File Management, Virus Protection, and Backup

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File Management, Virus Protection, and Backup
File Basics
Section A
CHAPTER 4
PARSONS/OJA
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File Management, Virus Protection, and Backup
Chapter 4
Chapter PREVIEW

• Create valid names for files and folders
• Use file management features
• Describe how a computer physically stores files
• Explain viruses, boot sector viruses, macro
  viruses, Trojan horses, worms, and Denial of
  Service attacks
• Describe how antivirus software is used
• Understand backup and restore plans
• Compare backup devices

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File Basics
Section A
Chapter 4
Filenames, Extensions, and Formats What are
the rules for naming files?

• Every file has a name, and might also have a
  filename extension
• You must provide a valid filename that adheres to
  rules or file-naming conventions

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File Basics
Section A
Chapter 4
What are the rules for naming a file?
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File Basics
Section A
Chapter 4
Are filename extensions important?

• Filename extension further describes the file
  contents
• Separated by the filename with a dot
• Readme.txt, Newsletter.doc
• Related to the file format, the arrangement of
  data in a file, and the coding scheme used to
  represent the data
• Most software programs have a native file format
  that is used to store files
• They display any files that have the filename
  extension for its native file format

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File Basics
Section A
Chapter 4
Are filename extensions important?
Click to start
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File Basics
Section A
Chapter 4
File Locations, Folders, and Paths How do I
designate a files location?

• You first specify where file will be stored
• A for floppy disk drive
• C for hard drive
• D through Z for additional storage
• CD, Zip and DVD drive letters are not standardized

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File Basics
Section A
Chapter 4
Whats the purpose of folders?

• An operating system maintains a list of files
  called a directory for each disk, CD-ROM or DVD
• Folders - smaller lists within directories
• A folder is separated from a drive letter and a
  filename by a backslash (\)

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File Basics
Section A
Chapter 4
Whats the purpose of folders?

• A file specification (path) is the drive letter,
  folder, filename, and extension that identifies a
  file
• C\Music\Reggae\Marley One Love.mp3

drive letter
extension
filename
Primary Folder
Secondary Folder
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File Basics
Section A
Chapter 4
File Sizes and Dates. Sorting
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File Basics
Section A
Chapter 4
Is the file date important?

• Your computer keeps track of the date that a file
  was created or last modified
• The file date is useful if you have created
  several versions of a file and want to make sure
  that you know which version is the most recent

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File Management
Section B
Chapter 4
Whats the difference between the Save option
and the Save As option? Renaming fileSaving with
new name
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File Management
Section B
Chapter 4
What other options does the Save As dialog box
provide?

• You can use it to rename a file, delete a file,
  or create a folder

Click to start
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File Management
Section B
Chapter 4
File Management Utilities How does the
operating system help me manage files?

• File manager utility software
• provided by your computer operating system
• helps you locate, rename, move, copy and delete
  files

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File Management
Section B
Chapter 4
Windows Explorer How do I use a file
management utility?

• Windows Explorer is an example of a file
  management utility

Click to start
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File Management
Section B
Chapter 4
Is data stored in specific places on a disk?
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File Management
Section B
Chapter 4
How does a disk get formatted? Malfunctioning
floppy disks

• Formatting utilities are supplied by operating
  system or by companies that manufacture the drives

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File Management
Section B
Chapter 4
How does the operating system keep track of a
files location?
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File Management
Section B
Chapter 4
What happens when a file is deleted?

• The OS simply changes the status of the files
  clusters to empty and removes the filename from
  the FAT. It doesnt remove the data, just the
  references to it
• Special file shredder software can be used to
  overwrite empty sectors with random 1s and 0s
• Helpful if you want to make sure that your
  personal data no longer remains on the hard disk
• Individual bought 158 used hard drives on EBAY
  just to obtain personal info on them
• Tax returns, 3,700 credit card numbers, bank
  account numbers, legal and medical records
• Only 12 were properly purged
• What happens when you put your computer in the
  trash???
• Europe requires recycling
• 63 million PCs placed in U.S. landfills in 2003

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File Management
Section B
Chapter 4
How does the Recycle Bin affect file deletions?

• Deleted files are moved to the Recycle Bin folder
• Helps to protect against accidental erasures
• Can you retrieve files from the Recycle Bin???

