Chapter 13:  Ensuring Integrity and Availability Network+ Guide to Networks
Objectives: <ul><li>Identify the characteristics of a network that keep data safe from loss or damage </li></ul><ul><li>Pr...
Objectives: (continued) <ul><li>Explain network- and system-level fault-tolerance techniques </li></ul><ul><li>Discuss iss...
What are Integrity and Availability? <ul><li>Integrity refers to the soundness of a network’s programs, data, services, de...
What are Integrity and Availability? (continued) <ul><li>General guidelines for protecting your network </li></ul><ul><ul>...
What are Integrity and Availability? (continued) <ul><ul><li>Monitor the network for unauthorized access or changes </li><...
What are Integrity and Availability? (continued) <ul><li>General guidelines for protecting your network (continued) </li><...
What are Integrity and Availability? (continued) <ul><ul><li>Keep backups, boot disks, and emergency repair disks current ...
Viruses <ul><li>A virus is a program that replicates itself with the intent to infect more computers </li></ul><ul><li>Oth...
Viruses (continued) <ul><li>Types of Viruses </li></ul><ul><ul><li>Boot sector viruses, Macro viruses, File-infected virus...
Viruses (continued) <ul><li>Virus Protection </li></ul><ul><ul><li>Antivirus Software </li></ul></ul><ul><ul><ul><li>Suspe...
Viruses (continued) <ul><li>Virus Protection </li></ul><ul><ul><li>Antivirus Software </li></ul></ul><ul><ul><ul><li>Antiv...
Viruses (continued) <ul><li>Virus Protection </li></ul><ul><ul><li>Antivirus Software </li></ul></ul><ul><ul><ul><li>Antiv...
Viruses (continued) <ul><li>Virus Protection </li></ul><ul><ul><li>Antivirus Policies </li></ul></ul><ul><ul><ul><li>Virus...
Viruses (continued) <ul><li>Virus Protection </li></ul><ul><ul><li>Antivirus Policies (continued) </li></ul></ul><ul><ul><...
Fault Tolerance <ul><li>The capacity for a system to continue performing despite an unexpected hardware or software malfun...
Fault Tolerance (continued) <ul><li>Environment </li></ul><ul><ul><li>Analyze the physical environment in which your devic...
Fault Tolerance (continued) <ul><li>Power (continued) </li></ul><ul><ul><li>Uninterruptible Power Supplies (UPSs) </li></u...
Fault Tolerance (continued)
Fault Tolerance (continued) <ul><li>Which UPS is right for your network </li></ul><ul><ul><li>Amount of power needed </li>...
Fault Tolerance (continued) <ul><li>Topology and Connectivity </li></ul><ul><ul><li>Each physical topology inherently assu...
Fault Tolerance (continued)
Fault Tolerance (continued)
Fault Tolerance (continued)
Fault Tolerance (continued)
Fault Tolerance (continued) <ul><li>Servers </li></ul><ul><ul><li>Server Mirroring </li></ul></ul><ul><ul><ul><li>Mirrorin...
Fault Tolerance (continued)
Fault Tolerance (continued) <ul><li>Servers </li></ul><ul><ul><li>Clustering </li></ul></ul><ul><ul><ul><li>Fault-toleranc...
Fault Tolerance (continued) <ul><li>Storage </li></ul><ul><ul><li>Redundant Array of Independent (or Inexpensive) Disks (R...
Fault Tolerance (continued) <ul><li>Storage </li></ul><ul><ul><li>RAID (continued) </li></ul></ul><ul><ul><ul><li>RAID Lev...
Fault Tolerance (continued)
Fault Tolerance (continued) <ul><li>Storage </li></ul><ul><ul><li>RAID (continued) </li></ul></ul><ul><ul><ul><li>RAID Lev...
Fault Tolerance (continued)
Fault Tolerance (continued) <ul><li>Storage </li></ul><ul><ul><li>RAID (continued) </li></ul></ul><ul><ul><ul><li>RAID Lev...
Fault Tolerance (continued)
Fault Tolerance (continued)
Fault Tolerance (continued) <ul><li>Storage </li></ul><ul><ul><li>RAID (continued) </li></ul></ul><ul><ul><ul><li>RAID Lev...
Fault Tolerance (continued)
Fault Tolerance (continued) <ul><li>Storage </li></ul><ul><ul><li>Network Attached Storage </li></ul></ul><ul><ul><ul><li>...
