Safe Computing, E-mail & Browser Tips

Gensoft - March 2001
by Allan Cole, DistGen Manager

Safe Computing

• More than 56,000 virus threats exist today
• Physical and Hacker Concerns

Parts to a virus program

• reproducing itself to spread
• timer/counter - when will it deliver its payload
• payload to be delivered

Types of Viruses:

• Boot viruses: place their code in the sector whose code the machine will automatically execute when booting. When the machine boots, they load and run. After they are finished loading, they load the original boot code, which they have previously moved to another location.
• File viruses: attach to executable program files in such a way that when you run the infected program, the virus code first executes. After the virus is finished loading and executing, it loads and executes the program it has infected.
• Macro viruses: attach their macros to templates and other files in such a way that, when an application loads the file and executes the instructions in it, the first instructions to execute are those of the virus.
• Companion viruses attach to the operating system, not files or sectors. In DOS, when you run a file named "ABC", ABC.COM would execute before ABC.EXE. A companion virus places its code in a COM file whose first name matches the name of an existing EXE. You run ABC, and the actual sequence is ABC.COM, ABC.EXE
• Worm: moves on the back of other files and tries to move from computer to computer and may contain all or just some of the parts of the above virus
• Trojan Horse: instantly delivers payload when run

Virus Information Libraries

• http://vil.nai.com/vil/default.asp
• www.symantec.com/avcenter/vinfodb.html
• http://www.ca.com/us/securityadvisor/virusinfo/

Virus Hoaxes

• http://vil.nai.com/VIL/hoaxes.asp
• www.symantec.com/avcenter/hoax.html
• Do not forward unconfirmed warnings.
• Don't let your guard down!
• Never open an email attachment unless you know what it is--even if it comes from someone you know and trust.
• Run a virus program and keep the data files up to date

Backups

• Make regular backups
• Be sure to keep 3 or more backup copies and rotate the backups
• To test the backups procedure, test you can actually restore from the backup

Magnetic Fields

Hackers

• Attack or snoop from the Internet
• Use a Firewall if using any of the high speed connections (Cable or ADSL)
• ZoneAlarm is a free firewall program for personal use

E-mail

Format

• xxx is the User ID
• @ is a separator
• yyyyy.zzzzz.ca is the Domain Name to which the Userid is registered

Purpose of Email

• Since the purpose of e-mail is to communicate, be sure that you are communicating
• Write in a manner that the reader will understand and is not offensive
• Use of shortcut notation is only to be used with people who understand such notation. Go to www.netdictionary.com/index.html for a shortcut dictionary if you get stuck on what someone put in a message to you. Some examples are: FYI (For You Information), IMHO (In My Humble Opinion), and AUP (Accepted Use Policy)

Using the Various E-mail Fields

• Separate email addresses with a comma if more than one email address is put in any of the To:, Cc: and Bcc: fields.
• To: is for the primary address(es) - may be used by itself or with the other fields
• Cc: is the Carbon Copy address(es) - may not be used alone, but must be used in conjunction with the To: and/or Bcc: fields
• Bcc: is the Blind Carbon Copy address(es) - may be used alone or with the To; and Cc: fields. A couple of examples:

Replying to e-mail

• The To field automatically is filled in with the sender of the original message and can be changed to what you wish.
• Delete the part of the original message not needed in the reply to cut down on useless information cluttering the message
• Keep the part of the message you will be replying to, to assure there is no mistaking the original questions wording

Forwarding e-mail

• The header information of the original message becomes part of the message.
• Add the email address of those who you are forwarding the message to
• Add whatever you wish to the message
• Delete those parts not wanted in the forwarded message

Filtering

• Filtering emails is useful to automate recursive actions, some of which might be:
• Delete spam
• Move emails to a specific folder
• Automate forwarding

Attachments are files to send with an email

• Pictures
• Documents, Databases, Spreadsheets and other files.
• Questions to consider:
  • Does the receiving computer have the software to use the incoming attachment.
  • Does the receiver really want the file
• Unfortunately attachments are sometimes used to spread viruses. Be very wary about opening an attachment. If you have a good virus program this is less of a problem.

Distribution Lists

• Lists of many email addresses to send a message to at the same time
• Requires you ask to have your name put on the list - subscribe to list
• Requires you ask to have your name removed from the list - unsubscribe from list
• Each list is usually associated with a specific topic
  • , Genealogy for Calgary and area researchers
  • http://lists.rootsweb.com/ - several genealogy lists

Browser Tips

Definition

Surfing the Net (Internet)

• Internet Explorer uses the Address field to input known addresses
• Netscape uses the Location field to input known addresses
• Web addresses or URLs can be found in Newspapers, Magazines, TV, Radio, Billboards... The URL (Universal Resource Locator) is the unique address on the Internet and is in the form www.calcna.ab.ca/ or http://198.161.243.11/
• Use the web pages and click on the various hot links until you find what you are looking for. These are usually colored differently to the rest of the text. The mouse will display a hand when it is pointing at a hot link.
• Use the search engines

Search Engines

• Browser's default search engine. Type keywords in the Address or Location field.
• Click on the Search button on the Toolbar
• Use one of the many search engines. Note that a search engine does not search the Internet, but in fact searches its own database for the requested information. It is therefore useful to try several search engines until you find what you're looking for. Some popular search engines are
• www.altavista.com/
• www.ask.com/
• http://www.dogpile.com/info.dogpl/
• www.excite.com/
• www.google.ca/
• www.hotbot.lycos.com/
• www.yahoo.com/

Downloads

• Be aware that some downloads are very large and will take some time to transmit
• Put the download in a logical place on your hard drive so you can find it later.
• Be sure that your virus protection is running before you open a download

Warnings

• Be sure you are where you want to be
• Ensure you are on a secure connection before giving personal or financial information
• Be especially careful about giving your credit card number
• Note - Be wary of the wording on some forms asking you to accept email:
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