Networks Flashcards
What is a computer system?
Two or more computers , that are CONNECTED together that are able to exchange data with each other. Allowing software and hardware to be shared.
What are the advantages of networks?
🟢communication eg: emails & text messages
🟢file sharing , eg: stored centrally and worked upon centrally
🟢hardware sharing , eg printers , making it more cost effective
🟢user account allow you to log in from any device
🟢installing software centrally , takes less time
What are some disadvantages of networks?
🟣expensive to set up as a lot of hardware is required. eg: NIC cards, switched , cables
🟣vulnerable to hacking and malware which can spread to networked computers
🟣hard to maintain and install , may require employing a specialist
Describe a PAN
Personal area network:
- very short range(few meters)
- cantered around 1 user
A network that is spread over a very small area used to connect personal devices
🟡don’t require additional hardware, can used them on the move
🟡often wireless technology eg: Bluetooth
Describe a LAN
Local area network
🟡small geographical area located on a single site
🟡wired or wireless
🟡owned an maintained by the organisation
Describe a WAN
Wide area network
🟡A combination of LANs in different geographical locations
🟡expensive as they need to hire infrastructure
🟡under collected or distributed ownership
What is a WLAN?
A wireless local area network
What is a wireless network?
A network that connect computers to a network through electromagnetic ☢️ radiation
What is a wired network?
Makes use of physical wire to connect computers to the network
Advantages wireless 🟢networks:
🟢Wireless are cheaper to set up.
🟢Wireless also requires less information and installation is automatic.
🟢wireless can add people more easily
Advantages of wired networks🔴
🔴wired have a larger transmission speed, higher bandwidth, more reliable
🔴wired are more secured. As physical connection is needed to intercept data
🔴wired have no interference from other Wireless networks or physical obstructions like walls
What is a NIC?
Network interface card, a piece of hardware inside a device that allows it to be connected to devices
What is a WAP?
Wireless access point
Needed in wireless networks
Basically a switch needed to connect devices wirelessly
What are switches?
Used to connect devices within a LAN to form a network
Device can access the switch simultaneously
What are routers?
Transmit data between different networks
Used to connect to the internet
Compare fibre optic cables and copper cables
Fibre: transmits dat as light.
More expensive but higher bandwidth
No interference and very large distance
Copper :
cheaper but have lower bandwidth
Describe a star topology
All devices are connected to a central switch or server, controlling the network. Can be wired or wireless
What is a node?
A device connected to a network
Star network pros and cons
✅if a device fails the network is unaffected
✅fewer data collisions as all devices can transmit data at the same time
✅easier to add devices
✅packets only sent to intended devices
❌expensive as it requires a switch and other hardware
❌problem with switch then the whole network is affected
Describe a bus network
Use a single ‘backbone ‘ cable to connect all devices.
Two terminator at the end to stop data reflections (interference)
Pros and cons of Bus networks
✅if one device fails the network remains unaffected
✅cheap to set up and maintain
✅not dependant on a switch
❌frequent data collisions slowing the network down
❌unsuitable for large networks as too many data collisions
❌network fails if the backbone cable is broken
Define network protocols
A set of rules that determine how devices communicate the transmission of data across a network
Describe Ethernet
🔌A family of protocols
🔌 manages data transfer for wired LANs
Describe HTTP
Hyper text transfer protocol
Used by web browsers to access websites / communicate with web servers .