Fault Tolerance (continued)
Fault Tolerance (continued) <ul><li>Storage </li></ul><ul><ul><li>Storage Area Networks (SANs) </li></ul></ul><ul><ul><ul>...
Fault Tolerance (continued)
Data Backup <ul><li>A backup is a copy of data or program files created for archiving or safekeeping </li></ul><ul><li>Tap...
Data Backup (continued)
Data Backup (continued) <ul><ul><li>Tape Backups (continued) </li></ul></ul><ul><ul><ul><li>Select the appropriate tape ba...
Data Backup (continued) <ul><ul><li>Tape Backups (continued) </li></ul></ul><ul><ul><ul><li>Select the appropriate tape ba...
Data Backup (continued) <ul><li>Online Backups </li></ul><ul><ul><li>Companies on the Internet now offer to back up data o...
Data Backup (continued) <ul><li>Backup Strategy </li></ul><ul><ul><li>What data must be backed up </li></ul></ul><ul><ul><...
Data Backup (continued) <ul><li>Backup Strategy (continued) </li></ul><ul><ul><li>Where will backup media be stored </li><...
Data Backup (continued) <ul><li>Backup Strategy (continued) </li></ul><ul><ul><li>Different backup methods </li></ul></ul>...
Data Backup (continued)
Disaster Recovery <ul><li>A disaster recovery plan should identify a disaster recovery team </li></ul><ul><ul><li>Contact ...
Chapter Summary <ul><li>Integrity refers to the soundness of your network’s files, systems, and connections </li></ul><ul>...
Chapter Summary (continued) <ul><li>File-infected viruses attach themselves to executable files </li></ul><ul><li>Network ...
Chapter Summary (continued) <ul><li>Any type of virus may have additional characteristics that make it harder to detect an...
Chapter Summary (continued) <ul><li>A virus hoax is a false alert about a dangerous, new virus </li></ul><ul><li>A failure...
Chapter Summary (continued) <ul><li>A fault is the malfunction of one component of a system </li></ul><ul><li>Fault tolera...
Chapter Summary (continued) <ul><li>Networks cannot tolerate power loss or less than optimal power </li></ul><ul><li>A UPS...
Chapter Summary (continued) <ul><li>An online UPS uses the A/C power from the wall outlet to continuously charge its batte...
Chapter Summary (continued) <ul><li>Network topologies such as a full mesh WAN or a star-based LAN with a parallel backbon...
Chapter Summary (continued) <ul><li>Utilizing a second, identical server to duplicate the transactions and data storage of...
Chapter Summary (continued) <ul><li>An important storage redundancy feature is a Redundant Array of Independent (or Inexpe...
Chapter Summary (continued) <ul><li>A backup is a copy of data or program files created for archiving or safekeeping </li>...
Chapter Summary (continued) <ul><li>The aim of a good backup rotation scheme is to provide excellent data reliability </li...
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Chapter13 -- ensuring integrity and availability

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Chapter13 -- ensuring integrity and availability

  1. 1. Chapter 13: Ensuring Integrity and Availability Network+ Guide to Networks
  2. 2. Objectives: <ul><li>Identify the characteristics of a network that keep data safe from loss or damage </li></ul><ul><li>Protect an enterprise-wide network from viruses </li></ul>
  3. 3. Objectives: (continued) <ul><li>Explain network- and system-level fault-tolerance techniques </li></ul><ul><li>Discuss issues related to network backup and recovery strategies </li></ul><ul><li>Describe the components of a useful disaster recovery plan </li></ul>
  4. 4. What are Integrity and Availability? <ul><li>Integrity refers to the soundness of a network’s programs, data, services, devices, and connections. </li></ul><ul><li>Availability of a file or system refers to how consistently and reliably it can be accessed by authorized personnel </li></ul>
  5. 5. What are Integrity and Availability? (continued) <ul><li>General guidelines for protecting your network </li></ul><ul><ul><li>Allow only network administrators to create or modify NOS and application system files </li></ul></ul>
