Communications technology Flashcards
(119 cards)
1
Q
Fundamental network models
A
TCP/IP and OSI.
2
Q
Open system interconnection (OSI)
A
“Please do not throw sausage pizza away”
-Application
-Presentation
-Session
-Transport
-Network
-Data link
-Physical
3
Q
Application (OSI model)
A
Top layer of the model, that directly interacts with data from the user. Software application (web applications and client emails) rely on this layer to communicate, User application (word processing packages) are not included in this function.
Application layer is responsible for managing protocols, such as HTTP and Simple mail transfer protocol (SMTP) that allow meaningful data to be presented to user
4
Q
Presentation (OSI model)
A
Prepare data for use in application layer, such as translation, encryption and compression of data, Makes sure data is transmitted in a format that is understood by the receiving device.
Data will be encrypted if communication over a secure connection and also will decrypt data thats received. To increase speed of transmission data will be compressed.
5
Q
Session (OSI model)
A
Responsible for opening and closing communication links between devices. Ensures session is open for long enough to allow all data to be transmitted, and close immediately. Once transmission is complete.
6
Q
Transport (OSI model)
A
Responsible for breaking down the data from session layer into segments, then segments are given to network layer. Also responsible for reassembling the segments at the receiving device, flow control and error checking. Ensures all data has been received, otherwise requests a retransmission
7
Q
Network (OSI model)
A
Breaks down segments from transport layer into smaller units (packets). Responsible for reassembling packets after transmission, and routing. Router is a key component in network layer.
8
Q
Data link (OSI model)
A
Similar role to network layer, rather than transmitting data from layer to layer, it transmits from node to node within a network. Coverts packets into frames. Switch is key component in this layer.
9
Q
Physical (OSI model)
A
Involves physical equipment used to transmit the data, such as cables. Data is broken down into bits and transmitted as binary. Is responsible for reassembling the bits into frames, after transmission.
10
Q
Packet:
A
A unit of data in data transmission
11
Q
Router:
A
A network component that uses a computer IP address to send data packets to a destination outside the current network
12
Q
Switch:
A
A network component that uses a computers MAC address to send the data packets to a destination within a network
13
Q
TCP/IP Protocol layers:
A
TCP/IP model is more condensed than the OSI model, which only has 4 layers, compared to OSI, which has 7 layers.
-Application
-Transport
-Network
-Link
14
Q
Application Layer (TCP/IP):
A
Condenses application, presentation and session layer from OSI model. Uses several protocols to provide standardised exchange of data (HTTP, SMTP, Post office protocol (POP), file transfer protocol (FTP).
15
Q
Transport Layer (TCP/IP):
A
Comparable to transport layer in OSI model, Responsible for maintaining end-to-end communications between devices. TCP and UDP are the main protocols used in this level.
16
Q
Network Layer (TCP/IP):
A
Comparable to network layer in OSI model. Breaks down data into packets and transmits it network to network. IP and internet control message protocol(ICMP) are the main protocols used in this level.
17
Q
Link Layer (TCP/IP):
A
AKA physical layer< It condenses the role of data link and physical layer from OSI model. address resolution protocol (ARP) is the protocol used.
18
Q
IP (internet protocol) Address:
A
A unique address given to a device, normally by a router
19
Q
MAC (Media Access Control) Address:
A
A unique address given to a device by the manufacturer
20
Q
Structure of data packets:
A
A Data packet is sent across a network, which contains several elements.
The normal elements include: Header, Payload and Trailer.
21
Q
Header (Data packets) Includes:
A
-IP address of sender, source IP
-IP address of receiving device, Destination IP
-Sequence number of packet, so receiving device can reorder the packets to obtain original data.
-MAC address of the sender and receiver
-Any protocol that is used
22
Q
Payload (Data packets) includes:
A
-The actual data from the file that is being transmitted
23
Q
Trailer (Data packets) includes:
A
-A flag that tells a device it has reached the end of the packet
-Any error checking methods that are used
The data sent to header and trailer are designed to make sure payload data arrived at its intended destination without any errors.
