1.3.1 - Networks and Topologies Flashcards
What is a Network?
Two or more computers that are connected together for the purpose of communicating data
What are the advantages of networking?
- Users can
share files and can access their files from any computeron the network - Users can
share peripherals; printersand connections to other networks - Severs can
control security, software updates and backupof data -
Communicationwith other people
What is LAN?
- Local Area Network
- Covers a small area on a single site
- All hardware for a LAN is owned by the user
- Wired with UTP cables, fibre optic or wireless using wifi
What is a WAN?
- Wide area network
- Covers a large area, connecting LANs together
- Infrastructure between the LANs is leased from telecommunication companies who own/manage it
- Connected by telephone lines, fibre optic cables or satellites
What are the disadvantages of networking?
- Increased security risk to data
- Malware and viruses spread easier between computers
- If a server fails, computers connected may not work
- Computers may run slower if a lot of data is travelling the network
- Expensive
What is a WAP?
Wireless Access Point
- Networking hardware that allows a Wi-Fi device to connect to a wired network
What is an NIC?
Network Interface Controller/Card
- A hardware component that connects a computer to a computer network
What is a client server model?
A Server:
- Controls access and security to one shared file store
- Manages internet access and printing jobs
- Provides email services
- Runs data backups
- A client makes requests to the server for data and connections
Define “client”
A device that makes requests to a server for data and connections
What are the advantages of a client-server model?
- Easier to manage files, take backups of all shared data & install software updates to all computers
What are the disadvantages of a client-server model?
- Can be
expensiveto set up/maintain - Requires IT specialists to maintain
- The
server is a single point of failure - Users lose access if server fails
What is a peer to peer model?
- A peer is a computer on a network and is equal to all other peers
Peers: - Send their own files to each other
- Responsible for its own security/backups
- Usually have their own printers
- Can send print jobs to other peers to process, however they must be turned on
What are the advantages of a peer to peer model?
- Easy to maintain
- Specialist staff aren’t required
- No dependency on a single computer
- Cheaper
- No expensive hardware needed
What are the disadvantages of a peer to peer model?
- Less secure network
- Users need to manage their own backups
- Difficult to maintain a well ordered file store
What is bandwidth?
- The amount of data that can be sent and received successfully in a given time
- Not a measure of how fast data travels, but how much data can be sent
- Measured in bits per second, often called bit rate
How can the number of users affect the performance of a network?
- Too many users/devices can cause the network to slow down if there is insufficient bandwidth
What is Transmission Media?
The physical media over which data is transmitted
How does transmission media affect the network performance?
(physical)
- Wired connections have a higher bandwidth than wireless
- Fibre optic cables have a higher bandwidth than copper cables
How can the error rate affect the network?
- Less reliable connections increase the number of errors that occur when data is transferred, meaning it has to be resent until it arrives
- The quality of the connections depends on the range of devices & other environmental factors
How can latency affect a network?
- Latency is the delay from transmitting data to receiving it, caused by bottlenecks in the infrastructure
eg. not using switches to appropriately segment traffic
What is the internet?
A global collection of interconnected networks
What is a Domain Name Service?
- Converts web addresses to IP addresses for a router
- Process is carried out by the service, which is made up of multiple Domain Name Servers
What is a DNS?
- Domain Name Server
- Matches the URL of a website into an IP address of a web server
What is hosting?
Stored websites in servers for a dedicated purpose (DNS converting)
What is the cloud storage?
Servers that store data and programs remotely that can be accessed and used over the internet
Provide access to anything, anywhere, an auto backup and collab of documents
What is a Router?
A device for connecting devices on a wide area network
What are Web Servers & Clients?
- Web Servers provide services (eg Server -> Web Pages, File server -> File storage)
- Clients request/use services from a server
What are the advantages & disadvantages of a Star Network Topology?
A:
- The switch makes sure traffic only goes where it is intended
- If a single cable breaks only that computer is affected
D:
- The switch is a serious point of failure
What are the advantages & disadvantages of a Mesh Network Topology?
A:
- If you break any connections the traffic can be rerouted
D:
- Lots more cabling & switch hardware required - adds to cost
What is a Partial Mesh Topology?
- Where multiple routes exist between different devices but not every device is connected to every other device
- Compromise that lowers hardware needed for a full mesh topology
What is a Mesh Topology?
Nodes connected so there is more than one route to the destination
What is a Star Topology?
A network where each node is connected to a central router or switch
What is a Switch?
Uses the MAC address to route traffic (frames) to the correct connected device
Connects devices on a local area network
