computing revision topic 3.

computing revision topic 3.

1. networks

   • network security (FAPE)
     • firewall
       • A firewall is needed to secure that nobody without access can get into your device.
       • A firewall is a system designed to help keep unauthorised access.
       • it is good to have a firewall system because it keeps unauthorised access out.
     • anti malware
       • Anti Malware software,also known as Anti-virus software,is a type of software program designed to prevent and detect programming.It protects against infections caused by many types of malware.
       • Anti-malware is needed to secure that you have a virus free device.
       • Anti-Malwear is a good thing to have because it helps to keep your device virus free.
     • passwords
       • A password is needed to make sure you have secure,non-accesable to others,websites and logins.
       • Passwords can keep people from accessing your emails,work or folders without a secure password created by you.
       • A secure password should contain at least 8 characters,and the alpha numeric mix.
     • encryption
       • Encryprition is needed to prevent unauthorised access.
       • Encryprition is the process of coverting infomation or data into a code.
       • it is good to have encryption because it is secure and can keep out unauthorised access out and can be useful.
       • Encryprition uses different keys,there's private keys distributed among the message senders.
   • LAN/WAN/WPAN
     • LAN
       • LAN HARDWARE
         • network interface card
           • contains the electronic circuitry required to communicate using a wired connection.
         • wireless network interface card
           • connects to a wireless radio-based computer network.
         • ethernet cable
           • A wired cable that allows the computer to connect to the switch or the router.
         • router
           • the router allows every device in the LAN to connect to it which alllows them to connect to the same wireless peripherals or even software,eg a printer or a sever.
         • server
           • programmed to process requests and deliver data over a LAN or the internet.
         • wireless access point
           • allows a WIFI device to connect to connect to a wired device.
         • switch
           • it can make or break the connection in an electrical circuit.
         • WIFI range extender
           • extends the WIFI over a range so that more devices can connect to the router further away.
     • WAN
     • WPAN

2. hardware

   • hertz
     • the speed measurement used for a CPU.
   • virtual memeory
     • used to allow more programs or data to be loaded when the RAM is insufficient.
   • cache
     • to store instructions or data that is frequently used,previously used or next to be used.
   • hard drive
     • stores all the programs,operating systems and files needed for the computer system to run.
   • cores
     • the number of processors in the cpu which run the fetch decode execute cycle at the same time.
     • quad core
       • 4 processors in the CPU
     • dual core
       • 2 processors in the CPU
   • clock speed
     • How many times the CPU can perform the fetch decode execute cycle per second.
   • non-volatile
     • data is not deleted from the component when there is no power connected to.
   • secondary storage
     • storage used for a computer system to save data,even when there is no power connected to it.
   • CPU
     • fetches,decodes,executes data and/or instructions.
   • magnetic storage
     • Data is stored by magnetising the surface of flat, circular plates called platters. These platters rotate at a very high speed.
   • durability
     • how robust/hard wearing the storage device is.
   • capacity
     • the amount of data a component can hold (measured in bytes).
   • solid state storage
     • Uses microchips to store data instead of magnetised disks and do not contain any moving parts.
   • optical storage
     • data is written and read with a laser.cds dvds and blue-ray are examples of this storage.
   • portability
     • how easy the storage device can be used on other devices.
   • RAM
     • stores the programs,parts of the operating system and the files currently being used.
   • computer hardware
     • all the parts inside the computer system to make it work

3. Binary (base 2)

   • binary uses 0's and 1's to show different characters.
   • all data that we need a computer to process needs to be converted into binary.
   • each digit is referred to as a bit
   • ASCII
     • used to convert binary into letters and symbols
     • American Standard Code for Information Interchange
     • character set
       • 7 bits
         • 8 bits used to have an extra 128 characters
       • algorithim
         • flow charts
           • representing an alogrithim
         • set of instructions

4. connection types.

   • bluetooth
   • GPRS
     • Uses mobile communications to connect to the internet or transfer data.
     • Examples of a bluetooth device would be bluetooth headphones or a bluetooth speaker.
   • ethernet
     • A system for connecting a number of computer systems to form a local area network.
     • Ethernet is more reliable because it can connect faster than wireless networks.The data transfer speeds are faster than the rest.
     • PS wires,XboX wires,pc wires,
     • It isn’t portable and isn't wireless
   • WIFI
     • Allows devices to connect to the Internet or communicate with one another wirelessly within a particular area.
     • An example of Wifi would be a rota,or any device needed wireless connection.
     • A disadvantage of WIFI is that you can only be a certain distance away from the source.