24
Q
Transmitting data packets
A
-Circuit Switching: Direct path is created between the sending and receiving device, there are dedicated pathways to transmit data packets. A pathway can only be used if data transmission is completed.
-Packet switching: Data packets sent across the network can take any available path. Normally used when packets are sent over the internet, via routers.
Two methods of packet switching are Connection-oriented and connectionless. In Connection-oriented packet switching a session is created before any data is transferred. Connectionless, does not require prior set up between devices to transmit the data.
-Message switching: An intermediate method between circuit switching and packet switching. Once data packets are sent from computers to the first witch device, The device holds the data packets untill all units have arrived. data packets are sent from switch to switch, until they reach the final computer. (Strore and forward method).
25
Connection-Oriented Packet switching:
-Frame relay: Data is separated into units called, frames. Error correction is carried out by devices at end points of transmission, which speeds up transmission.
If error is detected in a frame, The frame is dropped and the endpoints will detect the dropped frames and retransmit them. Thus more suitable as error rate is low.
The two main methods of connections in frame relay is Permanent virtual circuits (PVC), connections intended to exist for long periods of time, And Switched virtual circuits (SVC), temporary connections designed to exists for a single session.
-TCP: Connection is created and maintained until application software at each endpoint has finished exchanging data. It determines how data is broken down into packets, which it sends and receives from network layer in TCP/IP model. It is responsible for providing error free data transmission and managing flow of data
26
Connectionless Packet switching:
-Ethernet: Wired connection to form a network, Makes sure data is formated and transmitted in a way that other devices on the network will understand. Used in homes or schools.
-IP: Protocol used when data is sent across the internet, responsible for delivering packets of data to the receiving device.
-UDP: Alternative protocol to TCP, sends data in datagrams, does not control the flow of data or carry out error checking, Thus is more faster than TCP
Differences of TCP and UDP: UDP sends data in units called datagrams, and TCP sends data in packets. TCP carries out error checking and manages the flow of data, thus is more secure. However UDP is more faster.
27
Message switching:
An intermediate method between circuit switching and packet switching. Once data packets are sent from computers to the first witch device, The device holds the data packets untill all units have arrived. data packets are sent from switch to switch, until they reach the final computer. (Strore and forward method).
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Network
Two or more computers or devices connected together so they can communicate and share data and resources
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Local area network (LAN)
A relatively small network that is located withing a single building or site
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Wide area network (WAN)
A relatively large network that is normally two or more LAN’s that are linked.
31
Cient-server
Contains two types of computers, client and server. Servers in client-server network is the central point of control, and provide dedicated function for the network. All other computer are called network.
-Client: A computer in a network that is not a central point of control
-Server: A computer in a network that is a point of control
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Advantages of Client-server network:
-Files can be located in a single place and backed up on regular basis, thus each user not responsible to do this.
-Security for network can be controlled from a central point, thus each user not responsible for this
-Levels of access can be applied to resources and data on the servers. Beneficial when data and resources have to be confidential.
-Updates for any software or network peripherals can be carried out from central location. Thus business not reliant on each user installing updates.
33
Disadvantages of Client-server network:
-Expensive to set up as you require expensive equipment such as servers
-Expensive to maintain, specialist knowledge is required to set up and maintain servers.
-Failure of server means functionality isnt available for all users. Ex: no user can access their files if a file server fails.
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Peer-to-peer
Network that contains Peers (A computer of equal inprotance in a peer-to-peer) in order to share data.
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Advantages of Peer-to-peer
-Relatively cheap to setup, does not require expensive servers
-Requires little technical knowledge to set up
-Users are able to share data and resources
-Often has less traffic than the alternative client-server structure.
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Disadvantages of Peer-to-peer
-If peer computer is accessed by another peer computer, it affects the performance of the computer and causes it to run slower
-The data stored on each peer computer is not centrally backed up by the network. Thus if peer loses the data, its lost for everyone, unless a copy is saved locally on their computer
-The public files shared by a peer computer may be disorganised and difficult to navigate, as no central organisation system in place.
-Each user in the network is responsible for the security of their peer computer. If users arnt vigilant and their computer gets a virus, it could be passed to other peer computers in the network.
