Data Representation
- Describe and exemplify the use of binary to represent positive and negative integers using two’s complement, including the range of numbers that can be represented using a fixed number of bits.
- Conversion of two’s complement numbers from binary to denary and vice versa.
- Describe and exemplify floating-point representation of positive and negative real numbers, using the terms mantissa and exponent.
- Describe the relationship between the number of bits assigned to the mantissa/exponent, and the range and precision of floating-point numbers.
- Describe Unicode used to represent characters and its advantage over extended ASCII code (8-bit) in terms of numbers of characters.
- Describe the relative advantages and disadvantages of bit-mapped graphics versus vector graphics.
Computer structure
- Describe the concept of the fetch-execute cycle.
- Describe the factors affecting computer system performance:
- number of processors (cores)
- width of data bus
- cache memory
- clock speed
Environmental Impact
- Describe the environmental impact of intelligent systems:
- heating systems
- traffic control
- car management systems
Security Risks and Precautions
- Describe and identify the implications for individuals and businesses of
the Computer Misuse Act 1990:- unauthorised access to computer material
- unauthorised access with intent to commit a further offence
- unauthorised modification of programs or data on a computer
- Describe and identify the security risks of:
- tracking cookies
- DOS (Denial of Service) attacks:
- symptoms
- slow performance, inability to access-
- effects
- disruption to users and businesses
- costs
- lost revenue, labour in rectifying fault
- type of fault
- bandwidth consumption, resource starvation, Domain
- symptoms
- Name Service (DNS)
- reasons
- financial, political, personal
- reasons
- Describe how encryption is used to secure transmission of data:
- use of public and private keys
- digital certificates
- digital signatures
