, applications and the internet. ƒ Ready for what the work employers, colleges and universities want to throw your way. ƒ Positioned to advance your career through additional computer certifications such as CompTIA’s A+, and other desktop application exams. IC³ . . . Why Do You Need It? Employers, Colleges and Universities now understand that exposure to computers does not equal understanding computers. So, more than ever, basic computer and Internet skills are being considered prerequisites for employment and higher education. This is Where IC³ Helps! IC³provides specific guidelines for the knowledge and skills required to be a functional user of computer hardware, software, networks, and the Internet. It does this through three exams: ƒ Computing Fundamentals ƒ Key Applications ƒ Living Online By passing the three IC³exams, you have initiated yourself into today’s digital world. You have also given yourself a globally accepted and validated credential that provides the proof employers or higher education institutions need. To learn more about IC³, visit www.certiport.com/ic3 To find a testing center near you, visit www.certiport.com/iQcenterLocator About Certiport: Certiport, Inc. is the leading provider of global, performance-based certification programs and services designed to enable individual success and lifetime advancement through certification. For more information about Certiport’s offerings, visit www.certiport.com Note: Certiport is a registered trademark of Certiport, Inc. in the United States and other countries. © CCI LEARNING SOLUTIONS INC. LIVING ONLINE 1118-1 Table of Contents Preface About This Courseware .................................................iii Table of Contents .......................................................... iv Courseware Conventions ............................................... vi Courseware Setup......................................................... vii Working With the Data Files ....................................... viii Unit 1: Getting Connected Lesson 1: Networking Fundamentals Objectives....................................................................... 2 What is a Network? ........................................................ 2 Where the Personal Computer Fits.................................. 3 Networking Standards .................................................... 3 Connecting to a Network ................................................ 6 Benefits of Networking................................................... 9 Disadvantages of Networking ....................................... 11 Summary ...................................................................... 14 Review Questions......................................................... 14 Lesson 2: Looking at the Internet Objectives..................................................................... 15 Introducing the Internet ................................................ 15 Connecting to the Internet............................................. 17 Recognizing Intranets and Extranets ............................. 22 Summary ...................................................................... 23 Review Questions......................................................... 24 Lesson 3: Understanding E-mail Fundamentals Objectives..................................................................... 25 What is Electronic Mail? .............................................. 25 Internal Mail................................................................. 26 Internet E-mail.............................................................. 26 Understanding an E-mail Address................................. 27 Looking at E-mail Message Components...................... 28 Using E-mail Options ................................................... 30 Using E-mail Appropriately.......................................... 34 Managing Spam............................................................ 37 Understanding Bad Netiquette ...................................... 38 Identifying Common E-mail Problems.......................... 39 Summary ...................................................................... 42 Review Questions......................................................... 42 Lesson 4: Using Microsoft Outlook Express Objectives .................................................................... 44 What is Outlook Express?............................................. 44 Using the Folder List .................................................... 46 Sending Messages ........................................................ 47 Receiving Messages ..................................................... 52 Attaching Files ............................................................. 55 Managing Messages ..................................................... 61 Sorting Messages.......................................................... 62 Working with the Address Book................................... 71 Performing Some Maintenance..................................... 76 Summary ...................................................................... 84 Review Questions......................................................... 85 Lesson 7: The Risks of Computing Objectives .................................................................. 178 LIVING ONLINE 1118-1 Unit 2: Using the Internet Lesson 1: Getting Started Objectives .................................................................... 88 Understanding Basic Terminology................................ 88 Understanding the World Wide Web ............................ 88 Using the Uniform Resource Locator (URL) ................ 90 Looking at the Home Page............................................ 91 Understanding the Domain Name Format..................... 92 Looking at Online Databases ........................................ 