Zusammenfassung der Ressource
1.4 Wired and Wireless Networks
- CLIENT SERVER
- receives and processes requests from clients
- what user does on computer is sent to central computer
- workers can update central databases
- server stores users account details
- ADV.
- easier security management
- easier backups of shared data
- easier to install software
updates to all devices
- DISADV.
- expensive to set up+maintain
- requires IT specialists to maintain
- server=sing. point of failure
- PEER-PEER
- all computers have equal status
- ADV
- cheaper to set up
- relatively easy to maintain
- allow individual devices to share
files between each other
- no dependance on server
- no need for network manager
- DISADV.
- less secure network
- users manage own backups
- difficult to
maintain well
ordered store
of files
- WAN
- telecommunication company
provides infrastructure
- larger geographical area
- LAN
- own infrastructure
- telecommunication owned
by organization
- Local Area Network
- small geo area
- HARDWARE
- NIC
- connects device to wireless/wired network
- uses protocols
- WAP
- allows wireless-enabled devices
to access net. without cables
- bandwidth=lower
- security=weak
- SWITCH
- sends data between com on LAN
- only send traffic to correct device
- unrecognisable= broadcast packet to all connections
- ROUTER
- sends data between networks on WAN
- cannot access WAN without it
- uses IP address
- DNS SERVER
- Domain Name System
- has list of all domain
names and IP addresses
- hosting
- CLOUD
COMPUTING
- load files from any
location and any time
- data automatically
backed up
- large capacity
- share files easily
- VIRTUAL
NETWORK
- part of a LAN/WAN
- configured so that certain
devices can see each other
- SCALABILITY
- users can be connected to diff. switches
but appear to be in same network
- bandwidth used more efficiently
- SECURITY
- users cant access other devi.
- COST
- don't need to change
infrastructure as busi.
changes
- VPN
- Virtual Private Network
- send data securely over a WAN
- PACKETS
- Packet number
- Sender and
receivers IP address
- internet protocol
- set of rules that govern
how devices communicate
- CABLES
- FIBRE OPTIC
- doesn't suffer from electrical interference
- transmit data through light
- covers longer distances
- higher bandwidth
- COPPER
- electric conductor
- cheap +flexible
- e.g. STP, UTP
- disadvantages
- shorter lifespan
- corrosion
- affects quality of bandwidth
- WHAT AFFECTS PERFORMANCE OF NETWORK?
- cable(transmission media)
- bandwidth - amount of data
that can be transmitted in a
certain amount of time
- no.of users
- distance - weaker signal if far
- latency - caused by
bottlenecks in infrastructure