Click the Settings button to select programs, protocols, and services to be enabled for the
Chapter 17 ✦ Using E-Mail
use encryption with your e-mail messages, you must use digital IDs in conjunction with encryption. So the people in your address book must have a digital ID; you use their
public key to encrypt the messages. When the recipient gets the message, his or her private key decrypts it. And so it goes, back and forth, between the two of you.
Pretty Good Privacy PGP is a freeware program that uses public key authentication and encryption. PGP is a product of the PGP Corporation. Noncommercial U.S. citizens can obtain
PGP from many Web sites, including http:web.mit.edunetworkpgp.html. MIT’s Web site contains PGP for a variety of platforms. For more information about PGP, see
Chapter 22.
Using virus protection
Virus protection is most important with your e-mail program. E-mails with attachments come into your computer and your network and can damage and even destroy data and hardware.
You should definitely use a firewall to help screen out viruses see Chapter 16, but you should also use an antivirus program on each computer attached to the network.
Generally, viruses come in on the Internet or via e-mail. A virus could come in on a floppy disk brought from work or from your child’s school as well. So even if you don’t have an
Internet account, you should protect yourself from viruses. You can choose from many antivirus programs. Rather than downloading a free copy an
antivirus program, you would be much better served to purchase a copy of a program that is trusted and tested. Free antivirus programs do not usually let you update virus definitions to
catch the latest threats. Plus, free programs are not as meticulous at scanning your computer and protecting it.
Tip
Viruses, worms, and Trojan horses
Viruses come in different permutations, and they are constantly changing. Some people use the terms virus, worm, and Trojan horse interchangeably, but they are not the same thing. These
pests are designed to cause problems by people who know a lot about programming and have nothing better to do with their time.
✦ A
virus is a software program, script, or macro that propagates itself by infecting other
programs on the same computer. Viruses can destroy or damage a computer, data, or applications. Or a virus can just pop up an annoying window and do no damage. True
viruses cannot spread to another computer without your help, such as through trading files using a floppy disk or via an e-mail attachment.
✦ A
worm is a type of virus; it also propagates itself. A worm, however, can gain access to
the computer and travel across networks from one computer to the next, traveling on file-sending and -receiving features. It causes damage not only to the computer and soft-
ware but also to the network by deleting or modifying the data. ✦
A Trojan horse refers to a program you think you want, such as a free game, but it con-
tains something harmful. For example, you start the free game but find it erases every file in the directory. A Trojan horse could alternatively contain a virus or a worm, which then
spreads the damage.
Continued
Part IV ✦ Adding the Internet, E-Mail, and an Intranet
The best way to protect yourself against a virus is to install an antivirus program to all com- puters on the network and to keep the definitions updated. Definitions are fixes and identi-
fiers for new viruses being found every day. Norton AntiVirus is one of the best protections against threats, including viruses, worms,
and Trojan horses. Symantec, the maker of Norton AntiVirus, even offers a Web site where you can learn about viruses and find fixes to help clean viruses from your computer —
www.sarc.com. You can use this site and the fixes and information whether you buy the antivirus software or not.
Norton AntiVirus has many different versions and licenses. You can purchase the software to protect one machine — PC or Mac; you can purchase the software for a network with various
licenses for your users; you can purchase different versions that include personal firewall and other similar applications.
Continued For the purpose of the following discussion, the word virus will be used, but the information
applies to worms and Trojan horses as well. After a virus is created, it’s usually distributed through shareware, pirated software, or e-mail. The
virus infects one computer, starts destroying and damaging data, and then usually copies itself to other computers on the network.
Following are some interesting facts about viruses: ✦
Viruses can infect a computer even if files are just being copied. Viruses can open when you open an executable file a program file with an .EXE extension, for example.
✦ Some viruses can modify their own code as they spread, making various similar variants.
✦ A virus can be memory- or non-memory-resident. If the virus is memory-resident, it attaches
itself to the memory and then infects the computer. If it is non-memory-resident, that means you must run the virus program like double-clicking on an e-mail attachment in
order for it to run.
✦ A stealth virus attaches itself to files and then attacks the computer; stealth viruses
spread more quickly than other viruses. ✦
Viruses can remain on the computer even if the computer is formatted, for example, by infecting portions of the CMOS battery or master.
✦ Viruses usually attack EXE, COM, SYS, BIN, PIF, or any executable files. Viruses also like to
infect data files like those from Word or Excel. ✦
Viruses can increase in size without your even knowing they’re on your computer. ✦
Viruses can reboot the computer, delete files, change volume labels, cause hardware problems, disable ports, cause the system to hang or freeze, increase file size, display pic-
tures, and perform a host of other tasks you may never attribute to a virus.