93 Identifying Other Elements........................................... 95 Summary ...................................................................... 97 Review Questions......................................................... 97 Lesson 2: Looking at Web Browsers Objectives .................................................................... 98 Using a Web Browser................................................... 98 Looking at Mailing Lists............................................. 104 Subscribing to a Newsgroup (Usenet)......................... 106 Summary .................................................................... 108 Review Questions....................................................... 108 Lesson 3: Using Microsoft Internet Explorer Objectives .................................................................. 110 Getting Started............................................................ 110 Looking at the Screen ................................................. 111 Summary .................................................................... 125 Review Questions....................................................... 126 Lesson 4: Using Information From the Web Objectives .................................................................. 127 Retrieving Information from a Web Page ................... 127 Printing a Web Page ................................................... 132 Downloading Information........................................... 136 Customizing the Web Browser ................................... 139 Summary .................................................................... 142 Review Questions....................................................... 142 Lesson 5: Searching for Information Objectives ................................................................. 143 “Surfing” the Internet ................................................. 143 Searching a Specific Web Site .................................... 144 Using Directories........................................................ 146 Using Portal Sites ....................................................... 148 Using Search Engine Technology ............................... 151 Narrowing the Search ................................................. 157 Using Boolean Terms ................................................. 161 Other Search Tools ..................................................... 166 Summary .................................................................... 168 Review Questions....................................................... 168 Lesson 6: Qualifying the Information Objectives .................................................................. 169 Evaluating the Information ......................................... 169 Having an Impact on Society ...................................... 171 Benefits of Using Computers...................................... 175 Summary .................................................................... 176 Review Questions....................................................... 176 Appendices © CCI LEARNING SOLUTIONS INC. Protecting Your Data or Computer ..............................178 Understanding Data Security.......................................179 Establishing a Safe Working Environment ..................180 Using Ergonomics.......................................................180 Understanding Viruses ................................................182 Performing a Data Backup ..........................................186 Summary.....................................................................187 Review Questions........................................................187 Appendix A: Productivity Tools..................................A-1 Appendix B: Glossary of Terms ..................................B-1 Appendix C: Index ......................................................C-1 Appendix D: Courseware Mapping ............................ D-1 Lesson 8: Accessing the Internet in a Legal & Safe Manner Objectives ..................................................................189 Restricting Access.......................................................189 Recognizing Copyright Issues .....................................190 Identifying Ethical Issues ............................................191 Protecting Yourself .....................................................193 Keeping Up with Technology......................................196 Looking at Personal Responsibilities ...........................196 Summary.....................................................................197 Review Questions........................................................198 © CCI LEARNING SOLUTIONS INC. LIVING ONLINE 1118-1 Courseware Conventions The following conventions are used throughout the courseware: ƒ ƒ ƒ ƒ ƒ ƒ ƒ Italic characters represent terms. Bold characters represent menu options, menu choices or toolbar buttons. The word “type” means to type: the indicated text The text set in this typeface indicates text to be typed, for example the save as file name. The word “press” means to press the specified . Instructions for exercises are in numbered steps. The instructions throughout this courseware assume that you will be using a mouse. Exercise text meant to be typed is typeset in this font. The Paragraph symbol (¶) is used to indicate pressing the key for the end of a paragraph or to leave a blank line.