1.3.3 Networks Flashcards
what is a network
a group of connected devices
so they can communicate + share resources
what is the benefit of shared network devices?
+ and what needs to be managed about them
- since hardware devices can be expensive, sharing them saves money
- especially as users don’t typically needed one device for themselves
must manage access to devices carefullly
describe how shared files work
- the files are placed in a shared area(accessible to many users)
- access permissions will be needed
describe what multi-user systems are
mention databases
- systems which multiple users have access to
- many are databases, which implement sophisticated access restrictions, keeping the data secure
e.g. SIMS registration and admissions
describe central backup procedures and their benefits
mention mirrored systems
- as data is backed up centrally, users don’t need to concern themselves with saving data
» this reduces the possibility of an organisation losing data - important systems can be mirrored, which involves making a duplicate system which has a copy of the live data. so if the system fails, the systems automatically switch, and the duplicate is used
define what a server is and what it does
- a program on a computer which:
- shares resources with and provides services to any authorised clients
- runs 24/7 so clients can request access to data whenever
described the centralised control of software/ updates and its benefits
- software/ software updates are distributed centrally from the server to many devices
» saving time, as there’s no need to load them onto individual devices
» allows important updates to be distributed immediately, e.g. virus protection
state three disadvantages of networks
hint: cost, cost, risk
- hardware costs for cabling and connection devices
- cost of having specialists care for the network(dep on network size)
- increase of security risks
describe the features of a LAN
there are two points
Local Area Network
- when devices in a small geographical area are connected
- infrastructure(cabling and network communication devices) are owned/ maintained by the organisation, or they employ someone to do it for them
e.g. schools, work places, homes
describe the features of a WAN
there are two points
Wide Area Network
- when 2+ networks located in a large geographical area are connected
- many lease telecommunications infrastructure owned by another company
e.g. banks connecting cash machines in a country together
what do client-server networks allow you to do?
mention access
access and share files/ emails from any authorised device
give and explain three examples of servers
file, web, print
- file server: stores and provides files
- web server: stores and provides web pages
- print server: provides print access and manages print queues
what devices are servers run on in large and small organisations?
- large org: high-power and deticated computers
» able to handle many requests simiultaneously - small org: one computer system
describe process of request between the client and server
- the client requests access to a resource held by the server
- the server processes the request
- the server sends a response to the client
e.g. browser(client) requests access to webpage, server allows, wp loads
state features of a P2P network
there are 3 points
peer to peer network
- no central servers
- every device can be configured to share resources
» device must be kept on
» the owner gives access permission to other devices wanting to access its device’s resources
- peers communicat directly with one another
give examples of resources that can be shared in a P2P network
- files
- softare
- processing power
- internet bandwidth
- hardware
define protocol
an established set of rules for transmitting data between electronic devices
give examples of protocols
HTTPS, SMTP, POP, TCP/IP
what is the difference between protocols and standards
what is the purpose of a NIC
state what it stands for
- Network Interface Controller/ Card
- to connect a device to a network(can be wired or wireless)
there are also wireless versions
describe the unique identifier on the NIC
- Media Access Control address
» used on a LAN - 48 bits long, usually represented in hexadecimal
- allocated by manufacturer, can’t be changed
why are hubs inefficient?
answer includes the purpose of a hub
- they repetitively send data to all connected devices
» including the ones which the data isn’t intended for
what is the purpose of a switch
to send data to intended destination
used in wired LANs
what is the purpose of a router
to connect 2+ networks together
can connect LANs to the internet
