Internet%20Security

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Internet Security

• facilities for secure communication

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MALWARE

• Malware refers to any program or computer code
  deliberately designed to harm any portion of a
  computer system
• The three most common forms of malware are
  viruses are viruses, worms and trojan horses
• Morris worm was created in 1988 and infected
  6,000 computers using the UNIX operation system.

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MALWARE COUNTERMEASURES

• Antivirus
• Signature scanning a virus signature is a string
  of binary code unique to a particular virus.
  Virus signatures are also known as fingerprints
  or patterns. Because new viruses appear all the
  time, a virus programs signature file must be
  updated frequently to maintain the programs
  ability to defend against threats. Many antivirus
  programs will automatically inform users when a
  new virus signature update is available for
  download.

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• Disadvantages of signature scanning
• Polymorphic viruses change with each replication.
  The constantly changing signature of a
  polymorphic virus makes it more difficult to
  detect using signature files alone.
• Signature scanning also is ineffective against
  new viruses for which signature updates do not
  yet exist
• It detects malware only after it has infected a
  computer system

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• Heuristic scanning looks for general malware
  characteristics rather than specific
  characteristics such as a signature.
• Heuristic problem solving relies on previous
  experience or knowledge.
• An antivirus program that uses heuristic scanning
  examines file size, architecture, or code
  behavior.
• Heuristic scanning can produce false positives
  and negatives.

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• For e.g.. It might report a legitimate software
  program as malware on the basis that it shares
  some characteristics with known malware programs.
  
• Just as with signature scanning, heuristic
  scanning software requires periodic updates to
  ensure that the catalog of suspicious
  characteristics is up to date.

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• Behavior Blocking looks for typical malware
  behaviors, such as attempts to change computer
  settings, the opening and or alteration of files,
  attempts to open computer ports etc.
• Ports are computer doorways used for various
  activities, and an open or unguarded port can be
  the entryway for malware.
• It is becoming popular since hackers face greater
  difficulty changing the behavior of malware than
  changing a virus signature

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FIREWALLS

• It is a hardware or software barrier located
  between the internet and a computer or computer
  network. Many routers available nowadays contain
  built-in firewalls
• A firewall is a system of hardware and software
  that connects the intranet to external networks,
  such as the internet. It blocks unauthorized
  traffic from entering the intranet and cal also
  prevent unauthorized employees from access the
  intranet

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• Two components of firewalls are a proxy server
  and caching.
• Proxy server is a server, or remote computer,
  that may exist outside of the organizations
  network, ad all communications to the
  organization are routed through it. The proxy
  server decides which messages or files are safe
  to pass through to the organizations network. It
  can also provide document caching

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• Caching is to store copies of web pages for quick
  access the purpose is to speed up the web for
  their users. The only difficulty with this
  practice is that the original web page may have
  been updated, but this is not reflected on the
  copy in the cache in the proxy computer.

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Firewalls

• Routers available nowadays contain built-in
  firewalls.
• A firewall filters data arriving through the
  internet to protect the system from any threats.
• Firewalls can be configured to reject incoming
  packets based on the IP address or domain name
  they originate from.
• This prevents the entry of data from sites known
  to harbor threats.

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Firewall

• A user can configure a firewall to allow or
  disallow the use of different protocols e.g.
  restricting FTP to prevent unauthorized file
  transfers from taking place.
• Firewalls can also filter incoming packets for
  text they might contain.
• Start with the highest level of security when you
  configure a firewall. If it creates problems
  denying access to legitimate data, adjust the
  configuration until an appropriate balance
  between security and convenience is achieved

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• Firewalls can help prevent malware but antivirus
  are also needed.

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Service Patches and updates

• Its important to install security patches.

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Password protection

• Passwords help protect your computers

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CYBER CRIME

• It refers to crimes committed using the internet.
• Some cyber crimes are phishing/spoofing, 419
  scams, DOS attacks, brute force attacks

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Phishing

• It is when an online scammer sends a user an
  e-mail that appears to be from a legitimate and
  well-known company to try to trick the user into
  sending confidential information.
• The practice of disguising an e-mail or a web
  site so that it appears to belong to a well-known
  company such as yahoo, Google or others is called
  spoofing.

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Phishing

• The e-mail typically lists a URL that will direct
  victims to a spoofed web site that gives every
  appearance of being the legitimate web site of a
  familiar company.
• Many users recognize phishing attempts by
  noticing obvious spelling or grammatical errors.
• Current phishing attacks are estimated to have a
  3 success rate.

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419 Scams

• The 419 scam, or advance fee fraud, is a very
  popular cyber crime committed using e-mail.
• This scam gets its name from a section of the
  Nigerian penal code, because the vast majority of
  this type of crime originates in that country.
• E.g. have to pay money to attend a seminar or has
  money and needs help etc.

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DOS attacks

• Sending a lot of traffic to deny the network from
  functioning.
• DDOS (distributed denial of service), a Trojan
  horse is used to download a small program onto an
  unsuspecting internet users computer. The
  program transforms the computer into a zombie
  that is used to send messages to the target of
  coordinated DDOS attack.

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Brute force attacks
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Cyber crime countermeasures

• Internet explore security settings
• Encryption and authentication
• Symmetric and asymmetric encryption
• Digital certificates
• Digital signatures
• Secure sockets layer (SSL) protocol
• Biometric authentication

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Threats to privacy

• Spam
• Adware/spyware
• Cookies
• Inappropriate content

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Privacy countermeasures

• Spam blocking methods
• Spyware/adware avoidance
• Cooking blocking
• Parental control software