¶ Using the Book Course Length: This book contains information to cover all the objectives in the certification program, with a number of exercises designed so that you can emphasize and reinforce concepts. It has been designed to fit within a 15 to 20 hour course. Suggested timings have been provided with each lesson as a guide; this will vary depending on the size of your class, the experience or skill level, and the number of tools you may have available for specific topics. Step by Step Process: Each concept covered in an application module has an accompanying step by step exercise to demonstrate how the feature works. The exercises take users through each step of the process to accomplish the task, with appropriate screen captures to show the progress. This book provides a variety of ways to complete a task. Whenever you see this symbol, it shows another method to complete that task or additional information you need to know about the feature or step. As you learn each feature, oftentimes there are hints or tips you can use to accomplish the task faster or more productively. Alternatively, this could be a warning or an extra point about the feature that may occur, depending on what is happening on the computer. Multiple Exercise Sets Our books provide a variety of exercises to teach a concept. These exercises are set up in the following method: Exercise Hands on, step by step exercises that guide students through procedures and commands. They are presented immediately following a topic explanation and provide basic instructions on the most productive method of using a feature. Š Practice Exercise Hands on, step by step guided exercises presented after an exercise. These exercises provide extra practice and reinforcement or may present an alternative method of completing a task. LIVING ONLINE 1118-1 © CCI LEARNING SOLUTIONS INC. Courseware Setup This courseware was developed using specific software and hardware configurations. In order to complete this courseware, you will require the following minimum requirements: Hardware Requirements ƒ 500 MHz or higher (1.2 GHz or higher recommended) ƒ ƒ ƒ ƒ 128 Mb RAM or higher (256 Mb or higher recommended) ƒ Printer (user must have access rights to print documents) 300 Mb or higher free space on the hard drive Mouse or other compatible pointing device 101 enhanced keyboard In order to fully recognize some of the components that make up a computer, it is preferable to have access to these actual components, wherever possible. Software Requirements ƒ ƒ ƒ Microsoft Windows XP Professional SP2 Microsoft Outlook Express 6.00.2900 or higher Microsoft Internet Explorer 6.0.2900 or higher If you are using a lower version of Windows XP, you may not have the same screens or options as noted in this courseware. The SP2 version of Windows XP has more and enhanced security features and as such, will limit or restrict some of the features discussed in this courseware for living online. The objectives outlined in each lesson can be achieved by properly using the material and exercises in this courseware, and by paying close attention to your instructor. You should not hesitate to ask questions if you have problems in working through the material. A computer can be made up of a variety of components, some of which are either not discussed in great detail or at all in this courseware. The objectives in the IC3 program are designed to provide you with the basic fundamental knowledge for working with computers and achieve a digital literacy competency. For more information about other computers or types of computers not discussed in this courseware, please speak to your instructor for additional resources you can access. Outlook Express and Internet Explorer are have more features than can be mastered in a single course. This courseware presents a tremendous amount of material in a simple, easy-to-learn format and was designed to teach digital literacy skills for living online. You should read ahead during the course; you should also reread regularly. This will increase your retention of important concepts and skills, and will help you cope with the size and power of these programs as you continue to learn. This courseware assumes and requires that you have a good working knowledge of the PC and Windows, as well as how to use a mouse and keyboard. The explanations in this courseware are based on the default settings established during the installation of the Microsoft Windows XP SP2 program. Your computer (or the computers in the classroom lab) may be configured differently. If so, please check with your instructor, or consult the Microsoft Windows User Guide or the Microsoft web site to change the setup. © CCI LEARNING SOLUTIONS INC. LIVING ONLINE 1118-1 Working With the Data Files The exercises in this courseware require you to use the data files provided for the book. In order to maximize the usage of these data files, it is recommended that you reserve a minimum of 50Mb of space on your hard drive (or network, as applicable). Follow these steps to download the Student Files from the CCI web site: 1 Navigate to http://www.ccilearning.com/data 2 Select the IC3 Module C Student Files 1118-1-student-data.exe file from the list of files. Click the Download button. 3 Click Open in the File Download dialog box. 4 In the Winzip Self-Extractor dialog box that appears, use the Browse button to specify the Windows Desktop as the location to unzip the file and click Unzip. 5 The IC3 Mod C Files folder, containing the required Student work files, has now been downloaded to your desktop. You can reinstall and use the work files as many times as you like. All student data files have been checked for viruses at the time of development. The courseware developer is not responsible for any virus infection that may occur as a result of the customer or distribution channel manipulation. Please ensure your anti-virus software is current with the latest virus pattern to prevent new viruses from infecting the system. LIVING ONLINE 1118-1 © CCI LEARNING SOLUTIONS INC. Unit 1: Getting Connected This unit will introduce you to some of the common terminology and tasks associated with going “online”. You will begin with a look at what networks are, how they can connect you to others either in the office or off-site, and how to use e-mail to communicate. Lesson 1 2 3 4 © CCI LEARNING SOLUTIONS INC. Topic Networking Fundamentals Looking at the Internet Understanding E-mail Fundamentals Using Microsoft Outlook Express LIVING ONLINE 1118-1 2 USING THE INTERNET Lesson 1: Networking Fundamentals Objectives Suggested Timing: 1 Hour In this lesson you will look at what a network is and how it relates to “living online”. On successful completion, you will be familiar with the following concepts: ƒ What a network is ƒ Network standards ƒ Different types of networks ƒ What’s required to connect to a network ƒ Advantages and disadvantages of being connected to a network What is a Network? 