1.5 - Network Topologies V.2.

1.5 - Network Topologies V.2.

1. Mesh Network

   • A network where all devices are connected directly to each other

2. Star Network

   • A Network where all devices are connected to a server by an individual wire.

3. Ethernet and WIFI

   • Benefits of ethernet
     • Stable connection
     • Less chance of being hacked
     • More secure
     • Faster traffic speed
     • Usually has a good signal quality
   • Benefits of WiFi
     • Cheap set up cost
     • User can move around.
   • Flaws of WiFi
     • Loses connection through walls or objects
     • More likely to be hacked than ethernet

4. Encryption

   • Is a method of scrambling data with a key code that makes no logical sense

5. What is a network?

   • It is a number of devices linked together to share resources, such as hardware, software and data

6. IP address

   • Unique string of numbers separated by full stops which identifies every device using Internet Protocol to communicate over a network.
   • Is possible to change

7. MAC addresses

   • Media Access Control
     • Uniquely identify the specific device being used by identifying the network adapter.
   • Come with the device when bought, embedded in during manufature. You can't change it.
   • Built into a Network Interface Card (NIC)

8. Protocols

   • A set of rules/conventions that control the communication between devices on a network
   • Key Protocols:
     • TCP/IP
       • Transmission Control Protocol/Internet Protocol
         • A set of rules that control the connection of a device to the internet
     • HTTP
       • Hyper Text Transfer Protocol
         • Rules used when transferring data
     • HTTPS
       • Hyper Text Transfer Protocol Secure
         • A more secure HTTP
     • FTP
       • File Transfer Protocol
         • Rules that have to be followed when transfering files
     • POP
       • Post Office Protocol
         • Rules followed to retrieve e-mails from a mail server
     • IMAP
       • Image Message Access Protocol
         • POP over a TCP/IP connection
     • SMTP
       • Simple Mail Transfer Protocol
         • The internet standard for e-mail

9. Packet Switching

   • All data sent through devices is sent in packets.
     • It is broken into packets and given a header which contains the IP adress of the network that it is being sent to.
       • The packet contains the network address source, network address destination, packet number/sequence, error detection codes and the payload
       • The header also contains a number out of the total packet-making it easier to reassemble
       • Sometimes packets get lost so the computer has to request that the packet is sent again, if it never arrives, then the router deletes it
   • How does packet switching work?
     • Data is split into individual packets.
       • Each packet is then given a packet number
         • Router reads the packet and sends it
           • Receiving device will read the packet number and reassemble the data in the correct order.

10. Layers

    • As a packet is prepared, the data travels through layers where protocols manage it, adding or removing extra information as required