Chapter 17 ✦ Using E-Mail
Norton AntiVirus not only removes viruses, but also it can scan incoming and outgoing mail, detect and block threats from instant messaging attachments, and enable you to update your
definitions daily. It has excellent technical help as well if you have problems with the software or with any virus. AntiVirus also has worm-blocking and script-blocking technologies to help
you protect your computer and your network. Norton cleans files, quarantines those it can’t clean, and even deletes infected files that are not appropriate to keep.
McAfee is another common and popular antivirus program. Like other products, McAfee offers a simple antivirus program or an entire suite of protection programs. McAfee does
include versions for Windows, Mac, and Linux, which might be of interest to those who use Linux. The McAfee program offers similar features to Norton, and the cost of the two is about
the same. It all depends on how many licenses you buy and what type of protection you want.
Other antivirus programs include Computer Associates’ EZ Antivirus, OLP eTrust Antivirus, and Internet Security Systems’ RealSecure.
Summary
In this chapter, you’ve learned how to set up e-mail on your local area network. You covered the following topics:
✦ Understanding e-mail
✦ Using the Inbox and other e-mail features
✦ Securing your computer and network e-mail
✦ Using various antivirus programs
In the next chapter, you learn about using chat programs.
✦ ✦
✦
Using Chat Programs
C
hat programs are popular for use over the Internet; however, they are also useful in your home network. You can send a mes-
sage upstairs to tell the kids that dinner is ready, for example, or you can send a quick message to your spouse to say the phone is for him
or her. Windows comes with a built-in chat program, but you can download several from the Internet as well.
Understanding Chat Programs
Chat programs enable you to talk to other people online, on the Internet, or on your own local area network. Chat programs involve
two or more people in a conversation in real time. Real time describes something that is happening right now. A phone conversa-
tion is in real time, for example, but a message on the answering machine is not.
There are Web-based chat programs, Internet Rely Chat IRC pro- grams, and instant messaging programs that you can use to chat over
the Internet. ✦
Web-based chat involves a plug-in mini-program that lets you chat with someone from your Web browser.
✦ You install IRC programs to your computer; then when you’re
online, you can participate in discussion groups. ✦
Instant messaging lets you set up a list of people to check when you’re online. If they are online too, you can send messages to
them and they receive the message instantly.
Using Internet instant messaging programs
Many popular Internet applications for instant messaging exist, including AOL Instant Messenger, ICQ, iChat Pager, and so on. You
install one of these programs on your computer, and then you can chat with anyone else who also has the program installed. Most chat
programs require the same program on the other end of the chat; ICQ, for example, isn’t compatible with iChat Pager. If you and a
friend use the same program, however, you can chat over the Internet anytime you’re both online.
18 18
C H A P T E R
✦ ✦
✦ ✦
In This Chapter
Understanding chat programs
Looking at WinPopup Looking at other
LAN chat programs Using instant messaging
✦ ✦
✦ ✦
Part IV ✦ Adding the Internet, E-Mail, and an Intranet
Some of these programs also have LAN options. Read the individual program’s documenta- tion or online help for more information.
Most of these programs start when you attach to the Internet. The program then operates in the background, waiting for you or one of your chat “buddies” to get online.
The manufacturer of the chat program assigns each person a code number like a telephone number. When you set up the program, you enter your friend’s numbers into the program.
The program monitors the Internet and detects when your chat buddy’s number appears online. The program notifies you that your buddy is online, and your buddy’s program noti-
fies him or her that you are online.
If you want, you can initiate a chat with your friend. You initiate a chat by sending a brief mes- sage asking if your friend would like to chat. Alternatively, your friend may send a message
asking you to chat. Some instant messaging programs, ICQ for example, let you talk to your friends, but you can
also meet other people online with the same interests as you. Most other programs are the same or similar. Figure 18-1 shows the Chatter Bug site. You can choose to search for people
by interest, location, or family, or you can do an advanced search by your own topics. If someone is online the same time you are, you can talk to them in an open discussion window
in real time.
You can also use message boards with most chat programs. Message boards aren’t instant; they are more like e-mail. You can read a message from someone and then reply to that mes-
sage, or you can create a new thread set of related messages of your own. Figure 18-2 shows the Chatter Bug Chat message board.
Figure 18-1: Chat with friends and make new ones.
Note
Chapter 18 ✦ Using Chat Programs
Figure 18-2: Message boards are another feature of Internet chat. Yahoo, AOL, Delphi, MSN, and other Web sites have Web-based chats available for free. You
must, however, register with the site to obtain admittance to these sites and chat rooms. You can choose a category of chat room to join, such as hobbies, computers, sports, art, and so
on. Then you choose from various chat rooms in that category, based on how many people are in the chat room.