1.1.1 1.1.2 A network in simple terms exists whenever two or more computers are connected together for the purpose of sharing resources and information. A network can be as small as two computers in a home, or as large as a company that has branches around the world. Living online refers to the process of being able to connect to the Internet and find information whenever it is needed. The Internet is a “living” network of resources where you can communicate with others online to find new, updated, or archival information. Resources Resource Local Area Network Internet User User User User As a user living online, you can access the many resources, as well as communicate with other users connected, via the Internet. A related scenario is the local area network (LAN). Many companies or organizations have an internal computer network that allows users to access internal company resources and to communicate with other employees. The LAN is typically also connected to the Internet. 1.1.3 Computers that connect to a network can be any type of computer from a mainframe to a PC or an Apple desktop or notebook to a PDA or cell phone. Each computer could be configured with a different operating system as well. There are no restrictions other than having the network software understand the protocol or rules and language needed to recognize the computer type and its operating system. For simplicity purpose in this courseware, we use the PC as our model for how a computer connects to a network. This model will reflect the standard guidelines for connecting any computer to a network, regardless of the type of computer it is; the differences will lie in the technology required to match the protocol needed to connect to a network such as notebook or desktop model, PC or Apple or mainframe, cable or wireless, etc. LIVING ONLINE 1118-1 © CCI LEARNING SOLUTIONS INC. 3 USING THE INTERNET Where the Personal Computer Fits 1.1.2 The personal computer (PC) is the most commonly used tool to connect to a network. Before dealing with networking, consider how the PC communicates with the outside world. The PC is shown schematically here: The microprocessor chip is the “brains” of the PC. It communicates with the other components (like the memory or the disk) of the PC via an internal connecting device called a “bus”. To communicate with external devices such as printers and scanners, the PC needs an interface card. Most PCs will have a number of empty “slots” where you can plug interface cards, depending on what types of external devices you intend to use. The interface cards have connectors that you can see at the back of your computer. If you want to connect your PC to a network, you need an interface card appropriate for the type of network, suitable cable, and appropriate software. Networking Standards 1.1.2 When you interconnect two or more computers so that they can communicate and share resources, you have established a network. Imagine attending a meeting where everybody spoke at the same time, in different languages, and about different subjects — confusion would reign! For meetings to be effective, they need to adhere to an agreed-upon protocol or set of rules. Protocols also make networking possible. There are rules governing the type of cables, interface cards, and electrical signal format. The Ethernet cabling standard is an example of this type of protocol and is very popular for office and home networks. There are also protocols governing how information will flow between computers on a network. These are called transport protocols which will determine: ƒ the way a computer indicates it needs to send information over the network ƒ how the receiving computer checks that the information was received correctly ƒ how the sending computer must address (label) the information so it goes to the correct destination computer Application level protocols determine how a program on one computer communicates with a program on another computer. An example of this is the browser program on your computer “talking” to the web program on the web server computer. They will “talk” using the hypertext transfer protocol (http). The basic concepts of networking are not very difficult to understand. The networking standards that have evolved since the introduction of the PC have made networking easier and more affordable. There are a number of different ways that networks can be set up and configured that go beyond the scope of this courseware. The most common types of networks are discussed here. © CCI LEARNING SOLUTIONS INC. LIVING ONLINE 1118-1 4 USING THE INTERNET Peer-to-Peer Networks 1.1.1 1.1.3 Peer-to-peer networks are inexpensive and easy to put together. They are ideal for home and small office networks. The network is called peer-to-peer because all computers have equal authority — no single computer controls the network. Any computer can share its resources (e.g., hard drive, printers, etc.) with other computers on the network. For example, computer C can declare its high speed color printer as a shared resource. Then when computer A wants to print a document, the high speed color printer will appear in the list of available printers almost as if it were connected directly to computer A. The peer-to-peer protocols were included starting with the Microsoft Windows 95/98/ME operating systems. There are also several proprietary peer-to-peer network systems available. Windows NT (or higher) has a network component built in that uses more complex protocols to connect computers. Client-Server Networks Client-Server networks are typical for larger networks. One computer, called the network server, is dedicated to controlling network traffic and managing the resources. 