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Virtual Private Network (VPN)
Advantages of VPN:
-Data is encrypted before it is sent across the network
-Identity of sender is kept private from the destination and any hacker who intercepts a data package.
-Maintenance is not the responsibility of user, so user does not have to worry about it
Disadvantages of VPN:
-Use of VPN is illegal or controversial in some countries, as they can be used to create anonymity in certain criminal activity
-Security of the data is reliant upon a third party and their ability to create effective software and maintenance of VPN server
-Cost is involved in purchasing a VPN, such as monthly subscription fee
38
Mobile networks
Wireless WAN that uses radio to transmit and recieve communications from portable devices, such as smartphones. Mobile networks are broken down into cells
Cell vary in size:
-Picocell: Covers an area of less than 200 meters
-Microcell: Covers area up to 2 km
-Macrocell: Covers larger reigons
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Different generations of mobile network
1G: Uses analogue signals, limited to voice and text message communication
2G: Digital transmission, improved signal quality
3G: Increased data transmission, speeds up to 2Mbps, allowing internet access, video transmission and online gaming
4G: Allow data transmission speeds up to 1 Gbps, allowing greater use of video streaming facilities
5G: Fastest and more reliable connections, average download speed 1Gbps, upto 1.5 Gbps, possibly even faster.
40
Advantages of mobile networks
-Enables communication with others and access to internet while on the move, often through smart phones
-Breaking network down into cells allows for lower power radio transmitters being used, saving on energy and costs
-Limited radio frequencies used for mobile communication, frequencies can be split among neighboring cells, and reused in more distant cells. Increasing number of communications that take place at the same time.
-Larger geographical areas can be covered than by using a single transmitter, by using several low power transmitters, cover wider area
-Use of multiple transmitters means network is more robust, failure of one base station only affects one cell, leaving other areas of the network unaffected.
41
Disadvantages of mobile networks
-Quality of reception can vary and be poor towards the edge of a cell, leading to interrupted of delayed transmissions
-The use of frequency must be carefully planned to avoid interference between cells
-Technology for 5G is limited at present and could take a while and be costly to make the full technology useable.
42
Network protocols
These protocols mainly designed to increase privacy and security of data
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Tunneling
Communication protocol, allows for secure transmission of data from one network to another. Allows private data packets to be sent through public network (encapsulation), This is when private data packets are made to look like public data packets, in order to send across public network. Tunneling is used in VPN
44
SSL
Ensures connections made between web clients (User devices, web/mail servers) are secure. Uses both public and private key to encrypt data transmitted over secure connection
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TLS
Updated version of SSL, uses updated and more secure encyrption algorithms
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Internet protocol security (IPsec)
Network protocol that is designed to encrypt and authenticate data packets that are sent across the internet. IPSec is part of tunnelling process of VPN.
47
BitTorrent
Communications protocol, often used in peer-to-peer file sharing. Allows the transfer of large files such as videos. It does this through distributing the load of downloading the file across several sources on the network. Several sources (known as hosts) are collated to create a swarm. Each host will be given pieces of the file. The BitTorrent protocol allows the user to join the swarm and download the file from the available hosts. The protocol will download the file in pieces, simultaneously, from various hosts in the swarm.
48
Internet control message protocol (ICMP)
Error reporting protocol, used to generate error messages, to transmit to the sender when network problems cause delivery problems with data packets
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Address resolution protocol (ARP)
Responsible for translation of an IP address into MAC address for a device. Necessary for use between network layer and data link layer of OSI model
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Inverse address resolution protocol (InARP)
Performs opposite role of ARP, it translated MAC address into IP address.
51
Dynamic host configuration protocol (DHCP)
Network management protocol that is used to assign IP addresses to devices on a network, manages the assignment of the addresses so that network administrators does not need to manually carry out this task
52
HTTPS
Used for transferring contents of web pages across the internet, from web server to a browser. HTTPS is secure version of of HTTP, it incorporates the use of SSL protocol.
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File transfer protocol (FTP)
Responsible for the transfer of files between a client and a server in a network.