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File Management
Section B
Chapter 4
How does a disk become fragmented?

• As computer files are added/deleted, parts of
  files tend to become scattered all over the disk
• These fragmented files are stored in
  noncontiguous clusters
• Slows drive performance
• Defragmentation utility rearranges the files on
  a disk so that they are stored in contiguous
  clusters.

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File Management
Section B
Chapter 4
How does a disk become fragmented?
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Computer Viruses
Section C
Chapter 4
Viruses, Trojan Horses, and Worms Whats the
technical definition of a virus?

• A computer virus is a program that attaches
  itself to a file, reproduces itself, and spreads
  to other files
• A virus can perform a trigger event
• corrupt and/or destroy data
• display an irritating message
• Key characteristic is their ability to lurk in
  a computer for days or months quietly replicating
  themselves

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Computer Viruses
Section C
Chapter 4
Whats the technical definition of a virus?

• File virus - a virus that attaches itself to an
  application program
• Chernobyl - designed to lurk in computer until
  April 26
• A boot sector virus infects the system files that
  your computer uses every time you turn it on.
• Computer lab.
• A macro virus infects a set of instructions
  called a macro.
• Macro - a miniature program that usually contains
  legitimate instructions to automate document and
  worksheet production
• File attachments

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Computer Viruses
Section C
Chapter 4
How is a Trojan horse different from a virus?

• A modern day Trojan horse is a computer program
  that appears to perform one function while
  actually doing something else
• Not a virus, but may carry a virus
• Does not replicate itself
• Another type of Trojan horse looks like a log-in
  screen
• PictureNote.Trojan arrives as e-mail named
  picture.exe and then tries to steal login and
  e-mail passwords

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Computer Viruses
Section C
Chapter 4
Whats a worm?

• A software worm is a program designed to enter a
  computer system through security holes
• usually through a network
• does not need to be attached to a document to
  reproduce
• 8/03 Blaster worm attacks Air Canadas
  reservation system
• Denial of Service attacks

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Computer Viruses
Section C
Chapter 4
How are viruses spread?
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Computer Viruses
Section C
Chapter 4
How are viruses spread?

• Viruses are spread through e-mails as well
• 8/03 SoBig Virus
• Placed virus on pc which sent e-mail to everyone
  in your address book with virus attached
• Shut down CSX rail system
• Macro viruses are usually found in MS Word and MS
  Excel files (.doc and .xls)
• To keep safe, you can disable macros on files you
  do not trust

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Computer Viruses
Section C
Chapter 4
What are the symptoms of a virus?

• Your computer displays a vulgar, embarrassing or
  annoying message
• Your computer develops unusual visual or sound
  effects
• You have difficulty saving files files
  mysteriously disappear
• Your computer reboots suddenly
• Your computer works very slowly
• Your executable files unaccountably increase in
  size
• Your computer starts sending out lots of e-mail
  messages on its own

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Computer Viruses
Section C
Chapter 4
Too much Microsoft.

• 95 of operating system software designed by
  Microsoft
• If hackers can find a flaw in this software they
  can utilize this to impact many computers, not
  just a few.
• If we used several different operating systems
  creating viruses would not be so much fun
• Recently a panel of experts called Microsofts
  dominance of the software market a national
  security concern

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Computer Viruses
Section C
Chapter 4
Antivirus Software Whats antivirus software?

• Antivirus software is a set of utility programs
  that looks for and eradicates a wide spectrum of
  problems such as viruses, Trojan horses, and worms

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Computer Viruses
Section C
Chapter 4
How does antivirus software work?

• Hackers have created viruses that can insert
  themselves into unused portions of a program.
• To counterattack the work of hackers, antivirus
  software designers created software with a
  checksum - a number calculated by combining
  binary values of all bytes in a file
• compares checksum each time you run a program

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Computer Viruses
Section C
Chapter 4
How does antivirus software work?

• Antivirus software also checks for a virus
  signature a unique series of bytes used to
  identify a known virus

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Computer Viruses
Section C
Chapter 4
When should I use antivirus software?

• All the time
• Does slow machine performance
• Most antivirus software allows you to specify
  what to check and when to check it
• Norton Antivirus
• McAfee Antivirus

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Computer Viruses
Section C
Chapter 4
How often should I get an update?