1.1.3 This type of network provides better performance and security than a peer-to-peer network because the server controls who can access what resources and when. It is also considered a central server as all files used by the company may be stored here for an employee to access from anywhere in the world. The server is called a network node. For instance, the above diagram is an example of a simple client-server network. Assume one user is in the Accounting department and the other is in the Warehouse. With the appropriate access to the server, both users can print their individual reports on the printer located at the back of the office on the second floor. They can also access a vacation request form designed for all employees stored on the server. The accounting software that both of these departments use is also installed on the server; however, the Accounting user may have access to all the modules of the accounting program whereas the Warehouse user may only have access to the Inventory module. The Disk object in the diagram might represent a backup device that performs a daily backup of all the company data, regardless of which department entered the information or when it was entered. Popular server network software systems include: ƒ ƒ ƒ Unix Novell Netware Microsoft Windows Server The server can essentially be a mainframe, minicomputer, Unix workstation or very powerful PC; it must also have the server software installed, with the users clearly identified and access rights set up. LIVING ONLINE 1118-1 © CCI LEARNING SOLUTIONS INC. USING THE INTERNET 5 The client computer can be any type of computer that has a network card and appropriate software to connect to recognize the server. Many larger companies have a mixture of PCs and Macintosh computers connected to their network; all users share the information from the same server even though the protocol to connect that computer to the server may differ. The sales people may also use notebooks with wireless network cards and be able to retrieve e-mail even though they are making customer visits outside of the office. LANs and WANs 1.1.2 What is the difference between a local area network (LAN) and a wide area network (WAN)? The same networking concepts discussed previously apply to both LANs and WANs. The difference lies in who is responsible for the cabling. A company or organization can do the network cabling within its own building, but are not allowed to install cabling that will cross a public street. That is the responsibility of the public authorities — usually the local telephone company. As long as a network stays within a building it is referred to as a LAN. If the network crosses a public street and makes use of publicly-supplied cabling for part of the network, it is referred to as a WAN. The following diagram shows two computers in different buildings connected in a network to form a simple WAN. All networks require additional network devices. These will be discussed shortly. When a computer or a LAN is connected to another computer or LAN in another city, or even another country, it becomes too complex to show the public portion of the WAN. It is frequently represented schematically by a “cloud”: The public network, or cloud, will consist of many nodes. © CCI LEARNING SOLUTIONS INC. LIVING ONLINE 1118-1 6 USING THE INTERNET Connecting to a Network 1.1.1 1.1.3 There are standard network devices that facilitate putting a network together. Even the cabling comes in standard lengths complete with appropriate connectors. So putting a network together is almost like connecting a number of “boxes” together. Which options, devices, or software you use depends on the needs and requirements for the network. The following information and diagrams discuss how a computer can be connected to a network that is within close distance to each other such as an office or home. You can also connect to a network via a modem such as connecting to the Internet from your home computer or from your Pocket PC. Connection/Cabling Options There is a variety of connection or cabling options available to access information to or from a network. Newer connection types allow the data to be transferred between a computer and the network to flow much faster; with the costs of these connection types dropping significantly, more people are choosing to either set up or switch to a faster connection method. Some of the more popular connection options include: Coaxial This is a wire with a center wire surrounded with insulation and then a grounded cover of braided wire to minimize electrical and radio frequency interference. This cable type used to be the main type of cable used for company networks or television transmission, with most company networks using Ethernet specifications in their network configuration. Fiber Optics A fiber optic cable is made up of bundled glass or plastic fibers (threads) to transmit data. This option is generally faster than coaxial cable as it has a much larger bandwidth for transmitting data and is much less susceptible to interference that occurs with metal cables. Broadband This type of data transmission is a single wire that can handle multiple paths or channels. These paths or channels are essentially from one connection to another. For example, the connection at the back of your computer is one end of a path and the network is the other end of that path; each