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Simple mail transfer protocol (SMTP)
Protocol used to send emails from a computer to a mail server, between different mail servers.
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Post office protocol (POP)
Used to retrieve emails from a mail server. Upon checking mail box, the email is sent from server to user’s device. The protocol then deletes the email from the server
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Internet message access protocol (IMAP)
Used to retrieve email from a mail. The email is not deleted from the server compared to POP, it is only deleted when user chooses to delete it.
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Telnet
Allows user to connect remotely to another computer, via internet
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Secure shell (SSH)
Provides a secure way to access a computer over an unsecure network, carries out a strong authentication and encryption method for communication.
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Network interface card
A Network component required to attach a computer to a network.
It is an electronic circuit board that is attached into a devices motherboard. MAC is also provided when a device with NIC is provided by maufacturer. It is unique to NIC and contains the manufacturer serial number and ID. MAC address is used to identify the device when connected to the network. If a WNIC is used rather than wired NIC, it does not require a ethernet cable.
60
Hub
A network component that joins computers together and forwards data packets to all connected devices.
-The hub receives data from the sender and forwards it to every other device connected to the hub. Other devices connected to the hub will ignore the messages, if they are not at the intended destination, computer at intended destination will receive the data.
Passive hub: Will send data to other devices
Active hub: Will amplify and regenerate the signal used to send the data to make it stronger, allowing data to be received at the intended destination. which prevents data collision, caused by unnecessary traffic.
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Switch
Used as a Hub, connects devices together. Switch has capability to examine the data packet it receives and forward the data packet to only the intended destination. As it is aware of which device to send the data, using the MAC address source table. Which reduces the amount of traffic in a network, and possibility of data collision from occurring.
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Repeater
A network component that is used to boost a signal in data transmission.
-As signals are prone to deterioration, in order to retain the original quality of the signal as it travels around the network, a repeater is used. Used in various points in the network to boost the signal as it passes, through the repeater. It can be used to boost signal of a wired signal, wireless signal, and are capable of retransmitting both analogue and digital signal
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Wireless access points (WAP)
A network component that receives and transmits radio signals to allow (Wi-Fi) connection to a network.
-It allows a wireless device to connect to a wired network. Receives wireless data signals and uses wired network to transmit them to their destination, often via switch. Supports connection fo multiple wireless devices to the WAP. Thus connects the devices to the network by effectively creating a wireless LAN, however has a limit on how many devices can be connected.
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Bridges
A network component that connects segregated parts of a LAN.
-Used to connect parts of a LAN more effectively, it uses a MAC address to forward the data to the correct destination.
-It examines the data packets received, checking them against the mac address source table. If data packets destination is in another segmented part of the network it will send the packet “across the bridge” to that network. If data packets destination is within in the network, it will ignore the packet and allow it to continue to its destination.
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Gateways
A network component that joins different LANs together
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Router
Each device in the network is assigned an IP address Current version of IP address IPv4, 32-numerical bit addresses and IPv6, 128-numerical bit addresses , allows for many more possible combinations of IP addresses.
-Static IP address: Device will always have the same IP address
-Dynamic IP address: IP address could change for each internet session
-Router is used to connect LANs and LANs to WANs
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Differences of Router and Switch
-Switch will only forward on data packets to their destination within a single network. Although Router can be used to forward data packets outside the current LANs to other networks.
-Switch examines data packets and looks for MAC address to establish a packets destination, However router looks for the IP address of the destinations device and uses this to send it there.
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3 main types of routing protocols
Routers need to use routing protocols to specify how they communicate with each other. It helps specify the route that data travels from one device in a network to another. The three main types of routing protocols are:
-Interior gateway: Used to specify how routers communicate with each other within a network, such as LAN
-Exterior gateway: Used to specify how routers communicate with each other between different networks.
-Border gateway: Specific kind of exterior gateway protocol, manages the process of exchanging packets of data across the internet.
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Network connections physical
-Coaxial
-Twisted pair
-Fibre optic
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Coaxial
Type of copper cable that has a central wire surrounded by an insulating layer. Used to carry out radio frequency signals. Used in TV and cable TV connections as well as some internet connections.
