1.3 - Computer Networks, Connections and Protocols Flashcards
What is a Wide Area Network (WAN)?
A network (over a relatively large geographical area) in which the computers communicate using resources supplied by a third party carrier.
What is a Local Area Network (LAN)?
A self-contained network over a relatively small geographical area.
What are the characteristics of a WAN?
Large geographical area; collection of LAN’s; infrastructure between LAN’s leased from telecommunication companies; fibre optics, telephone lines, satellite links used for connection
What are the characteristics of a LAN?
Single site; small geographical area; organisation owns all hardware; fibre-optics, UTP, wireless connection
What affects the performance of a network?
Bandwidth, Latency, Error rate
What is meant by bandwidth?
The amount of data that can be sent and received successfully per second
What is latency?
The length of time a packet of information takes to travel through the network
What is the role of a Network Interface Card (NIC)?
To connect a device to a network.
What is the role of a Wireless Access Point (WAP)?
To allow devices to wirelessly connect to a network.
What is the role of a router?
To route data packets between a LAN and the Internet.
To connect networks, using IP addresses.
To store the IP addresses of the connected networks.
What is the role of a switch?
To connect each node in a network and send data between computers on a LAN.
To use MAC addresses to connect nodes.
To look for the correct MAC addresses as they are being accessed.
What is the Internet?
A collection of inter-connected networks.
What is the Domain Name Service made up of?
Domain Name Servers
What is the role of the DNS in converting a URL into an IP address?
A DNS server translates a web address into an IP address.
When a DNS server receives a request not in its database, the request is passed on to another server until it reaches one with the matching name and IP address.
What is a server?
A powerful computer which provides services or resources required by any clients.
What is a client?
A computer or device that requests services or resources provided by the server.
Types of servers?
File server, print server, email server, web server, database server
What is web hosting?
A service offered by companies in which the facilities need to create and maintain web pages and files for websites are provided.