Connectivity

Connectivity

1. Home network

   • Most homes network use it mainly to allow users to share an internet connection.
   • Local area network
     • To create a home network you need to set up a local area network or LAN.
       • This connects all the compures in the home of the home network, so you can share reasons.
     • Beneifits of a home network:
       • Sharing the internet connection
       • Sharing files, including backup files.
       • Sharing peripherals, like printers and scanners
       • Internet telephone services.
     • You would need a network inerface card (NIC) to connect the computer to the home network, unless you are using a Wi-Fi dongles.
   • Routers
     • Connecting to the internet from a home network, you need a router.
     • This router would connect all of the computers to the modem by giving them an internal IP address, so it 'knows' where to send the data.
     • Most internet service providers will give you a modem and router combined.

2. Network security

   • Wirless networks are less secure then cable ones. If you do not scure your wirless network then anyone within range can access it.
   • The importance of security
     • When you connect to your own wirless network, you might see the other that are within range.
     • As you can see theirs, then they can see your, and if it is not secure, then they could be able to use your internet at your cost.
     • Even if you trust your neighbours, there are website that publish the location of unsecured 'hotspots'. So people can use it with out paying of it.
   • Ways of securing wirless networks.
     • Changing the default password on therouter.
     • Setting up a form of encryption
     • Reducing transmitter power
     • Setting up the Media Access Control (MAC) address filtering
     • Hiding the router by stopping the router broadcasting its Service set identifier (SSID).
     • Truning it off when not in use.

3. Bandwidth and latency

   • Using a network connection involes transferring bits (1s and 0s) between two devices.
   • Network performace is how well the network can tranfer the bits.
   • Bandwidth and latency are two measurements to describe the perormance of network connection
   • Bandwidth
     • Bandwidth is the number of bits that can go through the network connection in 1 second.
     • Its is measured in bits per seconds (bps)
     • 1Kbps means 1 thousand bits can be transmitted every second
     • 1Mbps means 1 million bits can be transmitted every second
   • Latency
     • is the time in milliseconds between a bit leaving one device and arriving at the other.
     • It is measured in milliseconds (ms)
     • low latency= low ms
       • High latency= high ms
   • User Experience
     • Streaming videos from YouTube, you need a high bandwidth network connection.
       • Otherwise the video willkeep pausing as your computer waits for more bits to arrive.
     • To get a quick seach from Google you need low latency network connection.
       • This is because information is travelling in both directions so it need to arrive quickly.

4. WiFi and mobile broadband

   • The most common ways of connecting to the internet on the move are WiFi hotspots and moblie broadband which relies on the 3G network at persent.
   • WiFi
     • WiFi devices need to be within range of a wireless access point or 'hotspot'.
     • Good range- works up to 60 metres from the hotspot.
     • Speeds of up to 54 Mbps
     • Quite widely available.
     • Hackers sometimes set up fake WiFi hotspots putting users' details at risk
     • Cannot use if not in range of an access point
   • Mobile broadband
     • Far greater coverage then WiFi
     • More secure then WiFi- data encryted.
     • Have to pay for mobile broadband, including roaming charges if you are abroad.
     • Downloads limited.
     • Lower bandwidth then WiFi

5. Peer-to-peer network

   • It is when digital devices communicate wirelessly with each other directly without the need for transmitter between them.
   • In the past
     • Devices communicated with eachother throught a transmitter: a wireless access point when uesing WiFi and mobile phone mast when using mobile broadband.
   • WiFi direct
     • New technology that allows devices to connect directly using WiFi without the need for a wireless access point.
   • Bluetooth
     • Allows devices to communicate automatically when within range of each other.
     • Can have uo to 8 different devices connect at the same time.
     • It's low power.

6. VoIP

   • Voice over internet protocol
   • Set of rules for sending audio messages over the internet.

7. SMYP

   • Simple mail transfer protocol

8. HTTP

   • Hypertext transfer protocol

9. Keeping people out of your place

   • Fit blinds so people cannot see in
   • Issue swipe cards (storeds personal info in the card stripe)
   • Require all people entering the buliding to authenticate their identity
   • Install colsed circuit television (CCTV) cameras inside/outside.
   • Install burglar alarm ans fit monitors in every room.
   • Fit doors with security keypads and keep them locked
   • Use biometrics, for exmple fingerprints or iris scanner.