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Advantages of Coaxial
-Low cost to manufacture and purchase
-Lower error rate because the central wire is within a faraday shield (Special shield used to block electromagnetical interference)
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Disadvantages of Coaxial
-Has the lowest level of bandwidth of the three cable types
-The way in which coaxial cable is insulated can make it difficult to install and maintain
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Twisted Pair
Type of copper cable that has two seperate insulated wired that are twisted around each other. The cables are then covered by and outer layer that acts as a jacket. Twisted pair cables transmits electric current, used for telephone communication and normally as a part of ethernet network.
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Advantages of Twisted pair
-Crosstalk (a signal transmitted from one channel to another) is minimised
-Is the lowest cost to manufacture and purchase
-Has a higher level of bandwidth than coaxial
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Disadvantages of twisted pair
-Can be susceptible to electromagnetic interference
-Has the shortest distance that a signal can be carried before it will begin to deteriorate
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Fibre optic
Type of cable made up of lots of very fine thread of glass, they use properties of light to transmit data, used in modern internet connections and in high performance networks where large amounts of data are transmitted.
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Advantages of Fibre optic:
-Has the highest level of bandwidth available of the three cables
-Can carry signals for a much longer distance without deterioration
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Disadvantages of Fibre optic
-Has the highest cost for manufacture and purchase
-Can be difficult to install due to how fragile the glass tubes can be.
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Network connections wireless
-WIFI
-Bluetooth
-Infrared
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WIFI
Each device that wants to make a wireless connection will broadcast a radio signal. A router or WAP will receive these wireless signals and process them. And will also broadcast radio signals that will be received and processed by each device when it is receiving data that has been transmitted
-Wifi transmits data at frequencies of 2.4 GHz and 5 GHz
-The current limit for wifi data transmission is approximately 450 Mbps
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Advantages of Wifi:
-The high level of frequency used means that large amounts of data can be transmitted at a time
-More recent Wifi standards are backward compatible with previous ones
-Has quite a large range of approximately 100m
-It doesn't require a line of sight, so it can work through obstacles
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Disadvantages of Wifi:
-The speed at which data can be transferred decreases as more devices connect to a wireless network
-Less secure than a wired connection
-Radio signals can be subject to interference
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Bluetooth
Uses radio signals to create a wireless connection between two devices. It uses radio frequencies if 2.45 GHz
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Advantages of Bluetooth
-It requires a low level of power consumption
-It doesn't require a line of sight, so it can work through obstacles
-Can be made more secure by requiring a pin code for connection
-There will be less interference as other wireless connections transmit on different frequencies
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Disadvantages of Bluetooth
-Has a limit of 10m for a connection
-A limit of eight devices can be connected at a time
-Has a lower level of bandwidth available than Wifi
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Infrared
Uses infrared radiation as their method of connection, two different types of infrared connection can be made. Line-of-sight mode and scatter mode
-Line-of-sight mode: There must be a direct line of sight between the sending device and the receiving device, so no obstacles in the way.
-Scatter mode: Broadcasts infrared radiations into a certain area and any device may receive it directly or through reflection of an obstacle. Sending device needs to be able to produce infrared signals and receiving device needs an infrared sensor to capture the infrared signal.
-Infrared lasers can also be used to transmit data from one device onto another in a network. Must have direct line of sight in order to connect the devices.
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Advantages of Infrared
-It is the most secure form of connection
-Low cost to manufacture and purchase
-It requires a low level of power consumption
-It doesn't get any interference from radio frequencies
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Disadvantages of Infrared
-Cannot be transmitted through obstacles
-If it uses line-of-sight mode, there must be a direct line of sight between the two devices
-It can only be used to connect two devices
-It has a short range with a limit of approximately 1m
-May be subject to interference from bright sources
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Two main protocols designed to improve level of security of a wireless network:
Wired equivalent (WEP): Designed to provide a wireless network with a compatible level of security to a wired LAN, by encrypting data transmissions sent using a wireless connection
wi-fi protected access (WPA): A standard required of devices equipped with a wireless internet connection. Designed to provide a more sophisticated encryption method than WEP
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Microwaves and Radio waves
-Microwaves and Radio waves are both types of electromagnetic radiation that can be used to transmit data.
