Describe what is meant by a clock speed of 3.8 GHz.
State the functions of the following protocols
POP -Stands for post office protocol
SMTP- Simple Mail Transfer Protocol
FTP - Stands for the file transfer protocol
State the functions of the following protocols
POP -Stands for post office protocol
SMTP- Simple Mail Transfer Protocol
FTP - Stands for the file transfer protoc
Describe the query criteria given below
(a) Like "*kenya*"
(b) Like "*ina"
(c) Like U*
(d) Not Like U*
(e) >= "Mexico"
(f) Like "[A-D]*"
(g) "USA" Or "UK"
State THREE reasons why binary is used in developing digital electronic systems (3marks)
Differentiate between action query and select query
An action query is used to modify, add, or delete data in a database whereas a select query is used to retrieve data from a database based on specified criteria but does not make any changes to the data.
State two reasons for the increased use of computers in offices (2 marks)
A company has decided to use a computer for stock control. Describe the process of systems development from the time the decision was made to proceed with computerisation until final testing.
specify output requirements
design documents/screen displays
data for input/storage
form design
storage devices
file structures/access/design
data security/back up files
systems flowchart etc.
implementation i.e. pilot/intermediate/parallel running
testing strategy
training
hardware/software
programming/algorithms
validation
user manual
technical documentation
entering data into system
Briefly describe the following
Multitasking - the capability of an operating system to enable users to run two or more programs at once on a single computer
Real time processing - data processing system in which the time interval required to process and respond to inputs is so small that the response itself is useful for controlling the physical activity of a process
Time-sharing processing - a processing mode in which the central processor serves two or more users with different processing requirements (tasks)
On-line processing - is that type of processing where the result of data processing transaction is available immediately
List Three file organisation methods in a computer
Name three types of cables used in data communication
Twisted pair cables
Coaxial cables
Fibre optic cables
Explain how the techniques of
(i) verification,
(ii) validation
are used to ensure that the stored data is as accurate as possible.
Dual input of data
Rules are given to the processor
Drop-down list/radio buttons
Differentiate between modulation and demodulation as used in data communication
Modulation refers to the process of converting a digital signal to analog signal at the transmission end while demodulation is to converting analog signal to digital signal at the receiving end
Give one example of wireless technology
method of transmission e.g
device e.g.
Compare the use of a compiler with the use of an interpreter to translate code
Both translate source code written in high level programming languages into machine code.
Compiler: Produces a single executable file that is portable between machines
Interpreter: Source code needs a special environment to run
Compiler: Needs to be compiled for a particular architecture
Interpreter: Can run on any architecture that has the translator/interpreter
Complier: Entire source code file is translated at once
Interpreter: Code is translated line by line
Compiler: Provides error report at the end of the compilation
Interpreter: Errors more obvious in the sequence
Compiler: The program source code is not available (so helps protect IP)
Interpreter: Source code is available
Compiler: Only has to be translated once (affecting the speed of execution)
Interpreter: Has to be translated each time, therefore (affecting the speed of execution)
Compiler: Requires two files to be maintained (one for execution and for editing purposes)
Interpreter: Requires only one file to be maintained
Explain the difference between
(i) serial and parallel,
(ii) simplex and duplex
modes of data transmission.
What is an Operating System?
Give any three advantages of computer networks
Give two other uses of hexadecimal in computer science.
Ochieng manages a network for an organisation.
(a) Two computers are assigned the same IP address.
Explain why Ochieng must change the IP address of one of the computers.
(b) Identify the network topology that requires a server.
Ochieng manages a network for an organisation.
(a) Two computers are assigned the same IP address.
Explain why Ochieng must change the IP address of one of the computers.
(b) Identify the network topology that requires a server.