computer in the company has its own channel to the network. Having a broadband connection allows a faster transmission of data as the network can then handle multiple channels at one time. Wireless This is quickly becoming the connection option of choice as it does not require any cables to be set in your home or office. There currently are three types of connections available for a specific use: cell phone, home, and office. In order to be connected in a wireless environment, each computer must have a network card with a wireless interface and an access point. Wireless devices work with radio frequencies for data transmission. Infrared This wireless option works with infrared light waves in order to transmit data. Some newer devices such as printers have an infrared device installed which then allows you to print a document to that printer provided you have an infrared wireless network card installed on your notebook. The one downside to using infrared is that the amount of distance between the two devices is less than using a wireless device that works with radio frequencies. The Network Interface Card (NIC) The PC talks to the external world via interface cards. To connect to a network, the PC must have a network interface card (NIC). Each NIC has a unique number or address and will have a connector (visible at the rear of the computer) that is appropriate for the type of cabling chosen. LIVING ONLINE 1118-1 © CCI LEARNING SOLUTIONS INC. 7 USING THE INTERNET Network cards come in a variety of styles and models that are appropriate for the computer type being connected to the network. Wireless PC NIC Internal PC NIC Wireless Apple Notebook NIC Wireless PC Notebook NIC Cell Phone NIC Wireless PDA NIC The Hub Hubs are used to connect PCs together to form a network. The diagram at the right shows a four port (connector) hub for a LAN. A cable from the NIC in each PC connects to a port on the hub. A cable from the hub will also be required to connect to the network. Hubs are relatively inexpensive to purchase and install. The main disadvantage of a hub is that all users connected to a hub share equal maximum transfer speed. For example, if the bandwidth (speed) of the network connection is 100 Megabits per second (Mbps), each user in this diagram would have a maximum connection speed of 25 Mbps. © CCI LEARNING SOLUTIONS INC. HUB Each port shares a portion of total Bandwidth LIVING ONLINE 1118-1 8 USING THE INTERNET Network Segments If a network has two (or more) network interface cards, each card is considered a segment. For example, if a company occupies more than three floors in a building, a segment may be set up for each department regardless of their location, for everyone on a particular floor, or the type of data that is processed on that floor. Segments allow network traffic to flow faster, depending on which devices are used to manage the amount of requests at the network. The Bridge A bridge is used to connect these network segments to handle network requests. Bridges do not analyze or re-route messages which makes receiving the information faster. However, a bridge will not reroute or re-transmit information if anything is wrong with the connection at either end, until it has received the first transmission completely. The Router Routers work similar to bridges except they examine the destination address of the information and pass it on the appropriate segment(s) only. For instance, when a message is received externally, when it reaches the network server, the router will analyze the message and route it to the appropriate recipients, if valid on the network. By the same token, if messages are sent externally via the Internet, the router will check to ensure the information is addressed correctly when leaving the server and forward it to the appropriate server to manage that message. Bridges may be faster than routers but as noted, they will not check the information coming in; the message coming in would be sent to everyone on the network, not just specific recipients. When installing a wireless router to your network, be sure to set up the encryption (password) security options to prevent unauthorized access from external sources using your connection to go online to the Internet. The Switch SWITCH A switch works similar to a hub except that each user connected to the switch has access to the full bandwidth. For instance, if the bandwidth was 100Mbits, every user on the switch would have a connection speed to the network of 100Mbits. Switches can also be used to join network segments. Each port uses the total Bandwidth LIVING ONLINE 1118-1 © CCI LEARNING SOLUTIONS INC. USING THE INTERNET 9 The Firewall The firewall can be a physical device or specialized software installed to prevent any unauthorized external access into any network that is connected to the Internet. The firewall is designed to check any messages that travel through the network and ensure it matches the specified security requirements (criteria) set up by the company. If the message does not meet those security requirements, it is then blocked from entering or exiting the network. This can be especially useful against any viruses attached to a message. The diagram here shows an example of firewall software that was installed on a computer dedicated for that purpose. Depending on the network configuration, the firewall software may be installed with the router or on individual computers (home computer). Benefits of Networking Networking does not make the individual workstations faster or more powerful! The benefits of networking fall into two main categories, communication and sharing of resources. 