CA7 Flashcards
State:
Purpose of Batch OSs
Collects programs and data together in a batch before processing
State:
3 functions/features of a batch OS
3 of:
* Processes batches of data at regular intervals
* No user interaction required
* Batch processing carried out when least demand for processing power
* Can be set up to run at specific times
* Batches processed on a first-come-first-served basis
State:
Purpose of Multi-tasking/Time-sharing OSs
Enables the use of a single computing resource for multiple uses at the same time
State:
3 functions/features of a multi-tasking/time-sharing OSs
3 of:
* Involves processor carrying out multiple tasks at a time
* Programs being used are eitehr waiting, runnable or running
* OS schedules the processes to be exectured by the CPU
* As the OS facilitates multi-tasking, several aplications can be stored in the RAM at same time complex to setup
State:
Purpose of Real-time operating systems (RTOS)
Swtiches between tasks rapidly giving the impression that programs are being executed at the same time, Aids the management of different hardware resources and hosts the applications that run
State:
3 purposes of real-time operating systems (RTOS)
3 of:
* Typically used for embedded applications
* Data is processed as soon as it is received by the processor
* It is high performance - fast response time and based on user requirements
* Priority scheduling
* Higher security and reliability standards
* It will always produce the same output if the same input is used - known as determinism
State:
Purpose of network operating systems (NOS)
Runs on a server and provides capability to manage users, groups and security applications and data and other networking functions. Facilitates sharefile and printer access across multiple users
State:
3 functions/features of network operating systems (NOS)
3 of:
* Centralised servers are stable
* Security of the network is managed by the server
* Facilitates remote access to the servers from different locations and types of systems
* Upgrades using new technologies and hardware are easily integrated into the system
* Purchase and running costs are high
* There is a dependency on a central location
* Regular updates and maintenance are required
State:
Purpose of mobile OSs
Software platform to run mobile devices. Responsible for determining its functions and features of the device. Determines which third-party apps can run on the device
State:
3 types of mobile OSs
- Android OS - Google’s open and free software stack that includes an OS, middleware and key applications
- iPhone OS/Apple IOS - only available on devices manufactured by apple -derived from Mac OS
- Windows Mobile - Microsoft OS used in smartphones and mobile devices with or without touchscreens - based on windows CE 5.2 kernel
State:
Software that is used to help manage, control and maintain the computer system and associated resources
Utility Software
State:
2 examples of utility software, that are not built-in to OSs
2 of:
* Anti-virus
* Anti-malware
* Registry cleaners
Define:
Application software
Specific programs that are installed onto a computer system or made available via the cloud, for end-users to perform a range of tasks
State:
2 examples of application software
2 of:
* Graphics software
* CAD software
* Office suite; Microsoft 365
* Browser software; Google chrome, Firefox
Define:
Code Development Tools
Tools used by programmers when developing software, enabling them to create, maintain and debug the software they are developing
Explain:
Integrated Development Environments (IDEs)
Access tools within one central interface, include, at minimum, a source code editor, compiler and debugger and sometimes other tools; class and object browsers and class heirarchy diagrams
State:
3 examples of tools used by developers (other than an IDE)
3 of:
* Source code editor
* Compiler
* Debugger
* Assembler
* Linker
Fill The Blank:
Not all ……………….. which make up a digital system are suitable for all …………………….., their environments or the industry sector that they are in
Components, Businesses
Fill The Blank:
When using a component (software, hardware, …………………) it is important to consider the …………………. and …………………… of the component to make sure it is ………………….. and will produce the benefits that the business requires.