• New viruses and variations of old viruses are
  unleashed just about everyday
• Check website of antivirus software publisher for
  periodic updates
• Software can be set to update itself
  automatically. This is what you want
• Must also keep your operating system up to date
  with patches prepared by Microsoft
• And if you have a home network, you need a
  firewall

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Data Backup
Section D
Chapter 4
Backup and Restore Procedures How do I make a
backup?

• Data backup, a copy of a file or the contents of
  a disk drive, provide the best all-round security
  for your data
• A backup is usually stored on a different storage
  medium from the original files
• The exact steps that you follow depend on your
  backup equipment, your backup software, and your
  personal backup plan
• Data rewind

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Data Backup
Section D
Chapter 4
How do I restore data?

• You restore data from a backup to the original
  storage medium or its replacement

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Data Backup
Section D
Chapter 4
Whats the best backup plan?
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Data Backup
Section D
Chapter 4
Do I have to back up every file?

• Not necessarily, you could just back up most
  important files such as your data files
• Best is to select a strategy
• Store data files in specific location. Offsite!
• Also backup
• Internet connection information
• E-mail folders
• E-mail address book
• Favorite URLs
• Downloads

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Data Backup
Section D
Chapter 4
How often should I back up my data?

• Backup your data depending upon how much data you
  can afford to use
• Under normal use, once-a-week should be good
  enough

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Data Backup
Section D
Chapter 4
How many sets of backups do I need?

• One backup is good, but in case your backup gets
  corrupted, you should maintain a rotating set of
  backups

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Data Backup
Section D
Chapter 4
Will all of my backups contain the same files?

• Full backup - copy of all files on a disk safe
  but can take a long time
• computer cannot be used during backup
• backup device requires equal capacity
• Differential backup - copy of all files that have
  changed since the last full backup
• takes less time but more complex
• requires one full backup and then you will make
  differential backups at regular intervals

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Data Backup
Section D
Chapter 4
Will all of my backups contain the same files?

• Incremental backup - copy of all files that have
  changed since the last backup
• not necessarily since the last full backup, but
  since any previous backup
• takes the least time but is most complex to
  restore
• requires good recordkeeping
• label correctly

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Data Backup
Section D
Chapter 4
How can I make sure that my backups will work?

• Test your backups periodically

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Data Backup
Section D
Chapter 4
Do I need a boot disk?

• A boot disk is a floppy disk or CD that contains
  the OS files needed to boot your computer without
  using hard drive
• Most manufacturers include a recovery CD for
  restoring your system to original setup
• Windows Startup Disk it loads OS, and the
  CD-ROM drivers necessary for your computer to
  access files on the CD-ROM
• Antivirus software creates rescue disk with boot
  info and antivirus software

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Data Backup
Section D
Chapter 4
Can I store my backups on the Internet?

• Several web sites offer fee-based backup storage
  space
• When needed, you simply download backup files
  from the Web onto your hard disk
• Definitely offsite storage
• But what if they go out of business???

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Data Backup
Section D
Chapter 4
Do floppy disks and Zip disks play any role in
backups?

• Floppy disks are inexpensive, contain 1.44 MB
  space, and are good for several documents
• Zip disks 100 MB and 250 MB capacity is
  sufficient for documents and digital graphics

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Data Backup
Section D
Chapter 4
What about writable CDs and DVDs?

• Writable optical technologies provide good
  storage capacity and blank disks are fairly
  inexpensive

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Data Backup
Section D
Chapter 4
How about a second hard disk drive?

• Good backup option
• Disadvantage susceptible to same dangers of
  first drive
• Fire, theft, etc.

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Data Backup
Section D
Chapter 4
How do I choose a backup device? What about
flash drives??? 128 MB
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Data Backup
Section D
Chapter 4
Backup Software Do I need special software to
make a backup?

• Software depends on your backup plan
• Can use your file management utility to do simple
  file copying backup software are available

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Data Backup
Section D
Chapter 4
Whats the easiest way to make a copy of a
floppy disk?

• Many personal computer OSs provide a Copy Disk
  Utility
• Makes copies of floppy disks only

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Data Backup
Section D
Chapter 4
Whats the easiest way to make a copy of a
floppy disk?
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