  6. 6. What are Integrity and Availability? (continued) <ul><ul><li>Monitor the network for unauthorized access or changes </li></ul></ul><ul><ul><li>Record authorized system changes in a change management system </li></ul></ul><ul><ul><li>Install redundant components </li></ul></ul>
  7. 7. What are Integrity and Availability? (continued) <ul><li>General guidelines for protecting your network (continued) </li></ul><ul><ul><li>Perform regular health checks on the network </li></ul></ul><ul><ul><li>Check system performance, error logs, and the system log book regularly </li></ul></ul>
  8. 8. What are Integrity and Availability? (continued) <ul><ul><li>Keep backups, boot disks, and emergency repair disks current and available </li></ul></ul><ul><ul><li>Implement and enforce security and disaster recovery policies </li></ul></ul>
  9. 9. Viruses <ul><li>A virus is a program that replicates itself with the intent to infect more computers </li></ul><ul><li>Other unwanted and potentially destructive programs are called viruses, but technically do not meet the criteria used to define a virus </li></ul><ul><ul><li>Program that disguises itself as something useful but actually harms your system is called a Trojan horse </li></ul></ul>
  10. 10. Viruses (continued) <ul><li>Types of Viruses </li></ul><ul><ul><li>Boot sector viruses, Macro viruses, File-infected viruses, Worms, Trojan horse, Network viruses, Bots </li></ul></ul><ul><li>Virus Characteristics </li></ul><ul><ul><li>Encryption, Stealth, Polymorphism, Time-dependence </li></ul></ul>
  11. 11. Viruses (continued) <ul><li>Virus Protection </li></ul><ul><ul><li>Antivirus Software </li></ul></ul><ul><ul><ul><li>Suspecting a virus </li></ul></ul></ul><ul><ul><ul><ul><li>Unexplained increases in file sizes </li></ul></ul></ul></ul><ul><ul><ul><ul><li>Significant, unexplained decline in system performance </li></ul></ul></ul></ul><ul><ul><ul><ul><li>Unusual error messages </li></ul></ul></ul></ul><ul><ul><ul><ul><li>Significant, unexpected loss of system memory </li></ul></ul></ul></ul><ul><ul><ul><ul><li>Fluctuations in display quality </li></ul></ul></ul></ul>
  12. 12. Viruses (continued) <ul><li>Virus Protection </li></ul><ul><ul><li>Antivirus Software </li></ul></ul><ul><ul><ul><li>Antivirus software should perform </li></ul></ul></ul><ul><ul><ul><ul><li>Signature scanning </li></ul></ul></ul></ul><ul><ul><ul><ul><li>Integrity checking </li></ul></ul></ul></ul><ul><ul><ul><ul><li>Monitoring of unexpected file changes </li></ul></ul></ul></ul>
  13. 13. Viruses (continued) <ul><li>Virus Protection </li></ul><ul><ul><li>Antivirus Software </li></ul></ul><ul><ul><ul><li>Antivirus software should perform (continued) </li></ul></ul></ul><ul><ul><ul><ul><li>Regular updates and modifications </li></ul></ul></ul></ul><ul><ul><ul><ul><li>Consistently report only valid viruses </li></ul></ul></ul></ul><ul><ul><ul><ul><ul><li>Heuristic scanning -- most fallible </li></ul></ul></ul></ul></ul>
  14. 14. Viruses (continued) <ul><li>Virus Protection </li></ul><ul><ul><li>Antivirus Policies </li></ul></ul><ul><ul><ul><li>Virus detection and cleaning software that regularly scans for viruses </li></ul></ul></ul><ul><ul><ul><li>Users not allowed to alter or disable </li></ul></ul></ul><ul><ul><ul><li>Users know what to do </li></ul></ul></ul><ul><ul><ul><li>Antivirus team appointed maintaining antivirus measures </li></ul></ul></ul>
  15. 15. Viruses (continued) <ul><li>Virus Protection </li></ul><ul><ul><li>Antivirus Policies (continued) </li></ul></ul><ul><ul><ul><li>Users prohibited from installing any unauthorized software </li></ul></ul></ul><ul><ul><ul><li>System-wide alerts issued </li></ul></ul></ul><ul><li>Virus Hoaxes </li></ul><ul><ul><li>Type of rumor consists of a false alert about a dangerous, new virus </li></ul></ul><ul><ul><li>Verify a possible hoax </li></ul></ul>