1.1.4 Communicating If you want to send information generated on a stand-alone PC to someone else, you would have to put the information on a portable disk. Then you would have to physically carry or mail the disk to the other person. By contrast, users on a network can send the information electronically. Another advantage of using networks for communicating is that a message can be stored on the network and is not lost if the recipient isn’t available at the time the message is sent. This is particularly useful when you need to communicate with a person in another time zone and don’t know when that person will connect to the Internet to retrieve their messages. This is much more cost efficient than calling long distance. For instance, you may want a progress report on how negotiations are going on a prospective deal in Europe as you would like to report on it in the Sales Meeting next Monday morning. You can send a message to the sales person in Europe requesting an update by Friday and they can send you a response within the next two days. This is less costly and time consuming than determining the appropriate time frame to call Europe and trying to reach the sales person directly. Many communication software programs contain a feature that allows users to instantly message someone else without having to use the electronic mail (e-mail) portion of the communication software. When using messages, you often do not get a response to the message until the recipient replies. Instant messaging allows for “real time interaction”, similar to having a conversation with someone in front of you. Provided all users are connected to the same network, multiple users can participate in the same conversation. This can be very advantageous when several users need to discuss the status of a project and each user is at a different location. There are some limitations of using instant messaging but these can be minor issues for being able to communicate with each other in real time. © CCI LEARNING SOLUTIONS INC. LIVING ONLINE 1118-1 10 USING THE INTERNET Sharing Devices Some devices like a high speed color printer or an all-in-one printer can be expensive to set up on every PC, especially if individual users will only need it occasionally. Networking allows such devices to be shared; this can be a cost savings to the company as they don’t need to buy a device for every system as well as saving time for technical support or maintenance. Connecting devices that need to be shared by multiple users via the network allows the network administrator to perform updates or troubleshoot problems from the server location. If further action is required, technical support can then move to the location where the actual equipment resides. Sharing Information When people work together, they need access to common information. In a stand-alone PC environment, the information has to be duplicated on every computer. This duplication leads to unnecessary work, potential errors and conflicts of version, i.e., which document is the latest valid version? In any network environment, files or folders on any disk can be set up to be shared by that user. Other users can then access that information (provided the user has turned on their PC). Whenever a group of people want to share information, it is referred to as a workgroup. This term is generally used for a group of users who need to share business documents although any group of users who need to share information for a workgroup will transfer or save their files to a common network. This common network then becomes a centralized server for those who need information stored on the network, e.g., business documents, software applications, templates, etc. As a central area for required resources, the server has control over which files are accessed and which users can use those files. This can assist to manage the files and number of requests from users on the network. A common network can be extremely helpful to the network administrator for setting up rights or performing maintenance for the workgroups. For instance, a workgroup can consist of all the sales and marketing staff who need access to the contact management database stored on the server. They also want access to the accounting program so they can input or check orders and run daily sales reports. Instead of having to set this up on every computer for all the sales and marketing staff, the network administrator can set up a workgroup with these staff member names and then assign rights to the appropriate software programs. Whenever one of these members logs in, they have the same rights as everyone else in that group. If a new employee is added to the Sales department, the network administrator needs only to add this new employee’s user name to the workgroup and they will automatically have the same access rights as any other sales member. Using Dedicated Servers A dedicated server is a computer that provides a specialized service. Because the server is dedicated to a specialized service, they can do the job better and faster than a general purpose PC. Such servers tend to be more expensive than regular PCs but this may be due to the specifications required to handle the task, e.g., very large hard drive, backup drive included, etc. The biggest advantage of dedicating a server for a specific purpose is that it allows anyone with proper access to this server to enter, view, manipulate, or print the information on this server. Network A client-server LAN uses a network server to control network traffic and security. The server manages the network and is referred to as the network node. Depending on the size of a company, the network server may also perform the same tasks and contain the same information as a file or database server. File A high speed, high capacity hard drive. The server is usually equipped with back-up facilities. File servers are used for the company’s common information or sensitive information that needs to be backed up regularly, e.g., designs for products, daily correspondence, etc. LIVING ONLINE 1118-1 © CCI LEARNING SOLUTIONS INC.