Peripherals, Benefits, Drawbacks, Appropriate/Required
Define:
Feature of a component (software, hardware, peripheral)
Something that a digital system, hardware/software component or peripheral has associated with its functionality
Define:
Benefit of a component (software, hardware, peripheral)
Outcome/result from using the digital system, component or peripheral
Define:
Drawback of a component (software, hardware, peripheral)
Something which can have a negative effect on or disadvantage a business
Explain:
What RAID means and what it is
- RAID - Redundant array of independent disks
- Combining of multiple disk drives into a single unit (array)
Fill The Blank:
Because disks in RAID work in …………….., RAIDs are more ………….. and ……………. and reduce …….. loss and improve overall performance
Unison, Reliable, Faster, Data
Fill The Blank:
The increase in ………… and ……………… from using RAID depend on the ……… used
Speed, Reliability, Type
Explain:
RAID 1
- Also called disk mirroring
- Two identical sets of disks and used for redundancy
- If one drive fails, the business can still operate and the broken drive easily replaced with all data copied across from functioning drtive
State:
1 advantage and 1 disadvantage of RAID 1
Advantage:
* Increase in read performance due to data being able to be read from either of the two functioning drives
Disadvantage:
* Slightly higher rate latency as the data must be written to both drives in the array
Define:
Redundant/Redundancy
Where a system is still able to function regardless of issues that may occur
Define:
Read Performance
The time taken to open a file from storage
Define:
Rate latency
The amount of time (delay) it takes to send information from one point to the next
Explain:
RAID 5
- Contains at least 3 drives (possibly more) with blocks of data being striped across the multiple drives
- Parity bits written across each drive after each sequence of saved data
- Parity checksum is storedo n one drive and used to calculate the value of the parity bits to check whether any data is missing and replace it
- Usually has its own hardware controller
State:
1 advantage and 1 disadvantage of RAID 5
Advantage:
* Even more increased performance to RAID 1 because of data striping because data is spread across the drives and can all be read at once
Disadvantage:
* Can only withstand one disk failure and means other data backups should be implemented
Explain:
RAID 10
- Combination of disk mirroring and disk striping
- Requires at least 4 drives and a disk controller
- Four disks divided into 2 sets of 2 where each set is RAID 1 for two different sets of data
State:
2 advantages and 2 disadvantages of RAID 10
Advantages:
* Data redundancy due to there being a mirrored image of the data
* Increased read/write performance because of data striping
* Rebuild time reduced in the event of a disk failure as long as a mirror image is still available
Disadvantages:
* Does not have parity checking
* If a total failure of one sub-array occurs, the entire system can crash
Define:
Data striping
The technique used to store consecutive segments of data (eg: a file) on different physical storage devices
Define:
Parity
A technique that checks whether any data has been lost or overwritten when it is moved from one storage place to another or transmitted between computers on a system
Explain:
What NAS means and what it is
- NAS - Network Attached Storage
- Storage device that is connected to a network and acts as a central point for the storage, management and access of files
Fill The Blank:
As the ……… is connected directly to the network, it can only be accessed by …………………. networked devices or users
NAS, Authorised
Fill The Blank:
NAS is configured with data transfer ……………. (DRPs) such as Network File System (NFS) allowing the …………………….. of data between devices
Protocols, Transmission
State:
2 advantages of using NAS
- Easy to add additional storage - just have to add additional disk drives
- Data recovery and backup is easier - but should never be only backup option
Explain:
What does SAN mean and what it is
- SAN - Storage Area Network
- Network of interconnected storage devices accessible by computers and servers
- Purpose is to store, manage and protect data
Fill The Blank:
SAN uses ………….. storage where data is broken down into …………… and stored seperately with each ………… given a unique identifier and a software program …………………….. the requested …………….
Block, Blocks, Block, Reassembles, Block
Fill The Blank:
In SAN, once a request is made, the software identifies the blocks based on their unique identifier and …………………. them into one ……… that is then accessible for the user
Reassembled, File
Fill The Blank:
Block storage system means data can be accessed more ………….. than a standard file-storage system and can be accessed using different types of …………………. …………………
Quickly, Operating Systems
Fill The Blank:
A ………. network is usually connected using ……….-………. cabling which is faster than other forms of cabling and uses a protocol known as fibre channel providing better ……………………
SAN, Fibre-Optic, Performance
Fill The Blank:
SANs are ………………… in relation to the technology required and it is also complex to set up, ……………… and …………………….. meaning that there is the additional cost for a skilled ………………….. manager to monitor and maintain the SAN - they are however more easily ……………. by adding hard disks and switches
Expensive, Configure, Maintain, Network, Scalable
Explain:
2 advantages of connecting devices to form a network
2 of:
* Reliability - a central servber means data is still available if a device fails
* Accessibility on a global scale - If network is a WAN, then resources like data, files, info are accessible to the user of a connected device regardless of location
* Manageability - Server-based networks, individual software applications do not need to be installed on every computer connected to the network, the software is installed and can be upgraded/updated centrally and then be readibly accessible to all connected devices
* Security - Controlled centrally to mitigate risks against security breaches
Explain:
2 disadvantages of connecting devices to form a network
2 of:
* Servers - a server-based network will be reliant on servers for files or mail, meaning its important that networks have powerful computers used as servers which makes it easier to set up and maintain the network
* Implementation costs - Initial costs are high with hardware (servers, switches etc.)
