Download IEB SAGS IT Theory Notes- Full Syllabus and more Exams Network Theory in PDF only on Docsity!
Local Area Network - correct answer -Networking capabilites of a group of nodes near each other(Buildings, homes etc)
Node - correct answer -User devices which connect to a network Networking devices - correct answer -Devices used to create a network
- NIC- Switch
- Repeater
- Bridge- Router
Switch - correct answer -Central networking device used to connect nodes in a star topology allowingthem to communicate and adding an extra layer of control
Repeater - correct answer -Networking device used to join network segments over long distances Advantage: Boosts signal strengths over long distancesDisadvantage: Does not mitigate network congestion
Server - correct answer -More powerful computer in a network used to manage access and use ofnetwork resources
NIC - correct answer -Physical interface between network and the computer which allows the networkcables to connect to a computer, this also has the MAC Address of each device built in.
Bridge - correct answer -Networking device which connects network segments together strengtheningsignals which pass through it, looks at MAC address and only forwards packets which are on a different network segment
- Has a bridging table to track devices on each network segment
- Wireless bridges used to connect network segments in different buildings. Router - correct answer -Sophisticated device used to connect different networks that use the sameprotocols
- Boosts signals and uses nodes IP Addresses to determine best path for data packets to travel through
- Routing table stores info about all networks which router is connected to
- Assigns IP Address (DHCP)
- Allows devices to connect to the internet- Allows cross network communication
Bound Media - correct answer -Wired connection where signal is confined to connection medium Twisted Pair Cable - correct answer -Two insulated strands of copper wire twisted around each other- Twisting prevents electrical interferences
- Grouped together in a protective outer covering to form a cable Types: STP (Shielded twisted pair)- UTP (Unshielded twisted pair)
Weaknesses of copper cable - correct answer -- Attenuation: Loss of signal strength over a distance (+/-100m)
- Crosstalk: Signals from one line interface with signals from another line (Adjacent wires signal'sinterfere with each other) NB: STP less susceptible than UTP due to shielding
Bluetooth - correct answer -Wireless technology standard for sending data over short distances usingshort wavelength radio transmissions
- Handles voice and data NFC - correct answer -Provides wireless connection between two devices within close proximityallowing for two way connection between both devices
Radio Waves - correct answer -Electromagnetic wave known for their use in communicationtechnologies and data transfer carried over wireless network Point to point communication - correct answer -Transmission technology which directly connects twonodes in a network
Broadcast Communication - correct answer -Communication channel shared by all devices in a network Topology - correct answer -Physical Setup of a network describing how the network devices and nodesare connect
Star Topology - correct answer -A topology in which all nodes are connected to a central device switch(Switch) where a cable is plugged into the node's NIC and the other end to the switch
Adv:- Extendable
- Removing does not break system Disadv:- Lots of cables
- If switch fails system fails
Bus topology - correct answer -All nodes are connected by a single cable which has a terminator at eachend
Adv:- Less cables
- Now switch = Lower price
- Easier to add node Disadv:
- Faults harder to trace- Cable fault collapses network
Ring topology - correct answer -Nodes are interconnected in a closed loop drawn like a ring, each nodeboosts the signal acting as a repeater
Adv:
- Can easily extend to create larger ring
- Little degradation as each node is a repeater- Each node has the opportunity to transmit
Disadv:- Slower than star topology
- One node may cause a system failure Ethernet - correct answer -Technology that connects nodes in a network and allows them tocommunicate through a common protocol.
- Describes how devices can transmit.
Hotspot - correct answer -Site that offers internet access over a wireless LAN with the use of a router orwireless access point connected to a link to an ISP typically using Wi-Fi technology.
Wireless Bridge - correct answer -Component which connects network segments without using a cablesimilarly to a normal bridge and provides a data path between two network segments.
Wi-Fi Router - correct answer -Networking device which allows multiple computers to join the samenetwork and provides access to the internet
- Can function as a switch and as an internet router and access point. Wi-Fi vs Ethernet - correct answer -- WiFi is faster how ever ethernet is more consistent, faster andmore reliable.
TCP/IP - correct answer -Protocol which has rules that govern how devices communicate over theinternet ensuring that communication is transferred to the correct device.
- Defines how data is formatted, addressed, transmitted etc..
- Internet browser uses this to connect to internet and email browser uses it to send an receive emails IP Address - correct answer -Numerical label assigned to each device in a network so that the device cancommunicate on the internet.
IPV4 - correct answer -Uses 32 binary bits to create a single unique address on the network- 4 groups of base 10 numbers seperated by dots ranging upto 255
IPV6 - correct answer -Uses 128 binary bits to create a single unique address on the network
- 8 groups of hexadecimal numbers seperated by colons
- If a group has all zeros it can be discarded i.e: 2001:0001:2024:0000:0000:2910:A7D2:9F2E -> 2001:0001:2024:::2910:A7D2:9F2E Mac Address - correct answer -Hardware identification number used to identify each device on anetwork which cannot be changed.
This number is built onto each devices NIC
- Each device must have one to be part of a LAN 48 bit serial number with six groups of hexadecimal numbers seperated by colons -> 00:0D:81:B1:E3:8E Protocols - correct answer -Rules which govern how data is transmitted between nodes and overnetworks
ARP - correct answer -Each device in a network has a unique mac address which must be linked to an IPAddress stored in the ARP table in the RAM of the NIC.
