networks

networks

1. disadvantages of networks

   • visrus can spead more easly
   • lot of lag for lot of cummputers
   • lot of chance of collison if you have the bus lopologs

2. advantages of network

   • share/reseve fill on all of the cumputers
   • if you change a password on one it changes on all of the cumputers

3. types of network

   • WAN
     • multiple geographical locations
       • eg: wifi
   • LAN
     • local area network
       • eg: catmose and harton are coneter to a sever / lan

4. topologies

   • bus
     • advantages
       • cheap
     • disadvantages
       • hight chance of collishing
       • hight chance of catast rophie fatiere
   • star
     • advantages
       • low chance of failure
       • no collisions
     • disadvanlage
       • expensive
       • depends on a swich
   • rings
     • advantages
       • cheap
       • no collisions
     • disadvanlage
       • hight chance of falure
       • difficult to expand

5. IP addresses

   • An address is a unique identifier given to something
   • A house address (such as 15 High Street, Townsville) is an example of an address – each address is unique and used to identify that house
   • Computers on a network also need an address to identify them
   • When a computer is added to a network it is assigned an IP Address (Internet Protocol Address) The IP Address is unique value assigned to each computer on a network
   • Each IP address on a network must be unique
   • All messages that are sent over the network have both the sender and receiver’s IP addresses attached to them Each computer that receives the message checks the IP address
   • The IP Address is a 32-bit binary value This means it’s made up of 32 1s and 0s
   • While binary is perfect for a computer to use, it’s a pain for humans to use, so we convert it binary to decimal 8 bits at a time
   • Globally, there are now more devices on the Internet than the 4’228’250’625 devices it’s possible to assign a unique address to We get round this by assigning an “external” IP address to each house or business, then “internal” IP addresses to the computers in that house or business
   • Google thinks every computer in the room has the same IP address, but we know that’s not possible, as IP addresses must be unique
   • Globally, there are now more devices on the Internet than the 4’228’250’625 devices

6. internet

   • it a giant mesh of computers
     • connect by lot of routers
     • a cost is assigied to each mesh
   • inpossible to break
   • data
     • packets
       • packet are what we call chunk of data
       • sent along the lowest cost
         • cost means the connection of the network (the lower the better