* Maintainability - Complex configurations and installations, these tasks can only be completed by experienced network specialists who can demand high wages for their skills and knowledge
* Security - Security risks especially with large networks with many users that could introduce viruses etc when accessign and sharing resources and files
State:
4 advantages of wireless networks
4 of:
* Quick to deploy
* Supports increased mobility
* Lower cost of setup
* Aids the use of BYOD (bring your own device)
* simpler maintenance
State:
4 disadvantages of wireless networks
- Shared medium - can become congested
- Connectivity is not guaranteed
- Security for businesses can be a concern
- Throughput drops further you are from the access point
Fill The Blank:
WiFi …… networks can be used to connect devices in an area with no …………. ………………
Mesh, Physical Cabling
State:
The three common speeds found in the UK of WiFi networks
2.4GHz, 5GHz, 6GHz
Fill The Blank:
A higher WiFi speed means more ……….. at a higher ………….
Devices, Speed
Fill The Blank:
A wireless network is easily ………………. without needing major re-configuration. A wireless network can also use ………………… and web-content ………………..
Scalable, Application, Filtering
State:
5 advantages of wired networks
5 of:
* Supports high bandwidth to endpoints
* Dedicated connection if using switch
* Full duplex operation
* Supports large distances
* Stable and not prone to interference
* Greater security
* High level of user control
State:
5 disadvantages of wired networks
5 of:
* Expensive to install
* Can take a long time to install
* Expensive to upgrade
* Lack of mobility
* Inconvenient
* Higher maintanence costs
Fill The Blank:
Because a wired network uses physical …….. it is reliant on ………………. cabling at a location to be used
Cables, Infrastructure
Fill The Blank:
A wired network will use either …………. or …….. optic cabling to connect devices to the network
Copper, Fibre
Define:
Full Duplex
Send and receive at the same time
Fill The Blank:
Fibre optics may be used over copper because they are harder to …….
Sniff
Fill The Blank:
A wired network will be much higher …………….. than a wireless alternative
Bandwidth
Define:
LAN
Local Area Network - Connection of groups of computers and low voltage devices across short distances
Define:
WLAN
Wireless Local Area Network - Same as a LAN, but without cables connecting the hosts and servers (often using WiFi)
Define:
WAN
Wide Area Network - A series of LANs that have been joined together, often not owned by one person
Define:
WWAN
Wireless Wide Area Network - Use mobile phone signals which are provided by mobile phone services
Define:
PAN
Personal Area Networks- Very small networks connecting devices within one building and used by an individual or small business
Define:
WPAN
Wireless Personal Area Network - Wireless version of a PAN, using bluetooth or WiFi and have limited distance accessibility
Define:
Bandwidth
Measurement of how much data can be transfered between one point to another on a network, over a set period of time
Define:
Speed of a network
Rate at which data can be sent over a network
Fill The Blank:
It is important that the ………………. of a network is able to handle the required …………….. of all devices connected to the network so that the overall ………… is acceptable for all users
Bandwidth, Bandwidth, Speed
Define:
Symmetrical bandwidth
Same amount of data can be transmitted in both directions
Define:
Asymmetrical bandwidth
The upload bandwidth is smaller than the download capacity
Fill The Blank:
When installing a network it is important to calculate the amount of ……………… required
Bandwidth
State:
2 steps into calculating the required bandwidth for a network
1) Find out how much network bandwidth is available
2) Find out average usage required by each application
(both expressed in bytes per second - Bps)
Define:
Latency
Measure of time taken to transmit data from one point to another over a network
State:
What unit latency is measure in
Milliseconds (ms)
Describe:
How distance impacts latency
The further away a user is from the destination of a packet, the longer it will take to be sent
Fill The Blank:
DSL, cable and fibre optic have a lower latency than …………. because this, although it travels at the speed of light has to travel further than the alternatives and is therefore slower
Satellite
Fill The Blank:
A ………. takes time to process data and therefore latency occurs