  16. 16. Fault Tolerance <ul><li>The capacity for a system to continue performing despite an unexpected hardware or software malfunction </li></ul><ul><ul><li>Failure is a deviation from a specified level of system performance for a given period of time </li></ul></ul><ul><ul><li>Fault involves the malfunction of one component of a system </li></ul></ul>
  17. 17. Fault Tolerance (continued) <ul><li>Environment </li></ul><ul><ul><li>Analyze the physical environment in which your devices operate </li></ul></ul><ul><li>Power </li></ul><ul><ul><li>Power Flaws </li></ul></ul><ul><ul><ul><li>Surge—A momentary increase in voltage </li></ul></ul></ul><ul><ul><ul><li>Noise—A fluctuation in voltage levels </li></ul></ul></ul><ul><ul><ul><li>Brownout—A momentary decrease in voltage </li></ul></ul></ul><ul><ul><ul><li>Blackout—A complete power loss </li></ul></ul></ul>
  18. 18. Fault Tolerance (continued) <ul><li>Power (continued) </li></ul><ul><ul><li>Uninterruptible Power Supplies (UPSs) </li></ul></ul><ul><ul><ul><li>Prevents A/C power from harming device or interrupting its services </li></ul></ul></ul><ul><ul><ul><ul><li>Standby UPS provides continuous voltage to a device by switching </li></ul></ul></ul></ul><ul><ul><ul><ul><li>Online UPS providing power to a network device through its battery </li></ul></ul></ul></ul>
  19. 19. Fault Tolerance (continued)
  20. 20. Fault Tolerance (continued) <ul><li>Which UPS is right for your network </li></ul><ul><ul><li>Amount of power needed </li></ul></ul><ul><ul><li>Period of time to keep a device running </li></ul></ul><ul><ul><li>Line conditioning </li></ul></ul><ul><ul><li>Cost </li></ul></ul><ul><li>Generators </li></ul><ul><ul><li>If your organization cannot withstand a power loss you might consider investing in an electrical generator for your building </li></ul></ul>
  21. 21. Fault Tolerance (continued) <ul><li>Topology and Connectivity </li></ul><ul><ul><li>Each physical topology inherently assumes certain advantages and disadvantages </li></ul></ul><ul><ul><li>Supplying multiple paths data can use to travel from any one point to another </li></ul></ul>
  22. 22. Fault Tolerance (continued)
  23. 23. Fault Tolerance (continued)
  24. 24. Fault Tolerance (continued)
  25. 25. Fault Tolerance (continued)
  26. 26. Fault Tolerance (continued) <ul><li>Servers </li></ul><ul><ul><li>Server Mirroring </li></ul></ul><ul><ul><ul><li>Mirroring is a fault-tolerance technique in which one device or component duplicates the activities of another </li></ul></ul></ul><ul><ul><ul><li>In server mirroring, one server continually duplicates the transactions and data storage of another </li></ul></ul></ul>
  27. 27. Fault Tolerance (continued)
  28. 28. Fault Tolerance (continued) <ul><li>Servers </li></ul><ul><ul><li>Clustering </li></ul></ul><ul><ul><ul><li>Fault-tolerance technique that links multiple servers together to act as a single server </li></ul></ul></ul>
  29. 29. Fault Tolerance (continued) <ul><li>Storage </li></ul><ul><ul><li>Redundant Array of Independent (or Inexpensive) Disks (RAID) </li></ul></ul><ul><ul><ul><li>Collection of disks that provide fault tolerance for shared data and applications </li></ul></ul></ul><ul><ul><ul><li>Hardware RAID </li></ul></ul></ul><ul><ul><ul><ul><li>Set of disks and a separate disk controller </li></ul></ul></ul></ul><ul><ul><ul><li>Software RAID </li></ul></ul></ul><ul><ul><ul><ul><li>Software to implement and control RAID </li></ul></ul></ul></ul>
  30. 30. Fault Tolerance (continued) <ul><li>Storage </li></ul><ul><ul><li>RAID (continued) </li></ul></ul><ul><ul><ul><li>RAID Level 0—Disk Striping RAID Level 0 </li></ul></ul></ul><ul><ul><ul><ul><li>data is written in 64 KB blocks equally across all disks in the array </li></ul></ul></ul></ul>
  31. 31. Fault Tolerance (continued)
  32. 32. Fault Tolerance (continued) <ul><li>Storage </li></ul><ul><ul><li>RAID (continued) </li></ul></ul><ul><ul><ul><li>RAID Level 1—Disk Mirroring RAID Level 1 </li></ul></ul></ul><ul><ul><ul><ul><li>provides redundancy through a process called disk mirroring </li></ul></ul></ul></ul>
  33. 33. Fault Tolerance (continued)