-Microwaves have shorter wavelengths, thus used for short-distance communications
-Radio waves had longer wavelengths, thus used for long-distance communications
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Bandwidth
The range of frequencies available for a communication method which determines the transmission rate
-The More bandwidth a connection has, the more data it can transfer at a single time
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Bit rate
The rate at which bits can be transferred in data transmission
-Measure of how many bits of data are transferred in a given period of time.
-Bandwidth and Bit rate are important when streaming audio and video files
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Two different types of streaming:
-Realtime streaming: the data is streamed as soon as it is recorded by the camera.
-On demand streaming: Data is pre recorded and streamed to the users device whenever they request the recording
-When a file is streamed, it removes the need to download and store the whole file before it is viewed or listened to. Data is streamed as a series of bits to the receiving device.
-Streaming device has temporary storage, Buffer. Data is stored in buffer, as it is downloaded, before it is needed as the video is viewed, or the song is played.
-Bandwidth available will limit the quality of the sound or video file that can be streamed.
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Cloud computing Categories:
IaaS: Host provider hosts some of the network resources that are used by businesses, such as servers, they can gain access to them using internet
-PaaS: Host provider hosts platform resources that can be used to build software applications. Users can access the resources using internet
-SaaS: Host provider hosts software applications and makes them available to users using the internet.
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Advantages of Cloud computing:
-Individuals and organisations do not need to purchase additional hardware to store data and software
-do not need to host their own development platforms to develop application software
-Organisations do not need to employ technical staff to maintain the hardware used to store data and software that is provided by cloud provider.
-Do not need to worry about creating backups, automatically carried out by cloud provider
-Can access their data and software applications anywhere in the world, with internet connection
-Doesnt require software application updatation, as carried out by cloud provider
-Organisations can quickly boost performance of their network by employing more resources from the cloud.
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Disadvantages of Cloud computing:
-Reliant on a third party to keep their data secure and they have little control over the security measure put in place by cloud provider
-If resources provided by cloud provider fails, then data or software stored on that server will become unavilable
-Cloud computing resources can only be accessed using internet connection, if no internet connection, resources cannot be accessed.
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Satellite communication systems
-Communication satellites transmit radio waves from one place on earth to another. Its used for telephone calls, internet data and television broadcast, GPS.
-Their main components are solar powered battery, a transponder and various antenas.
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Uplink
When data is transmitted in the form of radio waves from a ground station to earth.
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Downlink
-When radio waves travel through atmosphere to intended satellite (chosen or nearest in orbit), antenas on the satellite will receive the radio waves.
-Transponder processes the data, and boost the signal. Antena then transmits the radio waves back to destination ground station on earth.
100
Use of satellites in GPS
-GPS uses satellites to work out a users current location
-Triangulation is carried out to find a users location, The user will be in possession of a device (Smartphone) which receives radio signals.
-Each navigation satellite contanstly beams radio waves that are sent towards earth, The device must pick up radio waves from at least 3 satellites and the GPS will be able to pinpoint their location.
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Triangulation
The process of pinpointing the location of a device, using radio signals from satellite.
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Malware
-Unknowingly a user will download malware to their computer, often disguised in a file download or a link that the user is enticed into clicking.
-The types of malware: Viruses, worms, spyware and ransomware.
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Botnet
An attack that comes from a single third party and computer, or distributed across many computers.
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How does Botnet carry out attacks
-Any users computer could be made part of a botnet, when user downloads the malware.
-Malware is downloaded onto the computer and will stay dormant until the third party wants to use the computer in an attack, Each computer infected with this attack is called bot. When user “wakes up: the malware to carry out an attack in the bot, its called botnet.
-Botnet can be used to carry out attacks such as distributed denial of service (DDoS), when bots are used to send a huge number of requests to a web server at once, causing the web server to struggle to deal with all the requests and eventually crash. Preventing legitimate users accessing
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Backdoor
A software installed, that allows a hacker to gain unauthorized access to a computer system through the backdoor, to damage or steal data.