Router
Define:
Propogation delay
Length of time it takes the data packets to travel from the device to the server
Fill The Blank:
If a ………… location takes a long time to process data it can become a ………………. in a network
Storage, Bottleneck
Fill The Blank:
An efficient network will have high ……………. and low …………
Bandwidth, Latency
Define:
Bottleneck
Limitation of data flow by a network resources
State:
What name is given to the computers on a network
Client
Explain:
Briefly, a client-server network
Client-server Network Model
Server with computers connected to it
Fill The Blank:
The server is used to provide …………….. and ………………………. to the client computers but is …………………. protected from being accessed at each client
Client-server Network Model
Services, Resources, Password
State:
2 common uses of client-server networks
Client-server Network Model
2 of:
* Web service
* Games hosting
* Private networks
State:
1 advantage of a client-server network
Client-server Network Model
Centrally controlled - control of all connected devices is easier
State:
2 disadvantages of a client-server network
Client-server Network Model
- If the server fails, the whole network is not functional
- A lot of clients on the network will cause network traffic congestion which can slow the system down
Explain:
Thin client
Thin client Network Model
Runs by accessing resources on a central server
Fill The Blank:
A thin client does not have local ………………..
Thin client Network Model
Storage
State:
2 advantages of thin clients
Thin client Network Model
- Because resources are accessed from central server, operating costs are lower
- Easier to do maintenance, set security requirements or upgrades because all data is stored on a central server and changes only need changing on a central server
- Simple to increase size of network (scalability) by adding new thin clients to network
Explain:
Briefly, peer-to-peer network model
Peer-to-peer Network Model
No central server, where peers (clients) act as clients and servers to all other peers on the network
State:
What a P2P network allows users to share
Peer-to-peer Network Model
- Folders/Files
- Peripherals
Fill The Blank:
Each device on the network provides ……………….. to the network and ……………….. resources the network provides
Peer-to-peer Network Model
Resources, Consumes
True or False:
A P2P network has worse performance than a client-server network
Peer-to-peer Network Model
False - They have better performance
State:
2 advantages of P2P networks over client-peer networks
Peer-to-peer Network Model
- Cost of a peer to peer network is lower
- Easy scalability in comparison
Explain:
Differences between a logical and physical topology
Physical: Physical structure and layout of devices on a network; devices, cabels, switches etc.
Logical: Way data passes from one device to another through the network or how it acts on the network media regardless of physical connections
Explain:
Star network topology
- Each device is connected to a central device using a point-to-point link.
- Central hub receives signals from a node and transmits (repeats) the signal to all other connects nodes.
- The hub manages and controls all network functions
State:
2 advantages of a star network topology
2 of:
* Easy to install, wire and reconfigure
* No disruption to the network when connecting or removing nodes
* Easy to troubleshoot. This is because all data goes through a central point
* Faulty equipment such as network cards, media and nodes can be easily isolated
State:
2 disadvantages of a star network topology
2 of:
* If the hub fails, the network fails
* It requires more cabling than many other topologies
* It can be expensive (mainly due to the cost of the hub)
Explain:
Mesh network topology
- Often used in WANs
- Every devices has a point-to-point contact with every other device in a network - fully connected mesh topology
Because the fully connected approach is impractical, a hybrid approach is sometimes used when critical devices are interconnected (partial mesh topology)
State:
2 advantages of a mesh network topology
2 of:
* No traffic problems because of the dedicated links
* It is more robust than other topologies; if there is a failure in one of the links, it does not impact the whole system
* Data travels down a dedicated line and is more secure
* Fault detection is easier as there are point-to-point links