  34. 34. Fault Tolerance (continued) <ul><li>Storage </li></ul><ul><ul><li>RAID (continued) </li></ul></ul><ul><ul><ul><li>RAID Level 3—Disk Striping with Parity ECC RAID Level 3 </li></ul></ul></ul><ul><ul><ul><ul><li>Involves disk striping with a special error correction code (ECC) </li></ul></ul></ul></ul>
  35. 35. Fault Tolerance (continued)
  36. 36. Fault Tolerance (continued)
  37. 37. Fault Tolerance (continued) <ul><li>Storage </li></ul><ul><ul><li>RAID (continued) </li></ul></ul><ul><ul><ul><li>RAID Level 5—Disk Striping with Distributed Parity </li></ul></ul></ul><ul><ul><ul><ul><li>Highly fault-tolerant </li></ul></ul></ul></ul><ul><ul><ul><ul><li>Data is written in small blocks across several disks </li></ul></ul></ul></ul><ul><ul><ul><ul><li>Parity error checking information is distributed among the disks </li></ul></ul></ul></ul>
  38. 38. Fault Tolerance (continued)
  39. 39. Fault Tolerance (continued) <ul><li>Storage </li></ul><ul><ul><li>Network Attached Storage </li></ul></ul><ul><ul><ul><li>specialized storage device or group of storage devices that provides centralized fault-tolerant data storage for a network </li></ul></ul></ul>
  40. 40. Fault Tolerance (continued)
  41. 41. Fault Tolerance (continued) <ul><li>Storage </li></ul><ul><ul><li>Storage Area Networks (SANs) </li></ul></ul><ul><ul><ul><li>Distinct networks of storage devices that communicate directly with each other and with other networks </li></ul></ul></ul>
  42. 42. Fault Tolerance (continued)
  43. 43. Data Backup <ul><li>A backup is a copy of data or program files created for archiving or safekeeping </li></ul><ul><li>Tape Backups </li></ul><ul><ul><li>Copying data to a magnetic tape </li></ul></ul>
  44. 44. Data Backup (continued)
  45. 45. Data Backup (continued) <ul><ul><li>Tape Backups (continued) </li></ul></ul><ul><ul><ul><li>Select the appropriate tape backup solution </li></ul></ul></ul><ul><ul><ul><ul><li>Sufficient storage capacity </li></ul></ul></ul></ul><ul><ul><ul><ul><li>Proven to be reliable </li></ul></ul></ul></ul><ul><ul><ul><ul><li>Data error-checking techniques </li></ul></ul></ul></ul><ul><ul><ul><ul><li>Is the system quick enough </li></ul></ul></ul></ul>
  46. 46. Data Backup (continued) <ul><ul><li>Tape Backups (continued) </li></ul></ul><ul><ul><ul><li>Select the appropriate tape backup solution </li></ul></ul></ul><ul><ul><ul><ul><li>Tape drive, software, and media cost </li></ul></ul></ul></ul><ul><ul><ul><ul><li>Hardware and software be compatible with existing network </li></ul></ul></ul></ul><ul><ul><ul><ul><li>Frequent manual intervention </li></ul></ul></ul></ul><ul><ul><ul><ul><li>Accommodate your network’s growth </li></ul></ul></ul></ul>
  47. 47. Data Backup (continued) <ul><li>Online Backups </li></ul><ul><ul><li>Companies on the Internet now offer to back up data over the Internet </li></ul></ul>
  48. 48. Data Backup (continued) <ul><li>Backup Strategy </li></ul><ul><ul><li>What data must be backed up </li></ul></ul><ul><ul><li>What kind of rotation schedule </li></ul></ul><ul><ul><li>When will the backups occur </li></ul></ul><ul><ul><li>How will you verify </li></ul></ul>
  49. 49. Data Backup (continued) <ul><li>Backup Strategy (continued) </li></ul><ul><ul><li>Where will backup media be stored </li></ul></ul><ul><ul><li>Who will take responsibility </li></ul></ul><ul><ul><li>How long will you save backups </li></ul></ul><ul><ul><li>Where will backup and recovery documentation be stored </li></ul></ul>
  50. 50. Data Backup (continued) <ul><li>Backup Strategy (continued) </li></ul><ul><ul><li>Different backup methods </li></ul></ul><ul><ul><ul><li>Full backup </li></ul></ul></ul><ul><ul><ul><li>Incremental backup </li></ul></ul></ul><ul><ul><ul><li>Differential backup </li></ul></ul></ul>
  51. 51. Data Backup (continued)