- ARP Table has a list of Mac addresses and IP Address so that it can see which device sent the data
- Can be accessed in command prompt by typing "arp -a" DNS - correct answer -Maintains a directory of domain names and translates them into IP Addresses so that when a web address is entered the ISP translated the DNS associated with the domain name intoa machine-friendly IP Address.
Satellite Radio Waves - correct answer -Use of satellite technology to provide voice and video calling,internet, television and radio channels.
- Spans very long distances other communication media cannot handle. Components:
- Transponder- Antenna
- Communication Paylod
- Switching systems- Command
- Control system Features of satellite - correct answer -- Usually used in geostationary (Stays fixed above a single pointon the equator)
- Available globally on both land and sea
- Handles long distance with ease
- Highly reliable- More expensive with higher data costs
- More secure than other communication forms and even used by military- Provide weather information.
- Helpful during times of disaster.
- High amount of data can transmitted. Microwave - correct answer -Communications system that uses a beam of radio waves in themicrowave frequency range to transmit video, audio, or data between locations.
Cellular Technologies - correct answer -Mobile phone networks consist of many signal areas called cells
- Cells overlap with each other to create coverage for a large area
- Within each cell there is a base station or mobile phone tower which sends and receives the mobiletransmissions.
3G - correct answer -G means generation
- Improved data transfer by supporting many larger data formats such as standard HTML pages, videosand music.
LTE - correct answer -Improved speeds 4G - correct answer -Faster connection speeds and mobile hotspots
- Allows users to view digital media on their mobile devices 5G - correct answer -Smarter, faster and more efficient than 4G- Mobile data speeds that far outstrip the fastest home broadband network currently available
- Low latency: Can download and upload files much faster than before Wi-Fi calling - correct answer -Allows you to make a call over the internet with no additional cost, usefulwhen unable to connect to a cell network
ADSL - correct answer -Uses telephone lines to transmit data along copper cables from your nearesttelephone exchange to your home or office
Bandwidth Comparisons - correct answer -Internet speed: Rate at which information travels from theweb to your device, download speed is normally higher than upload speed as internet activity is focused on downloading data. Copper cables are often affected by bottlenecks: more traffic = slower download speed
FTP - correct answer -Protocol used to transfer files across the internet, used for display the file on yourbrowser
WebDAV - correct answer -Extension of HTTP protocol used for communication between clientbrowsers and web servers
Internet - correct answer -A global network which is a connection of networks Web 1.0 - correct answer -Collection of HTML Webpages, snail mail and discussions Web 2.0 - correct answer -Dynamic websites, faster internet, easier sharing, using multiple devices etc Web 3.0 - correct answer -Personalisation, custimation for each use, unique internet profile Web 4.0 - correct answer -Adapts to mobile surroundings known as symbiotic web Scripting - correct answer -Set of instructions which are sent from a client or server Client side scripting - correct answer -Servers sends the client an instruction set along with data andclients machine builds the webpage and does the processing
Server side scripting - correct answer -Instructions are send to the server by a user to which the serverthen responds and executes then returns a result based on the users instructions
Application - correct answer -Application in which your machine processes the data but does not own itnor does it own the software
- Speed based on components Web Based - correct answer -Application in which the server processes- Speed depends on bandwidth
- Easily accessible Cookies - correct answer -Small piece of data sent from a website stored in a user's browser while theybrowse the website
Streaming - correct answer -Portion of a file is loaded into memory from a server as opposed to beingsaved where the file is never owned
Downloading - correct answer -Copy saved to secondary storage where it is first loaded into memorywhen downloading where buffering occurs, when it is then used a portion of the file is loaded into memory from secondary storage as opposed to from a server Video on Demand - correct answer -Platform where a user can select a video in which they would like towatch from a menu of available videos
VoIP - correct answer -System which uses the internet as a service for telephonic communication Mobile Website - correct answer -Condensed version of a desktop version of a website which is easierto run and uses less resources
- Can be run on any mobile device with a browser and internet connection Mobile application - correct answer -Applications which are downloaded and installed on mobiledevices and accesses data and content from the internet.
Native mobile app - correct answer -Application written using a native language (built specifically forthe device's OS) and platform specific tool Developer has access to device capabitilies Hybrid mobile app - correct answer -Blend of native (built specifically for an OS) and web solutions usingcross platform web technology (HTML, CSS and Java)
Podcast - correct answer -Series of on-demand audio files which focus on a specific theme or topic. Vodcast - correct answer -Series of on demand video files which focus on a certain theme or topic. Compression - correct answer -Encoding data so that it can be transferred using fewer bits than it hadoriginally contained
- NB: A compressed file is decompressed before being opened Lossy Compression - correct answer -Reduces number of bits in a file by removing unnecessary contentthus lowering the quality
JPEG for imagesMP3 For Audio
Lossless - correct answer -No information is lost and the restored file size is the same as the original filesize
Sample Rate - correct answer -Number of audio samples captured every second Bit Rate - correct answer -Number of bits per second of audio which are processed in kbps Bit depth - correct answer -Number of bits available for each clip (allocated to each sample) in kbps MP3 - correct answer -Compressed version of WAV or AIFF- Removes sounds we cant hear
Quality vs. Bandwidth and Speed - correct answer -Amount of compression required for files dependson use of file
ZIP Files are commonly used for compression File is unzipped and decompressed using utility
