Networks and their types
| English | Chinese | Pinyin |
|---|---|---|
| network | 网络 | wǎng luò |
| LAN | 局域网 | jú yù wǎng |
| WAN | 广域网 | guǎng yù wǎng |
| latency | 延迟 | yán chí |
| client-server | 客户端-服务器 | kè hù duān - fú wù qì |
| peer-to-peer | 对等网络 | duì děng wǎng luò |
| thick client | 胖客户端 | pàng kè hù duān |
| thin client | 瘦客户端 | shòu kè hù duān |
| cloud computing | 云计算 | yún jì suàn |
Why connect computers?
- A network 网络 is a set of devices connected so they can communicate and share resources.
- Networking is why we have the internet, the cloud, and shared printers at school.
- First, the benefits and the main network types.
Network route lab
Follow data from a device through network hardware and protocols.
Benefits of a network
- Share resources — one printer, file server or internet link for everyone (cheaper).
- Share data — many users open the same files.
- Central management — install software, manage users and back up once, on a server.
- Communication — email, video calls, messaging — and remote access from anywhere.
A wide-area network links many systems across a large area
Select all the genuine benefits of using a network.
Sharing resources, central backup, and communication are all benefits. Networks do not make computers slower.
LAN 局域网 vs WAN 广域网
- A LAN (local area network) covers a small area (home, office, school), is usually owned by the organisation, and is fast with low latency 延迟.
- A WAN (wide area network) covers a large area (city, country, world) using telecom infrastructure, with lower speeds and higher latency.
- The internet is the largest WAN; a WAN connects LANs together.
A network switch: each cable plugs into a port, and the switch forwards frames to the right port
Which best describes a LAN?
A LAN covers a small area (home/office/school), is usually organisation-owned, and is fast with low latency. A WAN covers a large area.
Match each networking term to what it is.
LAN vs WAN is about size; client-server vs P2P is about whether there is a central server.
Client-server 客户端-服务器 vs peer-to-peer 对等网络
- Client-server: powerful servers provide services (files, web, email); clients request them. Central and easy to manage, but the server is a single point of failure unless backed up.
- Peer-to-peer (P2P): every machine is an equal peer — each is both client and server, with no central server. Robust to one failure, but harder to secure and keep consistent.
Client-server: clients request services from a central server.
Peer-to-peer: every node is an equal peer — both client and server, with no central server.
A weakness of the client-server model is that:
Everything depends on the central server, so if it fails (and is not backed up) the service is lost. Its strength is easy central management.
In a peer-to-peer network:
P2P has no central server — each peer can both request and provide resources, which is robust but harder to secure.
Thin vs thick clients 胖客户端
- A thin client 瘦客户端 does little processing locally and relies on a powerful server (web terminals, remote desktops).
- A thick client has strong local processing and storage and runs full applications itself (a normal desktop PC).
- Thin → high server load, high network reliance; thick → the opposite.
A thin client:
A thin client offloads most work to the server (high network reliance); a thick client does its own processing and storage.
Wired vs wireless, and the cloud
- Wired (Ethernet over twisted-pair or fibre): faster, lower latency, more secure.
- Wireless (Wi-Fi, Bluetooth, cellular): convenient and mobile, but slower and prone to interference and eavesdropping.
- Cloud computing 云计算 delivers servers/storage/software over the internet, hosted by a third party: scalable and accessible anywhere, but needs internet and hands your data to a third party.
- Also know: a Uniform Resource Locator (URL) names a web resource and the Domain Name Service (DNS) turns it into an IP; a static IP address is fixed while a dynamic IP address is given out by DHCP, and a public IP address is internet-routable; wide-area links may use the PSTN; a wireless device has a WNIC.
Compared with wireless, a wired connection is generally:
Wired wins on speed, latency, reliability and security; wireless wins on convenience and mobility.
You've got it
- networks share resources/data, allow central management and communication
- LAN = small, owned, fast; WAN = large, telecom, slower (internet = biggest WAN)
- client-server = central server (single point of failure); P2P = equal peers, no server
- thin client relies on the server; thick does its own work · wired faster, wireless convenient · cloud = services over the internet