Connectivity

Connectivity

1. Home Networks

   • To create a home network you need to set up a local area network (LAN). This connects all the computers in the house so that resources can be shared.
     • Benefits of a home network:
       • Sharing the Internet Connection
       • Sharing files including backing up files
       • Sharing peripherals e.g. printers
   • You need a network interface card (NIC) to connect the computers to the network unless you are using WI-FI dongles
   • Routers
     • Connecting to the internet from a home network requires a router. The router connects all of the computers to the modem by giving them an internal IP adress so it knows where to send the data.

2. Types of networks

   • Cable connection to router (using Ethernet Cables)
     • Setting up - Cables have to be run from the router to all the rooms in the house (Disadvantage)
     • Cost - Installation is expensive (Disadvantage)
     • Bandwidth - Very fast (Advantage)
     • Security - good a user would need to physically need to plug their computer into the network with a cable (Advantage)
     • Interference - should not experience any (Advantage)
     • Mobility - You have to unplug and reconnect if you want to move room (Disadvantage)
   • Wired connection to router (using radio waves or microwaves)
     • Setting up - all you need is a wireless router (Advantage)
     • Cost - cheaper: only the cost of the router(Advantage)
     • Bandwidth - slower (Disadvantage)
     • Security - poor anyone within range can use it unless it is secure with a password (Disadvantage)
     • Interference - can be affected from distance, objects and number of computers (Disadvantage)
     • Mobility - You can access the network anywhere in the house and stay connected when moving between rooms (Advantage)

3. Network Security

   • Ways of securing wireless networks
     • Changing the default admin password on the router
     • Setting up a form of encryption
     • Setting up a Media Access Control (MAC) address filtering. You can specify which addresses can connect to your wireless network
     • Hiding the router by stopping the router broadcasting its Service Set Identifier (SSID)
     • Turning of the router when it is not in use
     • Reducing transmitter power

4. Combining technologies

   • Communication technologies in different devices can work together
     • For example a mobile phone and a laptop are compatible because they both have USB ports and can communicate via Wi-Fi or Bluetooth

5. Bandwidth and Latency

   • Bandwidth: Measurement of capacity. Number of bits that can go through the network connection in 1 second. Measured in bits per second
   • Latency: Measurement of delay. The time between a bit leaving one device and arriving at the other . Measured in millieconds

6. Wi-Fi and mobile Broadbrand

   • Wi-Fi devices need to be witin range of a wireless access point or hotspot
     • Advantages: Good range from hotspot, quick speed and widely available
     • Disadvantages: Cannot use if not in range of an access point,hackers sometimes set up fake Wi-Fi hotspots putting users details at risk
   • Mobile broadband allows users to connect to the Interenet via the same network that 3G mobil phones use
     • Advantages: Greater coverage than Wi-Fi, more secure than Wi-Fi as data is encrypted
     • Disadvantages: Downloads are limited,Lower Bandwidth than Wi-Fi, have to pay for mobile broadband

7. Peer- to- peer networks

   • Wi - Fi Direct
     • Allows devices to connect directly using Wi-Fi without the need for a wireless access point
       • Advantages: Wi-Fi direct allows users to set up peer to peer networks, also allows devices to use an access point for normal Wi-Fi use
   • Bluetooth
     • Advantages: Allows devices to communicate automatically when within range,can connect up to eight devices at the same time, low power so does not interfere with other devices

8. Communication Protocols

   • VoIP
     • Voice over internet protocol is the set of rules for transmitting audio messages over the internet. The rules enable you to make free voice calls from your computer to your friends computer. An example would be Skype.
   • POP3
     • Post office protocol takes the email from the server and delivers it to the recipient's computer. If the recipient uses POP to read the email the mail server will download the email to the computer. The email is then deleted from the server and can be read offline.
   • iMAP
     • If the recipient uses Internet message access protocol the email Is read on the mail server . It can be accessed anywhere using any computer with an internet connection.
   • SMTP
     • Simple mail transfer protocol is used when email is sent from the sender's email client e.g. outlook to the sender's email server and when the email is delivered to the recipient's email
   • HTTP
     • Hyper Transfer Protocol is the protocol of the World Wide Web