  52. 52. Disaster Recovery <ul><li>A disaster recovery plan should identify a disaster recovery team </li></ul><ul><ul><li>Contact for emergency coordinators </li></ul></ul><ul><ul><li>Which data and servers are being backed up </li></ul></ul><ul><ul><li>Network topology, redundancy, and agreements </li></ul></ul><ul><ul><li>Regular strategies for testing </li></ul></ul><ul><ul><li>A plan for managing the crisis </li></ul></ul>
  53. 53. Chapter Summary <ul><li>Integrity refers to the soundness of your network’s files, systems, and connections </li></ul><ul><li>Several basic measures can be employed to protect data and systems </li></ul><ul><li>A virus is a program that replicates itself </li></ul><ul><li>Boot sector viruses position their code in the boot sector </li></ul><ul><li>Macro viruses take the form of a macro </li></ul>
  54. 54. Chapter Summary (continued) <ul><li>File-infected viruses attach themselves to executable files </li></ul><ul><li>Network viruses take advantage of network protocols </li></ul><ul><li>A virus bot is a virus that spreads automatically between systems </li></ul><ul><li>Worms are not technically viruses </li></ul><ul><li>A Trojan horse claims to do something useful but instead harms </li></ul>
  55. 55. Chapter Summary (continued) <ul><li>Any type of virus may have additional characteristics that make it harder to detect and eliminate </li></ul><ul><li>A good antivirus program should be able to detect viruses through signature scanning, integrity checking, and heuristic scanning </li></ul><ul><li>Antivirus software is merely one piece of the puzzle in protecting your network </li></ul>
  56. 56. Chapter Summary (continued) <ul><li>A virus hoax is a false alert about a dangerous, new virus </li></ul><ul><li>A failure is a deviation from a specified level of system performance for a given period of time </li></ul>
  57. 57. Chapter Summary (continued) <ul><li>A fault is the malfunction of one component of a system </li></ul><ul><li>Fault tolerance is a system’s capacity to continue performing despite an unexpected hardware or software malfunction </li></ul>
  58. 58. Chapter Summary (continued) <ul><li>Networks cannot tolerate power loss or less than optimal power </li></ul><ul><li>A UPS is a battery power source directly attached to one or more devices and to a power supply </li></ul><ul><li>A standby UPS provides continuous voltage to a device by switching </li></ul>
  59. 59. Chapter Summary (continued) <ul><li>An online UPS uses the A/C power from the wall outlet to continuously charge its battery </li></ul><ul><li>For utmost fault tolerance in power supply, a generator is necessary </li></ul>
  60. 60. Chapter Summary (continued) <ul><li>Network topologies such as a full mesh WAN or a star-based LAN with a parallel backbone offer the greatest fault tolerance </li></ul><ul><li>Hot swappable components can be changed (or swapped) while a machine is still running (hot) </li></ul><ul><li>Critical servers often contain redundant components </li></ul>
  61. 61. Chapter Summary (continued) <ul><li>Utilizing a second, identical server to duplicate the transactions and data storage of one server is called server mirroring </li></ul><ul><li>Server clustering links multiple servers together to act as a single server </li></ul>
  62. 62. Chapter Summary (continued) <ul><li>An important storage redundancy feature is a Redundant Array of Independent (or Inexpensive) Disks (RAID) </li></ul><ul><li>Network attached storage (NAS) is a dedicated storage device </li></ul><ul><li>A storage area network (SAN) is a distinct network of multiple storage devices and servers </li></ul>
  63. 63. Chapter Summary (continued) <ul><li>A backup is a copy of data or program files created for archiving or safekeeping </li></ul><ul><li>A popular, economical method for backing up networked systems is tape backup </li></ul><ul><li>You can also back up data over the Internet </li></ul>
  64. 64. Chapter Summary (continued) <ul><li>The aim of a good backup rotation scheme is to provide excellent data reliability </li></ul><ul><li>Every organization should have a disaster recovery team </li></ul>
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