01 Section 2 - Network types and topologies Flashcards
What is a client-server network?
- networks made up of clients and a server
- it is managed by a server
- devices connected to the server are called clients
How are files and software stored on a client server network?
-stored centrally on the server rather than on individual client devices
What is the client-server relationship?
- Clients send requests to the server
- the server processes the request and responds
What does the server stores on a client-server network?
-user profiles
-passwords
-access information
IT MAY REQUEST A PASSWORD FOR CERTAIN REQUESTS OR DENY REQUESTS TO USERS WITHOUT THE RIGHT ACCESS LEVEL
What is an example of where a client-sever network is used?
- most of the Internet work on a client-server relationship
e. g. websites are hosted on web servers, web browsers are client programs which send requests to the web severs
What are the pros of client-server networks?
- easier to keep track of files as they are stored centrally
- can perform centralised backups
- can perform centralised installation and updates of software
- easier to manage network security (anti-malware software and user access levels)
- servers are very reliable and are always on
What are the cons of client-server networks?
- expensive to set up and needs IT specialists to maintain the network and server
- server dependence, if the server goes down all clients loose access to their work
- servers may become overloaded if too many clients are accessing it at once
What are peer-to-peer networks?
Devices are all equal, they connect directly to each other without a server
Where are files stored on a peer-to-peer network?
-files are stored on individual devices and share them with others
What is an example of where a peer-to-peer network is used?
-at home to share files between devices, or connect devices to a printer
What are the pros of peer-to-peer networking?
- easy to maintain, don’t need expertise or expensive hardware
- no dependence on a server, if one device fails the whole network isn’t lost
What are the cons of peer-to-peer networking?
- no centralised management (devices need updates and security installed individually)
- copying files between devices creates duplicate files (lose track of what is stored where and what files are up-to-date)
- peer machines are less reliable (data can be lost if one fails)
- machines are prone to slow down if another is accessing it
What are examples of peer-to-peer applications on the Internet?
- video calling (e.g. Skype)
- file sharing
What is a topology?
The layout of a network
What are the different types of network topologies you can have?
- star topology
- bus topology
- ring topology
- mesh topology
What is a star topology?
A topology where all devices are connected centrally to a central switch or server that controls the network.
- central switch allows many devices to access the server simultaneously
- can be wired or wireless
What are the pros of a star topology network?
- if a device fails or a cable is disconnected, the rest of the network is unaffected
- simple to add more devices to the network
- better performance than other setups (all devices can transmit data at once(unlike ring), very few data collisions(unlike bus))
What are the cons of a star topology network?
- in a wired network every device needs a cable to connect centrally - this can be expensive
- if there is a problem with the switch or server the whole network is affected
What is a bus topology?
When all devices are arranged in a line, connected to a single backbone cable
-devices send data in both directions, this causes data collisions which slows down the network
What is a ring topology?
When data moves in one direction around the ring, preventing collisions
- only one device can send data at a time
- data passes through many devices before reaching its destination
What is a mesh topology?
It is a decentralised network design, networking devices are either directly on indirectly connected to every other one (no need for one central switch or server)
How do mesh networks work?
By sending data along the fastest route from one device to another
What is the advantage of a mesh topology?
-no single point where a network can fail (if one device fails then the data is sent along a different route to get to its target)
What is the disadvantages of mesh topology?
-expensive because you need a lot of wires to connect many devices together (now people are using more wireless technology, so it’s more of a practical option)
What is a full mesh topology?
A network where every device is connected to every other device
What is a partial mesh topology?
A network where not every device is directly connected to every other
