1. Unit 1 Fundamentals of IT
LO5 – Understand ethical and operational issues and threats to computer systems
5.4 – Physical Security
5.5 – Digital Security

2. Learning Objectives
Know about physical and digital security methods and their characteristics.
Including:
Physical Security
Locks, biometrics, RFID, tokens, privacy screens, shredding
Digital Security
Anti-virus, firewalls, anti-spyware, usernames/passwords, permissions, encryption
This will lead to an understanding of why different security methods are needed in different contexts.

3. Physical Security

4. Locks
Locks or keypads are useful on the physical protection of computer systems.
By having locks or keypads on rooms or storage facilities can prevent access.
This can prevent physical damage to computer system and equipment

5. Biometrics
These are devices that help determine people’s identify using specific readers.
These can be fingerprints, eyes or facial recognition and voice.
The reader will be able to match the person’s features to a database
Matching the person to the records will then allow access.
Biometrics is used in a number of applications as a security device, i.e. some of the latest mobile phones use fingerprint matching before they can be operated; some pharmaceutical companies use face recognition or retina scans to allow entry to secure areas.
Fingerprint scans compare images of fingerprints against recorded fingerprints in a database. The system compares ridges and valleys that are fairly unique.
Retina scans (eyes) use infrared light to scan the unique pattern of blood vessels in the retina. It means people have to be still for seconds while scans take place but is very secure as it is difficult to duplicate blood vessel patterns

6. Biometric Technique Comparisons
Comparative accuracy
Comparative cost
Devices needed
Social Acceptability
What can interfere with the process
Fingerprint scans
High accuracy
Medium
Scanner
Damaged fingers (e.g. cuts)
Signature recognition
An optical pen
High
Signatures can change with time
Retina Scans
high accuracy
Digital Camera
Low
Irritation of the eye
Iris Recognition
Wearing of glasses
Face Recognition
Medium-Low accuracy
Facial hair or glasses
Voice Recognition
Medium accuracy
Microphone
Background noise or having a cold

7. Biometric Advantages/Disadvantages
Biometric Technique
Advantages
Disadvantages
Fingerprint scans
One of the most developed biometric techniques
Very high accuracy
Very easy to use
Relatively small storage requirements for the biometric data created
For some people it is very intrusive since it is still related to criminal activity
It can make mistakes if the skin is damaged (cuts)
Signature recognition
Non-intrusive
Requires very little time to verify (about 5 secs)
Relatively low cost technology
If individuals do not sign their names in a consistent manner there may be signature recognition problems
High error rate (1 in 50)
Retina Scans
No known way to replicate a person’s retina
It is very intrusive
It can be relatively slow to verify retina scans with stored scans
Very expensive to install and set up
Iris Recognition
Verification time is generally less than 5 secs
Very intrusive
Uses a lot of memory for the data to be stored
Face Recognition
Non-intrusive method
Relatively inexpensive technology
It is affected by changes in lighting, hair, age and use of glasses
Voice Recognition
Verification takes less than 5 secs
A person’s voice can be recorded easily and used for unauthorized access
Low Accuracy
An illness, e.g. a cold, can change the pitch of a voice, making absolute voice identification problematic.

8. RFID RFID stands for Radio Frequency Identification.
It uses radio wave or electromagnetic waves to identify and track individuals, animals and items of importance
Read more on RFID here: identification

9. Tokens These a small hardware devices that allow people access
Could be a key fob or smart card
In the IT setting they can be used to allow people access to a network.
Another example is customers in bank being sent tokens to access online banking services.
More information here:

10. Privacy Screens
These can be used to prevent content being seen or read by anyone not sitting in front of the screen
This is useful to stop others glancing across from different angles to see the content.

11. Shredding
This is the process of cutting up documents, cards or optical discs into sufficiently small pieces so that it is impossible to reconstruct them.
This is the most effect methods of protecting physical data no longer required from falling into the wrong hands.

12. Digital Security

13. Anti-Virus / Anti-Spyware
These are programs that protect the computer system form other maliciously downloaded programs.
It means that they identifies the software that is harmful and quarantines or destroys the virus or spyware.
works/

14. Firewalls
This is either software or hardware and sits between the user’s computer and an external network (i.e. the internet) and filters information coming in and out of the user’s computer. The following list are tasks carried out by the firewall:
To examine the ‘traffic’ between a user’s computer (or internal network) and a public network (i.e. the Internet)
Checks whether incoming or outgoing data meets a given criteria.
If the data fails the criteria, the firewall will block the traffic and give the user (or network manager) a warning that there may be a security issue.
The firewall can be used to log all incoming and outgoing traffic to allow later interrogation by the user
Criteria can be set up so that the firewall prevents access to certain undesirable IP addresses.
Firewalls can help prevent hackers or viruses from entering or gaining access to the users network. This can be done by blocking IP addresses but hackers can still access the network if they use allowed computers.
If the user is warned if some software on their system is trying to access an external data source (i.e. an automated software upgrade); the user is given the option of allowing or denying the request.

15. Firewalls
When filtering traffic through a network, there are 3 filtering mechanisms used:
Packet Filtering – Firewall analyses the “packets of information” (i.e data) and blocks any unwanted or offensive packets.
Proxy – Firewall takes on the role of a recipient and sends the data received to the node that had requested the information
Inspection – Firewall marks key features of any outgoing requests for information and checks for the same key features of the data coming into the computer system/network. It decides whether it is relevant

16. Firewalls

17. Username/Passwords Provides protection on 2 levels
Username is linked to a group or groups. These groups allow access or give permission for the user to access particular software (eg. Financial systems or HR)
Passwords can allow the user access to the information system and software (eg. Internet access, word processor, spreadsheet, )
Further passwords can be set for access to sensitive data.

18. Usernames/Passwords
Passwords should be a combination of letters and number that are difficult to guess. Stronger passwords normally contain special characters, combinations of upper and lower case, numbers.
Many systems require the password to be types twice for verification and normally include a limit of password attempts.
Double Authentication is now becoming more popular where people use different methods of accessing their account using passwords or keys

19. Permissions
These are rules that determine who can access an object and what they can do with it.
Examples could be shared access to a file on the network.
Think about permissions within school – who can access student workgroups, staff workgroups.
Think about people having the ability to edit files and those who only have read only access.

20. Encryption
This is when data is encoded so that it cannot be understood by people who are not authorised to see it.
Access can only be done with a secret code known as a key.
Used primarily to protect data in case it has been hacked or accessed illegally. While encryption will not prevent hacking, it makes the data meaningless unless the recipient has the necessary decryption tools.
Encryption uses a secret key that has the capability of altering the characters in a message. If this key is applied to a message, its content is changed, which then makes it unreadable unless the recipient also has the same secret key. When the key is applied to the encrypted message, it can be read.
The key used to encrypt (encode) the message is called the encryption key; the key used to decrypt (decipher) the message is knows as the decryption key. When a message undergoes encryption it becomes cypher script, the original message is known as plain text. Figure 8.9 shows how these link together.

21. Encryption

22. Task Create these 2 tables on Physical and Digital Security.
Make notes on these different security methods and give advantages and disadvantages where possible
Physical Security
Measure
Explanation
How this increases security
locks
biometrics
RFID
Tokens (e.g. key fob)
privacy screens
shredding
Digital Security
Measure
Explanation
How this increases security
anti-virus
firewalls
anti-spyware
username/passwords
permissions
encryption