Data Network Security

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Data Network Security

• By Sharmin Najreen

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Introduction

• Protecting data is one of the most important task
  in todays business world. Every computer,
  whether it is connected to the internet or not,
  has a great chance to get robbed as internet
  intruders searching constantly for valuable data,
  financial records, social security numbers, and
  credit-card information.

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And Also

• And also some internet intruders are harming
  computer users by hacking personal data for
  personal amusement.

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Protection of Data

• Todays presentation will focus
• on the security aspects of
• computerized data network.

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What is a Computer Network

• A computer network connects two or more computers
  or other computerized devices to share data, to
  manipulate data, and to communicate.
• According to Wikipedia, A computer
• network is a system for communication
• between computers.

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A Computers Components

• A computer based
• system has three
• separate components
• Hardware
• Software, and
• Data

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What is Data Network

• Data Network is a network that
• communicates with other networks about

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• Civilians personal information
• Private information about a company
• Individual pieces of a computing system
• Single Application
• Operating System
• Database Information
• Note Networks involve not only the pieces but
  also the connection among them in which data
  might get lost or might get stolen or might get
  corrupted.

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Data Networks vulnurability

• The problems are rooted in
• Networks lack of physical proximity.
• Usage of insecure, shared media
• The inability of a network to identify remote
  users.

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What Types of Data are There

• Several types of data can be at risk at any
• given network. Some examples of data are
• A companys private information,
• Computer programs,
• Login information of a companys server,
• Bank account information,
• Employee information credit card, social
  security number

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The Way Data gets destroyed

• Malicious Program
• Hacking

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Malicious Program

• Malicious codes causes undesired effects in
  programs by undesired agents.

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Types of Malicious Code

• Virus
• Trojan horse
• Logic bomb
• Time bomb
• Trapdoor
• Worm
• Rabbit

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What Will be the Topic Now?

• Now I will talk about virus as this is the most
  common way in which datas get destroyed.

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Virus Attack in Data Network

• In the simplest case, a virus inserts a copy of
  itself into the executable program file before
  the first executable instruction.
• Then all the virus instructions execute first
• After the last virus instruction, control flows
  naturally to what used to be the first program
  instruction.

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Virus Appended to Program

• This kind of
• attachment
• is simple and
• usually effective
• and most viruses
• get attached in
• this manner.

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The Brain virus

• The brain virus is one of the most earliest
  virus.
• It passes its infection by first locating itself
  in upper memory and then by executing a
• system call to reset the upper memory so that
  it can infect the memory without being disturbed.

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Prevention from Virus

• No sharing of executable code.
• Use only commercial software acquired from
  reliable, well established vendors.
• Test all software on an isolated computer.
• Open attachments only when it seems safe
• Make a recoverable system image and store it
  safely
• Make and retain backup copies of executable
  system file
• Use virus scanners and update them regularly

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Hacking

• In computer security, a hacker is a person
• able to exploit a system or gain
• unauthorized access through skill and
• tactics.

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Why Hackers are Hackers?

• Hackers steal companies or individuals personal
  information in order to
• gain profit.

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How to Secure the Network from Hackers

• We have to know all parts of a network system so
  that we can hypothesize plausible attack plans.
• Encryption is one of the most important tool for
  a networks, and, so, for its datas, security.

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How much Encryption can Protect the Data

• Although, for protection of data, encrypted
  message is not absolute assurance, but in many
  cases, the strength of encryption is adequate
  protection if we consider the likelihoods of the
  interceptors breaking the encryption and the
  timeliness of the message.

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Some Other Data Security Measures

• Firewalls
• Alarms and Alerts
• Honeypots

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Other Unwanted Intruders

• Until now, I covered about virus and about
• hackers although there are so many other ways
  in which a computer might get harmed.

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An Intruder Inside a Company

• Often there are wicked employees inside a
  company, who access sensitive data of that
  company, who should not access those information.
  
• When the programs leak information, then these
  intruders can access these private information.

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Covert Channel

• This type of data leaking is known as covert
  channels.
• A programmer might write a software, which leaks
  information, intentionally so that he can
  secretly get user's business or personal data
  for personal gain. In this case, the programmer
  is a spy.

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Covert Channels Threat

• Creates a real threat in business and in software
  users.

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Controls Against Program Threats

• Prevention is better than cure.
• Develop a secured software design policy.

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Good Software Development

• Modularity, Encapsulation, and Information Hiding
• Peer Reviews
• Hazard Analysis
• Testing

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Conclusion

• Data Network Security is a very big subject.
• As it is impossible to cover major parts of
• this subject in ten minutes, I covered few
• aspects of it and also some measures by
• which it can be possible to save data in a
• network.