Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

a - cs > jan mocks dk > Flashcards

jan mocks dk Flashcards

1
Q

network layer

A

encapsulates IP packets into frames
maps IP to MAC
specifies requirements of hardware to be used
delivers packets to network

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

defining pointer data type

A

TYPE Tmonth = ^STRING

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

random file

A

records stored in any available position
location found using a hashing algorithm on the key field

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

TCP/IP +

A

+ break processes down into manageable self contained modules
+ easier to develop + make software/ hardware compatible

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

application layer

A
  • what user sees
  • contains programs that exchange data
  • send files to transport
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

HTTP

A
  • user types URL
  • HTTP requests from application to transport
  • transport creates packet which is sent to destination ports
  • DNS server looks up IP
  • sends transport acknowledgement
  • communication established between web server and browser
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

circuit switchinge eg

A

PSTN

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

packet switching eg

A

VoIP

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

massively parallel computers

A
  • large number of processors connected
  • simultaneously performing a set of coordinated computations
  • network infrastructure
  • communicate by sending messages
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

features of SISD and SIMD vs MISD and MIMD

A
  • if SI - sequential processing - can use pipelining
  • if MI - each processor is independent
  • all except SISD - can be used as parallel computers
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

Describe how the layers of the TCP/IP protocol stack interact with each other

A
  • Each layer can only accept input from the next higher layer or the next lower layer
  • There is an interface between the adjacent layers which is the only interaction between layers
  • Data is added to the headers as the frames/packets pass through the layers
  • User interaction takes place at the highest/Application layer of the stack through protocols associated with that layer
    of the stack
  • Direct access to hardware takes place at the lowest/Link layer of the stack.
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

set

A
  • user-defined composite data type
  • … which includes a list of unordered elements
  • Set theory operations, such as intersection and union, can be applied to these elements
  • A set data type includes the type of data/data type it uses as part of its definition
  • All the elements are of the same data type.
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

PSUEDOCODE of set

A

TYPE SymbolSet = SET OF CHAR
DEFINE Operators (‘+’, ‘–’, ‘*’, ‘/’, ‘^’) : SymbolSet

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

segmentation

A
  • space is broken into varying sized blocks called segments
  • Each segment has a name and size.
  • During execution segments from logical / virtual memory are loaded into physical memory.
  • The address is specified by the user
  • Segments are numbered
  • … and this number is used as an index in the segment map table.
  • A segment map table maps logical / virtual addresses to physical addresses
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

disk thrashing

A
  • when virtual memory is being used.
  • As the main memory fills up, more and more pages need to be swapped in and out of virtual memory.
  • This swapping leads to a very high rate of hard disk access / excessive disk head movements.
  • takes a long time
  • Eventually, more time is spent swapping pages than processing data thrash point, which can cause the program to
    freeze or not run.
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

record

A
  • A user-defined composite data type
  • It uses other data types in its definition to form a single new data type
  • The data types referenced may be primitive data types from a programming language or they may be other userdefined data types.
  • Includes a fixed number of items.
17
Q

Outline how the kernel of an OS acts as an interrupt handler.

A
  • the kernel receives a signal when an interrupt is generated
  • the kernel checks the priority and reviews the status/priority of the current interrupts
  • system enters kernel mode if the type of interrupt is of higher priority than the current process
  • saves the state of the interrupted process on the kernel stack
  • the kernel restores the process state e.g. contents of registers once the interrupt is serviced
18
Q

object vs class

A
  • An object is an instance of a class
  • No memory is allocated when a class is defined, but objects are allocated memory space whenever they are created
  • A class cannot be manipulated as it is not available in the memory, but objects can be manipulated
  • A class is defined but an object is declared
  • A class can use inheritance. An object cannot.
19
Q

Explain the role of a digital certificate in creating a digital signature.

A
  • The digital certificate provides the public key
  • … that can be used to validate the private key associated with the organisation/website/digital signature
20
Q

need for protocols

A
  • Protocols provide a standard set of rules that enables successful data transfer between devices.
  • Allows communication between devices on different platforms.
  • Makes communications independent of software and hardware.
21
Q

recursion

A
  • process using a function that is defined in terms of itslef and calls itself
  • defined usintg a base case - terminates and not recursive
  • and general xase - recursively defined solution
22
Q

benefit of a user interface

A
  • hids complexity of hardware
    eg using a GUI click and icon rather than write code
23
Q

running > ready state

A
  • fixed time slice is up
    and there is a process with higher priority in queue
  • or interrupt arrives
24
Q

causes of exception

A

user errors
programming errors
hardware failure
runtime error

25
Q

stack vs queue

A

FIFO vs FILO
both vary in size
queue has 2 accessible ends - stack has one

26
Q

virtual memory

A

secondary staorage is used as main memory
temporarily
data swapped between RAM and VM when needed
CPU appears to access more that avaialable RAM memory

27
Q

O logn

A

time taken goes up linearly as number of items rises exponentially
worst case scenario
big O notation describes time complexity of an algorithm

28
Q

2 stacks used for a queue

A
  • second stack reverses order or first
  • stack one is queue - stack 2 is empty
  • to add an element pop all elements from stack one and push to stack 2
  • push on new element
  • pop from stack 2 and push back to stack 1
29
Q

why private

A

To ensure that attributes can only be accessed by the class’s own methods
To enforce encapsulation // ensure they are hidden

30
Q

why normalise

A
  • To store the maximum range of numbers in the minimum number of bytes / bits
  • Normalisation minimises the number of leading zeros/ones represented
  • Maximising the number of significant bits
  • … enables very large / small numbers to be stored with accuracy.
  • Avoids the possibility of numbers having multiple representations.
31
Q

reasons for including exception handling routines

A

To trap (some) runtime errors
To prevent a program halting unexpectedly
To produce meaningful error messages for these errors
eg divide by zero // end of file // file not found

32
Q

SSL and TLS

A
  • The SSL and TLS protocols provide communications security over the internet / network
  • … they provide encryption
  • They enable two parties to identify and authenticate each other
  • … and communicate with confidentiality and integrity.
33
Q

imperitive programming lang

A
  • Imperative languages use variables * … which are changed using (assignment) statements
  • … they rely on a method of repetition / iteration.
  • The statements provide a sequence of commands for the computer to perform * … in the order written / given
  • … each line of code changes something in the program run.
34
Q

declarative lang

A
  • Instructs a program on what needs to be done instead of how to do it
  • … using facts and rules
  • … using queries to satisfy goals.
  • Can be logical or functional
  • Logical - states a program as a set of logical relations
  • Functional – constructed by applying functions to arguments / uses a mathematical style
35
Q

recursion using stack

A
  • A stack is a LIFO data structure
  • Each recursive call is pushed onto the stack
  • …. and is then popped as the function ends
  • Enables backtracking/unwinding … to maintain the required order
36
Q

Explain how a compiler makes use of a stack when translating recursive programming code.

A

MP1 The compiler must produce object code to One mark per mark point (Max 3) MP2 …push return addresses / values of local variables onto a stack MP3 …with each recursive call // … to set up winding MP4 …pop return addresses / values of local variables off the stack … MP5 …after the base case is reached // … to implement unwinding.

a - cs (26 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2025 Bold Learning Solutions. Terms and Conditions