What is a network?
- Two or more computers connected for communication and transmission of data
What are the 5 main components for a computer network?
- Sever
- Clients
- NIC (network interface card)
- Protocols
- Communication media (e.g. wired or wireless though the internet of bluetooth)
What do servers do?
- Provide services to the other clients connected to the network (must be a powerful computer for bigger networks)
What is the job of a NIC?
- A NIC allows transmission of data, recieving data and communication over a network
What are protocols?
- These are rules to be able to communicate within networks
> Essentially the language computers use to communicate
What are 4 advantages and disadvantages of computer networks?
Advantages:
- Allows shared software in the main system
- Can easily share files
- Easy to back up data and store all on a local server
- Able to share common external resources e.g. printers
Disadvantages:
- The cost of the server and communication media can be expensive
- A larger network will require special training and a lot of knowledge on the topic
- If the server shits down, access to all files stored on that server become unaccessible
- A virus can easily spread though the whole computer network
What are LAN’s?
- Local Area Networks
- Usually hosted by a single unit
- Covers one geographical site/ building
What are WAN’s?
- Wide Area Network
- Covers huge geographical area (the internet)
- Slower transmission speeds than LAN due to distance
What are PAN’s?
- Computer network organised around one individual’s device
- Requires connection of two or more devices
- Use bluetooth, which is slow asf
Describe how bus topology works? Describe 2 advantages and disadvantages of this topology
- uses a backbone to connect the server to every other device in the topology
Advantages:
- Cheaper than other topologies (due to small amount of cabling needed)
- Does not depends solely on a single device (such as star does)
Disadvantages:
- Performance severly hit with too many connections
- Whole system shuts down if central cable fails
Describe how a star tolopgy works? Describe 3 advantages and disadvantages
- Has a central hub (which is connected to a router)
- All over devices connect to this hub, without connecting to eachother
Advantages:
- Better performance
- Data is not sent to every device on the topolgy
- Can work even when a node is severed
Disadvantages:
- If central hub crashes, whole system crashes
- More expensive than bus
- Performance and number of devices that can be connected depends on the servtal hub’s capacity
How do wireless networks transmit data? What are the benefits of wireless networks? What are the risks and disadvantages?
- Transmit data though radio waves and retrieved by devices though antenna, which the waves get converted from analogue to digital (0,1’s)
Benefits:
- No cables
- More freedom in terms of where data can be accessed (e.g. westfields wifi)
- Relativley cheap
- Can easily be expanded
Risks and disadvantages:
- Can be easily intercepted (because it literally radio waves)
- If the router has no security, files can be easily accessed by an outsider
- You have to be in range of the wifi connection (the further away you are the worse teh connection)
- Usually slower speeds compare to wired connections
What are 3 things that effect wireless connection?
- Distance
- Amount of people connected
- Signal interefence
What is a WLAN?
- Wireless Local Area Network
- So LAN but wirelesss
