LAN,WAN Flashcards
LAN vs WAN
- LAN-small geographical area; uses private infrastructure
* WAN-large geographical area; uses public infrastructure
Features of a WAN
- Wide area network
- Large geographical area
- Uses public infrastructure(e.g. phone lines, satellites)
Purpose and function of hub
- Piece of hardware
- Device connect to it using cable(or wirelessly if wireless access point is used)
*Receives signals from devices and forwards them onto
their destination
*Transmits the signal to all devices attached to it
Purpose and function of a router
*Hardware which connects devices in a network(using
cables or wirelessly)
*Receives signals from devices and forwards them to
their destination
- Remember addresses of devices attached to it
- Often has integrated modem for internet access
Drawbacks of a client-server network
- Expensive server required
- May need to hire a technician to run the network
- If the server goes down, no client can be used
Features of a LAN
- Local area network
- small geographical area
- uses private infrastructure
Benefits of a peer-to-peer network
*can store document software,etc.
*Computers are independent and can be removed from
the network and still used
Purpose and function of an NIC (network hardware)
- Network interface care
- Hardware device
- Within a computer(cam be added to a computer)
*Allows Ethernet cables be connected for access to a
network
Description of a client-server network
*The network has one powerful computer, the server.
This stores all data,conducts all process,etc
*The remaining computers are clients. They store their
data on the server, access data from the server, etc.
Purpose and function of a modem
- Modulator-demodulator
- Allows connection to the Internet
*Converts analogue phone line data to digital computer
data and back again
Factors that affect network performance
- Bandwidth(how much data the network can transmit at
a time)
*Amount of traffic(how much data is being transferred
across it)
*Hardware being used(including type of cable)
Purpose and function of Ethernet cable
*Copper cable connected between devices, e.g.
computer and router
- Transfers data in a network
- Transmits electrical signals
- connects devices physically in a network
Benefits of a client-server network
*Central file storage (and any client and access same
data
- Users can logon to any client and access same data
- Central security management
- Central control
- Central monitoring
Drawbacks of a server-client network
- Expensive server required
- May need to hire a technician to run the network
- If the server goes down, no clients can be used
Purpose of a wireless access point
- Hardware device
- Connected to a device,e.g.router/switch
*Allows a WNIC (wireless network interface card) to
connect to the device via Wi-Fi
Purpose and function of fibre-optic cable
- Cable that transmits light signals
* Faster transmission than copper cables
Purpose and function of a switch
*Hardware which connects devices in a network using
cables (or wirelessly if a WAP is used)
*Receives signals from devices and forwards them to
their destination
*Does not remember addresses of devices attached;
checks each device to find the one to send the signal t
to
Purpose and function of a router
*Hardware which connects devices in a network (using
cables or wirelessly)
*Receives signals from devices and forwards them to
their destination
- Remembers addresses of devices attached to it
- Often has integrated modem for internet access
Examples of network hardware devices
- Router +Modem (often combined)
- Switch/Hub
*NIC (network interface controller)
WNIC (wireless NIC)
- Copper/Ethernet cables
- Fibre-optic cables
- wireless access point
Description of the Internet
*Worldwide network made up of smaller networks (e.g.
WAN, LAN)
*The infrastructure that connects computers, e.g.
telephone lines
Drawbacks of the virtual network
*Security of the network can be compromised by
intercepting transmission of hackers
- Need to encrypt data
- Need someone to manage it
Drawbacks of a peer-to-peer network
*No central security, if one computer gets a
virus, it can be passed to others
*No central management
*Every user is responsible for their own
backup
Description of ‘the cloud’
Software, services and data that are run/stored on the Internet
Benefits of the virtual network
*Employee can access files, data, software, etc. from
anywhere with Internet access
*Employees can work elsewhere, e.g. at home with
clients
Benefits of cloud storage
*Files/data can be accessed anywhere with Internet
access
- Easily increases storage size
- Backup and security managed externally
Device that hosts a website
Web Server
Drawbacks of cloud storage
- Cannot access data without Internet access
* No control over security or backup
Purpose of URL
- Uniform resource locator
- User-friendly, memorable name for a website
- Easier to remember/use than an IP
Purpose and function of WNIC (network hardware)
- Wireless network interface card
- Device that connects to or is put into a computer
- Transmits and receives Wi-Fi signals
Benefits and drawbacks of fibre-optic cable
+High bandwidth
+small and light
+little interference
- Expensive to buy, set up and maintain
- Difficult to install: can be easily damaged
Purpose of IP
*Internet Protocol
*Numerical address of a piece of hardware connected to
the internet
Function of DNS
- Domain name server
- Browser sends URL to DNS
- DNS has database of domains and matching server IPs
- DNS finds domain in database*
- DNS returns server IP to browser
*If DNS does not find IP, it forwards request to higher
DNS. Higher DNS then returns IP to original DNS
Purpose and function of Hub
- Piece of hardware
- Devices connect to it using cables (or wirelessly if wireless access point is used)
*Receives signals from devices and forwards them onto
their destination
*Transmits the signal to all devices attached to it
Description of WWW
- World Wide Web
* The websites and resources hosted on the Internet