Most chat rooms and message boards are safe to join, but you should not reveal any per- sonal information, such as your last name, phone number, or address. If you have children
who participate in Internet chats, you should keep a close check on their chat friends; after all, anyone can pretend to be someone else online.
Most IRCs, Web-based chats, and instant messaging programs have versions for the Macintosh as well as for Windows.
Using LAN instant messaging programs
In addition to Internet chat programs, LAN chat programs are available that you can use to communicate in real time with others on your LAN. You might wonder why you need to chat
over the computer when you’re in the same house as the other members of your network. LAN chats do not go out over the Internet; therefore, they are safer and more secure than
Internet chats. Plus, consider the convenience of online chatting over the network.
Note Caution
Part IV ✦ Adding the Internet, E-Mail, and an Intranet
Suppose that you’re upstairs working and you answer the phone. It’s for your spouse, who is working downstairs on the computer. Instead of running downstairs or yelling, you send a
quick message. WinPopup is a chat program that is included with the Windows 9598 operat- ing system, but the Windows 2000 and XP operating systems do not include the program. You
can, however, get a copy of the program from a shareware source, as described in the next section.
MacPopUp is a program that allows Windows users to send and receive messages from differ- ent operating systems, such as Mac OSs, Windows, Linux and UNIX OSs. MacPopUp is similar
to WinPopup. For instant messaging on your home network, you can use any of the free programs offered
by MSN, AOL, ICQ, and other Web-based messaging services. When you want to use an instant messaging program for your home use, you’ll still go over the Internet to connect. So
you’ll have to dial –up, or you can use a permanent connection, as with a cable modem.
When you want to communicate with another person in your household, or even a friend, you enter his or her assigned number. You can alternatively search for someone by e-mail address
or name. You send a message, and the recipient can either accept or decline the message. Then the other person can answer you. The conversation can go on and on.
You also can use a chat program to announce dinner, to ask someone to feed the cat or take out the garbage, or send a multitude of other requests. Additionally, you can hold longer con-
versations on a chat program. You might want to discuss a computer problem, an important decision about finances, or whether to let your kid borrow the car this weekend. Chat pro-
grams add to the convenience of working on computers and to being on the network.
LAN chat programs can help encourage office communications and collaboration. Users can quickly get answers to questions, query coworkers about contracts or invoices, and shoot
ideas back and forth by using a chat program.
A variety of LAN chat programs are available. You can purchase some programs that supply special features, such as file transfer capabilities, programmable Away messages messages
the program sends automatically when you’re away from the computer, and alarms for incoming messages. Other chat programs are shareware or freeware that offer basic services.
You can use ICQ, Yahoo, MSN, or other programs that are free.
Looking at LAN-Only Chat Programs
If you don’t have an Internet connection or you would prefer to not use an Internet messen- ger service, you can us a LAN-only chat program. Check www.shareware.com for shareware
or freeware you can use on your home network. Some programs that are useful include LAN Spirit, RealPopup, LANMessage, InterChat, WinPopup Gold, Windows Communicator, and
many more for Windows. For the Mac, you can try QuickPopup or SnapTalk. For Linux, try Vypress Messenger for Java. Most of these applications are free to try; many require a pay-
ment of 25 if you plan to use the application.
Using WinPopup Gold
The following information is about one of these programs — WinPopup Gold — but the instructions are similar to all of the LAN-only chat programs.
Small Business
Tip
Chapter 18 ✦ Using Chat Programs
Installing WinPopup Gold
You can acquire WinPopup Gold from various places on the Internet. CNET’s download.com is a great place for finding various shareware and freeware programs. After download, you
open the folder containing the WinPopup installation program and double-click the icon. Installation takes only a few minutes. WinPopup Gold works on all versions of Windows, but it
does not work on Macs and Linux machines.
To open WinPopup, you can put a shortcut on your desktop or you can go to Start ➪ Programs ➪ Smart Is On ➪ WinPopup Gold and click WinPopup Gold. Figure 18-3 shows the
WinPopup screen when you first open it.
Figure 18-3: WinPopup lets you send messages across your LAN.
Sending messages
To use WinPopup, you must start the program and leave it running. You can minimize the window so that it doesn’t interfere with your work. You can put a shortcut for the program in
your StartUp folder so it starts with Windows. You can send a message to one user by entering the user’s name or the computer name. You
can also click the Who Is Connected button to choose from someone who is on the network. You can even go to a chat room on the LAN, if you prefer.
To send a message, follow these steps: