Fichas
Chapter 9: Security, Privacy and Data Integrity
Fichas del conjunto (49)
- 1Data IntegrityA requirement for data to be accurate and up to date.
- 2Data PrivacyA requirement for data to be available only to authorised users.
- 3Data Protection LawA law that relates to data privacy
- 4Data Protection law 4 notes - to do with organisations- Major focus: personal - therefore private - data an individual supplies to an organisation
- Data is supplied to allow organisation to use it but only for purpose agreed by individual
- Laws oblige organisations to ensure privacy and integrity of this data
- Doesn't guarantee adherence to the laws but acts as deterrent - subject to legal proceedings. - 5Data SecurityA requirement for data to be available for use when needed, ensures that only authorized users have access to the system and data can be recovered if lost or corrupted.
(must be achieved before data integrity or privacy can be) - 62 primary aims of system security measures:- to ensure the system continues to carry out the tasks users need
- to ensure that only authorized users have access to the system - 7What are the types of threats to the security of a system? 5Individual user not taking appropriate care
Internal mismanagement
Natural disasters
Unauthorized intrusion into the system by an individual
Malicious software entering the system - 8What are the threats posed by networks and the Internet? 2Hackers and Malicious software entering system
- 9MalwareMalicious software that has the intention of causing harm to a system or its contents
- 10What are the different types of malware? 6Virus
Worm
Logic bomb
Trojan horse
Spyware
Bot - 11What is a Virus? How are categorized? give 2 examplesTries to replicate itself inside other executable code. Virus category often subdivided to software virus attaches itself to. ie boot sector viruses and macro viruses
- 12What is a Worm?Runs independently and transfers itself to other network hosts.
- 13What is a Logic bomb?Stays inactive until some condition is met
- 14What is a Trojan horse?Replaces all or part of a previously useful program
- 15What is Spyware?Collects info and transmits it to another system
- 16What is a Bot?Takes control of another computer and uses it to launch attacks
- 17Malware can be classified into terms of the activity involved. What are the 3 activities?Phishing
Pharming
Keylogger - 18What is Phishing?Sending an email or electronic message from an apparently legitimate source requesting confidential information.
- 19What is Pharming?Setting up a bogus website which appears to be a legitimate site.
Malicious code installed onto the victims hard-drive - redirects to legitimate looking site without their knowledge - 20What is Keylogger?Recording keyboard usage by the legitimate user of the system.
- 21What are the accidental damage to files? 5 and ways to counterHuman error - back up data, verifications
Physical damage eg flood/fire - waterproof/fireproof case/room
Hardware failure - use correct procedure
Power surge - surge control
Losing a storage device - 22MalpracticeNot doing your work properly
- 23System Vulnerability arising form user activity 2 not involving malwareUse of weak passwords
user not recognizing phishing or pharming attack - give away sensitive information - 24System Vulnerability arising form user activity involving malware 4Attaching a portable storage device
opening an email attachment
accessing a website
downloading a file from the internet - 25Vulnerabilities arising from with the system itself 3Operating System: overtime increase in complexity = more weak security. Regular updates
Commonly used application packages allowed macro viruses to spread (in past, now largely controlled)
Buffer overflow: Programs in C don't automatically carry out array bound checks. A program can write code to memory outside address range defined for the array, set up as a buffer. Program overwrites what stored there so when later program reads overwritten section it won't execute as should. Cleverly designed program can permit an attacker to gain unauthorized access to system and cause serious problems. - 26AuthenticationVerification of a users identity
- 27Security Measures for Protecting computer systems 7Disaster recovery
Safe system update
User authentication
Good Practice
Firewall
Digital signature: to prove sender
Anti-virus software & Intrusion detection - 28Disaster recoveryDisaster recovery contingency planning - should be based on a risk assessment. Plan for alternative system to be brought into action.
'Hot site' - full system to replace normal one. Has to be remote from original system - 29Safe System Updatesystems accessed 24/7, never closed-need to have original and replacement running in parallel for period to ensure continuity of service and allow to update
- 30User authenticationShould be user account set up on all PC's even if 1 person uses. Passwords - ASCII, also biometric methods and security tokens - can be small item of hardware for each user that confirms identity. Normally combine one with password
- 31Good PracticeDon't leave computer switched on when unattended, not writing down how access, not letting someone see how access. Attaching portable devices increases risk of transferring malware reduce use.
- 32FirewallHardware or software that monitors and controls network traffic.
primary defense, ideally will be hardware device that acts as as security gate. Nothing allowed though without being inspected. Or can be software - data must enter system but inspected immediately. Firewall can inspect system address identified in transmission of data and data itself to check. - 33Anti-virus software and intrusion detectionPrograms to check for problems ie anti-virus software - for any type of malware. Has regular scans to detect malware, remove or deactivate it. Special-purpose anti-spyware software. Intrusion detection system - take as input an audit record of system use and look for unexpected system activity. Defense must be improved continuously.
- 34Reasons for accidental loss of data 5Disk or tape gets corrupted
Disk or tape destroyed
System crashes
File is erased or overwritten by mistake
Location of the file is forgotten - 35For reasons of accidental loss of data, every system should have back up procedure to recover lost data. System administrator decides details of procedure. Procedure principles traditionally: 3- full back up is made at regular intervals, perhaps weekly
- at least 2 generations of full backup are kept in storage
- incremental backups are made on a daily basis - 36For max security What do for 24/7 systems? 2backup disks/tapes are stored away from system in fire and flood proof location. 24/7 systems: data may be changing at any time. Either 1. have backup program that freezes file store while data copied. At some time changes happening are recorded elsewhere in system. Changes can then be implemented once backup copy been stored. 2. Use disk - mirroring strategy - data simultaneously stored on 2 disk systems during normal operation - may be at remote locations - part of disaster recovery plan.
- 37Restricting access to dataSystem administrator may identify different categories of users with different needs to data allowed to see and use. Different access rights.
- 38AuthorisationDefinition of a user's access right to system components
- 39What use to protect data content?Data Encryption
- 40ValidationA check that data entered is of the correct type and format; it doesn't guarantee that data is accurate
- 41VerificationConfirmation of data received by a system
- 42Validation of data entryPrevent wrong type, format or range. Implemented by software associated with a data entry interface.
- 43What are typical validation checks? 7Presence check - entry field not empty
Format check ie dd/mm/yyyy
Length check
Range check
Limit check
Type check
Existence check ie file with filename - 44Verification of data entryGetting user to confirm data entered was intended - doesn't mean correct
- 45Give 2 examples of verification check of data entryDouble entry
Visual Check - 46Check DigitForm of verifications: requires calculation to be made with numbers entered. Finale part of calculation involves integer divided. Remainder added as extra 1 or 2 digits of series of numbers. - used for bar code or ISBN for a book
Go over - make sure can do - 47Verification during data transfer give simplest check exampleData can be corrupted during transmission - often 0 or 1 flipped. Simplest check is one bit parity check - either odd or even parity check.
Checksum - 48Even bit parity - steps how work What dis of parity check?1. At transmitting end, number of 1's in the 7-bit is counted
2. If count gives even number, parity bit set to 0
3. If odd parity bit set to 1
4. Repeated for every byte in transmission
5. At receiving end, number of 1's in 8-bit code counted
6. if count gives even number, byte accepted
7. Repeated for every byte in transmission
If no errors found, tranmission accepted (non necessarily error free - ie 2 bits flipped). Can't identify actual bit error. If error detected, re-transmission requested - 49Checksum give how work Give dis of checksumAt transmitting end a block is defined as a number of bytes. Doesn't matter what bytes represent, bits interpreted as a binary number. Sum of these binary numbers in a block is calculated and given as checksum value in transmission - repeated for each block. Received does some calculation and checks given. Error detected but position not. Detecting exact position - use parity block check
Información
- Descripción
- A Level (Unit 1: Theory Fundamentals) AS Computer Science Fichas sobre Chapter 9: Security, Privacy and Data Integrity, creado por HRYN red el 08/11/2022.
- Creado por
- HRYN red
- Visitas
- 1
- Valoración