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Brute force approach
Third parties crack into computers to damage or steal data, by trying different combinations of passwords, software could be built to carry out this function.
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Physical methods to prevent and help protect data:
-Organisations can put a barrier to entry at the opening of their office or building. They could also put a lock on a door to their office or selected area in the office
-CCTV, security guard and alarm systems. This will allow an organisation to see who is trying to gain unauthorised access.
-Security guards can stand guard and only allow authorised users to gain access to a place where data is stored (server room).
-Places of this nature could also be secured using an alarm system, will alert organisation of unauthorised access attempt.
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Data protected using Software-based methods.
-Employee may be required to provide biometric data, and checked to see if it matches data stored in a database.
-Anti-malware, anti-virus and anti-spyware software, they are designed to scan a computer system for malware, if it finds any it quarantines the malware, and allows the user to delete it. The quicker malware is found, the less damage malware can carry out.
-Firewall: Hardware based or software based, it examines incoming and outgoing traffic to a computer or a network. Can be set to recognises malicious traffic by providing it with rules and criteria to check traffic. If traffic detected does not meet criteria, it is rejected
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Impact of security threats on individuals and organisations:
-Individuals and organizations need to carefully consider the impact of security threats. As perpetrators carry out security attacks to obtain personal data or as an act of sabotage or revenge
-Individuals need to be very cautious of any of their personal data being accessed and stolen. This could lead to criminal acts such as fraud and theft of their identity. Organizations need to be very cautious of any of their stored data being accessed and stolen, and data being manipulated or destroyed.
-As it could lead to a loss of profits, or if the data is stolen because the organization’s security is breached, this could lead to a negative reputation for the organization, which may also lead to a loss of profits.
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Disaster recovery management:
-A disaster is anything that may put the operations of the organization at risk. This could be anything from a cyber-attack, power failure or a natural disaster.
-Disaster recover: A planning mechanism that allows an organisation to plan for disaster and put in place measures that will minimise the risks
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Stages involved in identifying risks that could cause disaster:
-Risk analysis
-Perpetrator analysis
-Risk testing
-Quantifying the risk
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Risk analysis
-The organization will first identify what they think could be a potential disaster, then will consider what or who could be harmed as a result.
-All parts of a company will be assessed, including its infrastructure, networks, hardware, software, and people.
-Causes of disaster in an organisation: power cut, cyber-attack, fire, flood, denial of access to data, theft of data, corruption of data and hardware failure
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Perpetrator analysis
-Often carried out as part of the risk analysis. The organization will identify who they think could be a perpetrator that could cause a disaster to occur.
-A perpetrator is someone who carries out malicious or illegal acts.
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Risk testing
-Organization will rehearse the plans and strategies that have been developed during the risk analysis.
-This will allow employees in the organization to understand exactly what they should do in the event of a disaster.
-An organization can monitor what happens during the testing stage and can amend plans to take improved actions, or to correct the behavior of employees, if they are not acting correctly.
The type of plans and strategies that could be tested are:
Restoration of data, replacement of hardware, reinstallation of software, emergency evacuation of offices, emergency protection methods for data.
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Quantifying the risk
The process of quantifying a risk involves evaluating the risk and prevention methods for the risk in terms of cost and time.
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-MTD (Maximum Tolerable Downtime)
The maximum time that each part of the organization could tolerate not having access to the essential parts of a network that they require.
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RTO (Recover Time Objective)
The estimated maximum amount of time in which an organization has in which to recover its network and resume operations.
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Methods to prevent against other disasters from occurring:
-Power surge protection devices could be used to stop a surge in power damaging hardware.
-A back-up generator could be ready for use if an organization suffers power failure.
-Back-ups of data could be stored in fire and flood proof cases so that data is not lost in a fire or flood. Back-ups could also be stored off site.
-Policies and procedures should be developed for staff to follow to prevent disaster such as fire and damage to equipment.
-Cloud computing could be used as a back-up for data and possible hardware resources.
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In the event of a disaster occurring, data and resources will need to be restored. This can often mean the:
-The restoration of data from back-ups
-The re-installation of software
-Replacement or repair of hardware.
