1
Provide the physical connection between network devices, carrying data signals quickly and reliably.
What is the name for this hardware?
Cable
A powerful computer that provides shared resources and services to other computers (clients), such as file storage, printers, applications, websites, or user authentication.
What is name for this hardware?
Server
Define cloud computing
Accessing a service/files/software on a remote server
State two characteristics of a thick-client.
Works independently without needing constant connection to a server
Can be a hardware device or software installed on a local machine
Uses the processing power of its own device to run applications
May connect to a network for updates or data sharing, but can function offline
Often used where performance, speed or offline access is important
Explain two characteristics of computers in a peer-to-peer model.
All computers are of equal status
Each computer provides access to resources and data // data is distributed
Computers can communicate and share resources
Each computer is responsible for its own security
A hardware component that allows a device to connect to a wired LAN using an Ethernet cable. It has a unique MAC address used to identify the device on the network.
What is this device?
NIC (network interface card)
Differentiate between public and private cloud.
Public cloud:
Computing services offered by 3rd party provider over the public Internet
Public is open/available to anyone with the appropriate equipment/software/credentials
Private cloud:
Computing services offered either over the Internet or a private internal network
Only available to select users not the general public
Private is a dedicated/bespoke system only accessible for/from the organisation
State two benefits of cloud computing
Can be accessed anywhere with Internet access
Do not need to install security // security might be better
Do not need to perform backups
Do not need to buy specific software/hardware
Can easily share files
Can have multiple people working on the same file
State two drawbacks of cloud computing.
You cannot access it if there is no internet access
Reliant on someone else to backup
Reliant on someone else for security // can have poorer security
Cannot access if server goes down
State all network topologies.
Bus, mesh, star, hybrid
State three benefits of networking devices
Devices, such as printers, can be shared (thus reducing costs).
Licences to run software on networks are often far cheaper than buying licences for an equivalent number of stand-alone computers.
Users can share files and data.
Access to reliable data that comes from a central source, such as a file server.
Data and files can be backed up centrally at the end of each day.
Users can communicate using email and instant messaging.
A network manager can oversee the network and, for example, apply access rights to certain files, or restrict access to external networks, such as the internet.
State three characteristics of LAN
Small geographical area (e.g., building, school, office)
Usually owned and managed by one organisation or individual
High speed (100 Mbps – 10 Gbps)
State three characteristics of WAN
Large geographical area (e.g., cities, countries, global)
Uses public or leased infrastructure from service providers
Lower speed than LAN due to distance and routing
Explain the purpose of a switch.
Connects multiple devices within a LAN and forwards data only to the intended destination device using MAC addresses.
Explain the purpose of a bridge.
Connects two LAN segments of the same type, allowing them to function as a single network.
Explain how CSMA/CD works [4 points]
Devices check if the channel is free before sending data
If the channel is busy, the device waits
If the channel is free, the device transmits the data
Since all devices share the same cable, two can send data at the same time, causing a collision
When a collision happens:
Devices detect it
A jamming signal is sent to alert other devices
Both devices stop transmitting
Each device waits for a random amount of time, then tries again
State four drawbacks of CSMA/CD
Random time increased each time so can be infinite waiting
May be a constant jamming signal so nothing ever sends
Certain nodes cannot be prioritised
High power consumption
Only suitable for short distance network // limited distance
Not scalable // more nodes means exponentially longer waiting times
BONUS
BONUS
State 2 advantages and 2 disadvantages of bus topology. Explain where it is suitable to use bus topology.
Advantages
Cheap to install—uses the least amount of cable of any layout; easy to add a new device; works well for small networks.
Disadvantages
If the shared cable breaks, the entire network fails; performance degrades as more devices are added because they share the same bandwidth; difficult to troubleshoot a fault; data collisions are common; security is weak since all traffic passes every device.
Suitability
Best for small, temporary, or low-budget networks where cost matters more than reliability, e.g. a small office or a temporary test network.
Compare how the following 6 features apply to Client-Server and Peer-to-Peer networks:
Cost
Central Server
Security & Data Control
Reliability
Ease of Setup & Administration
Suitability
*answer*
Explain how packets are transmitted between two hosts in a mesh topology
Where a direct link exists between the sender and receiver, data travels straight along that single dedicated link — no other device is involved, so there is minimal risk of collision. Where no direct link exists, the data is routed through one or more intermediate devices until it reaches its destination.
A main office for the company has four wired computers, one server, two printers, one central switch and a device providing a single point of access for the internet. The network is set up as a star topology.
Draw the topology for the main office network. Label all devices.
Describe the function of a router in a network. [3]
Receives packets from the internet or external network.
Analyzes the destination IP address of each packet and forwards them towards their destination using the routing table.
Allocates private IP addresses and finds the most efficient route to the destination
Explain how packets are transmitted between two hosts in a star topology
Sending computer transmits packets directly to switch/router/central device
Switch/router/central device checks destination address of packet and forwards directly to that device
Describe the benefits to the company of using private cloud storage instead of public cloud storage. [3]
Not reliant on a third party
...gives greater control over security/privacy
...gives greater control over backup
Storage can be tailored/scalable to company requirements